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CILRT is an important work in the overhaul of nuclear power plants. VOCs from paints and cleaners used in the containment during the overhaul will migrate inside the containment, and the numerous rooms and compartments inside the containment make the air flow impeded, and the VOCs may be enriched to bring combustion risk. The complete fire risk analysis method includes volatilization kinetics of chemicals, mixture explosion limits, and numerical simulation of VOCs diffusion and migration. The volatilization rate at the lowest room temperature of 20°C is used as a conservative input, the complement of CAITA realistic model is used as the flow domain, and the geometry is appropriately simplified, and the steady ventilation process, the internal flow and the laws of diffusion and agglomeration of 12 kinds of VOCs gases in the 9-h pressure-holding process are investigated by Computational Fluid Dynamics. The simulation results of steady ventilation show that the VOCs gases are almost uniformly carried by the air to all spaces inside the containment, and the explosion risk is low. The concentration field of the steady ventilation process was taken as the initial boundary condition and unsteady state simulation of the 9-h holding pressure process was performed. The results show that the gas flow inside the containment basically stops after 3456 s of pressure holding. With the extension of time, the VOCs gases accumulate at the bottoms of the three lower layers of the containment under the effect of laminar diffusion and gravitational settling, where the total concentration of the mixed gases reaches the highest at the bottom of the lowest layer. The total concentration of the VOCs gas mixture was below the lower explosion limit throughout the 9-h pressure-holding process, and the explosion risk was low.

How can we make the building information model accessible to all stakeholders on a project? An efficient approach is to access the building information model is to use the software that created the model. However, not all stakeholders will be able to use this highly specialized software—due to lack of training and expensive licences—even if some software specially developed a simplified version of the viewer to browse the model, however, it still failed to provide convenient access to these models for participants from a wide range of backgrounds. The current development of BIM model visualization and interactive applications is mainly based on two technologies: WebGL and game engines. What is the general workflow of WebGL and Game Engines supporting application development? What are their characteristics respectively? What conditions are restricted? There are no relevant academic papers to discuss and compare these two types of platforms. Therefore, this is the content of this essay. By comparing the workflow and characteristics of BIM visualization and interactive application development based on WebGL and Game Engine, it can provide a reference for heritage building managers when planning the development of relevant application tools and meet the participation needs of different stakeholders.

The nearby radio galaxy M87 is a very high-energy (VHE) gamma-ray emitter established by observations with ground-based gamma-ray detectors. Here we report the long-term monitoring of M87 from 2021 to 2024 with the Large High Altitude Air Shower Observatory (LHAASO). M87 has been detected by LHAASO with a statistical significance ∼ 9 σ . The observed energy spectrum extends to 20 TeV, with a possible hardening at ∼20 TeV and then a clear softening at higher energies. Assuming that the intrinsic spectrum is described by a single power law up to 20 TeV, a tight upper bound on the extragalactic background light intensity is obtained. A strong VHE flare lasting 8 days, with a rise time of ${\tau }_{r}^{\mathrm{rise}}=1.05\pm 0.49$ days and decay time of ${\tau }_{d}^{\mathrm{decay}}=2.17\pm 0.58$ days, was found in early 2022. A possible GeV flare is seen also in Fermi Large Area Telescope data during the VHE flare period. The variability time as short as 1 day seen in the LHAASO data suggests a compact emission region with a size of ∼3 × 10 ^15 δ cm ( δ being the Doppler factor of the emitting region), corresponding to a few Schwarzschild radii of the central supermassive black hole in M87. The continuous monitoring of the source reveals a duty cycle of ∼1% for VHE flares with a flux above 10 ^−11 erg cm ^−2 s ^−1 .

The first source catalog of the Large High Altitude Air Shower Observatory (LHAASO) reported the detection of a very high energy gamma-ray source, 1LHAASO J1219+2915. This Letter presents a further detailed study of the spectral and temporal behavior of this pointlike source. The best-fit position of the TeV source (R.A. = 185.°05 ± 0.°04, decl. = 29.°25 ± 0.°03) is compatible with NGC 4278 within ∼0.°03. Variation analysis shows an indication of variability on a timescale of a few months in the TeV band, which is consistent with low-frequency observations. Based on these observations, we report the detection of TeV γ -ray emissions from this low-luminosity active galactic nucleus. The observation by LHAASO's Water Cherenkov Detector Array during the active period has a significance level of 8.8 σ with a best-fit photon spectral index Γ = 2.56 ± 0.14 and a flux f _1–10 TeV = (7.0 ± 1.1 _sta ± 0.35 _syst ) × 10 ^−13 photons cm ^−2 s ^−1 , or approximately 5% of the Crab Nebula. The discovery of VHE gamma-ray emission from NGC 4278 indicates that compact, weak radio jets can efficiently accelerate particles and emit TeV photons.

Abstract By precisely writing down the matrix element of the local Boltzmann operator ( $${\mathrm{e}}^{-\tau h}$$ e - τ h , where $$h$$ h is the Hermitian conjugate pairs of off-diagonal operators), we have proposed a new path integral formulation for quantum field theory and developed a corresponding Monte Carlo algorithm. With the current formula, the Hubbard–Stratonovich transformation is not necessary, accordingly the determinant calculation is not needed, which can improve the computational efficiency. The results show that, the simulation time has the square-law scaling with system sizes, which is comparable with the usual first-principles calculations. The current formula also improves the accuracy of the Suzuki–Trotter decomposition. As an example, we have studied the one-dimensional half-filled Hubbard model at finite temperature. The obtained results are in excellent agreement with the known solutions. The new formula and Monte Carlo algorithm could be applied to various studies in future.

Abstract Background Nomograms are rarely employed to estimate the survival of patients with advanced and metastatic pancreatic cancer (PC). Herein, we developed a comprehensive approach to using a nomogram to predict survival probability in patients with advanced and metastatic PC. Methods: A total of 323 patients with advanced and metastatic PC were identified from the Chinese People’s Liberation Army (PLA) General Hospital. A baseline nomogram was constructed using baseline variables of 323 patients. Additionally, 233 patients, whose tumors showed initial responses to first-line chemotherapy, were enrolled in the chemotherapy response-based model. 128 patients and 108 patients with advanced and metastatic PC from January 2019 to April 2021 were selected for external validating baseline model and chemotherapy response-based model. The 1-year and 2-year survival probability was evaluated using multivariate COX regression models. The discrimination and calibration capacity of the nomograms were assessed using C-statistic and calibration plots. The predictive accuracy and net benefit of the nomograms were evaluated using ROC curve and DCA, respectively. Results In the baseline model, six variables (gender, KPS, baseline TB, baseline N, baseline WBC and baseline CA19–9) were used in the final model. In the chemotherapy response-based model, nine variables (KPS, gender, ascites, baseline N, baseline CA 19–9, baseline CEA, change in CA 19–9 level at week, change in CEA level at week and initial response to chemotherapy) were included in the final model. The C-statistics of the baseline nomogram and the chemotherapy response-based nomogram were 0.67 (95% CI, 0.62–0.71) and 0.74 (95% CI, 0.69–0.77), respectively. Conclusion These nomograms were constructed to predict the survival probability of patients of advanced and metastatic PC. The baseline model and chemotherapy response-based model performed well in survival prediction.

Abstract Background γδT cells play an important role in the mucosa inflammation and immunity-associated disorders. Our previous study reported that γδ T cells producing IL-17 were involved in the pathogenesis of post-infectious irritable bowel syndrome (PI-IBS). However, their subset characteristic profile in this kind of disease remains unclear. Thus the current study’s aim is to investigate the functionally predominant subset and its role in PI-IBS. Methods The total T cells were collected from the peripheral blood of patients with PI-IBS. The peripheral proportion of Vδ1 and Vδ2 subset was detected by FACS after stained with anti δ1-PE and anti δ2-APC. The local colonic proportion of this two subsets were measured under laser confocal fluorescence microscope. Vδ1 γδ T cells were enriched from the total peripheral T cells by minoantibody-immuno-microbeads (MACS) method and cultured, functionally evaluated by CCK-8 assay (proliferation), CD69/CD62L molecules expression assay (activation) and ELISA (IL-17 production) respectively. Results 1. Vδ1 γδ T cells significantly increased while Vδ2 γδ T cells remained unchanged in both the peripheral blood and local colonic tissue from PI-IBS patients (p

Ocean acoustics is an important research topic in ocean engineering. Among them, the location of the impact point at sea is an important method to evaluate the firing accuracy of naval guns. Most of the traditional methods for locating the impact point at sea use the optical positioning principle, which is expensive and has a high false alarm rate. It is easy to be affected by natural conditions, such as marine visibility. Based on this, this paper proposes an improved location method of the impact point at sea based on the Beidou differential and acoustic array, which improves positioning accuracy greatly. First, through the simulation analysis of single array positioning error, this paper gives the basis of the positioning method, then deduces the positioning principle of this method in detail, and simulates and analyzes the positioning error of the double array. Finally, the simulation experiment of the voice signal is carried out to verify the positioning performance of the dual cross-array. The results show that the direction finding of the dual cross-array is very accurate, and the ranging error is relatively large. Among the five positioning points selected in this paper, the maximum relative direction-finding error is 0.33%, and the maximum relative ranging error is only about 1%, which is much better than the ranging performance of a single array. It has certain engineering application values and provides a certain reference for the design of the impact point positioning scheme at sea.

Abstract Strong anisotropic compression with pressure on the remarkable non-linear optical material KBe2BO3F2 has been observed with the linear compression coefficient along the c axis found to be about 40 times larger than that along the a axis. An unusual non-monotonic pressure response was observed for the a lattice parameter. The derived bulk modulus of 31 ± 1 GPa indicates that KBe2BO3F2 is a very soft oxide material yet with stable structure up to 45 GPa. A combination of high-pressure synchrotron powder X-ray diffraction, high-pressure Raman spectroscopy, and Density Functional Theory calculations points to the mechanism for the unusual pressure response being due to the competition between the K-F bond length and K-F-K bond angle and the coupling between the stretching and twisting vibration modes.

The intrinsic nature of glass states or glass transitions has been a mystery for a long time. Recent studies have suggested that glass-formation versus crystallization occurs for potential energy landscapes (PEL) having a specific structure and the present work is an elaboration of this perspective. To explore how the flatness of the PEL related to glass transition, we develop a method to adjust the PEL in a controllable manner. We demonstrate that a relatively flat PEL is not only necessary but also sufficient for the formation of a nanoscale glass. We show that: (1) as long as a nanocluster is located in a region of PEL with local minimum deep enough, it can undergo an abrupt thermodynamic transition reminiscent of the first order transition of bulk materials; and (2) if a nanocluster is located in a relatively flat PEL, it can undergo a very broad transition in their dynamics and thermodynamics that resembles glass-formation in bulk materials in many ways. All these transitions are independent of its structure symmetry, order or disorder. Our simulations also uncover the direct transition from one potential energy minimum to another below the glass transition temperature, which is the consequence of flat PELs.

The Taklimakan Desert in the Tarim Basin is the largest desert in Central Asia, and is regarded as one of the main dust sources to the Northern Hemisphere. Late Cenozoic sedimentary sequences with intercalated in-situ aeolian dune sands in this area preserve direct evidence for the Asian desertification. Herein, we report a high-resolution multi-proxy climatic record from the precise magnetostratigraphic dated Hongbaishan section in the central Taklimakan Desert. Our results show that a fundamental climate change, characterised by significant cooling, enhanced aridity, and intensified atmospheric circulation, occurred at 2.8 Ma. Good correlations between paleo-environmental records in the dust sources and downwind areas suggest a broadly consistent climate evolution of northwestern China during the late Cenozoic, which is probably driven by the uplift of the Tibet Plateau and the Northern Hemisphere glaciation.

Prediction of fatigue life is a critical issue in the design of aerostructures.Stress concentrations are crucial in this connection. The paper proposes adesign optimisation methodology aimed at achieving a longer and saferworking record for a structure over its lifecycle, based on the redistributionof material to balance the effect of stress concentrations.The idea ofdesign optimisation in situations where primary failure is driven by stressconcentrations is worthwhile and has the potential to offer designengineers a better view in the design structures subjected to fatigueloading and an opportunity for better utilisation of material with itsassociated economic benefits.Prediction of fatigue life is a critical issue in the design of aerostructures.Stress concentrations are crucial in this connection. The paper proposes adesign optimisation methodology aimed at achieving a longer and saferworking record for a structure over its lifecycle, based on the redistributionof material to balance the effect of stress concentrations.The idea ofdesign optimisation in situations where primary failure is driven by stressconcentrations is worthwhile and has the potential to offer designengineers a better view in the design structures subjected to fatigueloading and an opportunity for better utilisation of material with itsassociated economic benefits.

Although both theoretical predictions and experimental observations have demonstrated that the Gilbert damping is anisotropic at ferromagnet/semiconductor interface possessing robust interfacial spin–orbit coupling, it is not well understood whether non-local Gilbert damping driven by spin pumping in heavy metal/ferromagnetic metallic bilayers is anisotropic or not. Here, we investigated the angular and frequency dependence of magnetic relaxation in epitaxial Pd/Fe films on MgO(001) substrates. After disentangling parasitic contributions, we unambiguously observe that the non-local Gilbert damping is isotropic in the Fe(001) plane, suggesting that the spin transport across the Pd/Fe interface is independent of the Fe magnetization orientation. First principles calculations reveal that the effective spin mixing conductance of the Pd/Fe interface is nearly invariant for different magnetization directions, in good agreement with the experimental observations. These results offer valuable insight into spin transport in metallic bilayers, and facilitate the development of next-generation spintronic devices.

Male Hartley guinea pigs were fed semipurified diets containing various levels of psyllium and cholesterol to determine mechanisms by which psyllium lowers plasma low density lipoprotein (LDL) concentrations. Four diets were tested: control diets with 12.5% (w/w) cellulose, and psyllium diets in which cellulose was partially replaced with 7.5% (w/w) psyllium. Two levels of dietary cholesterol were used, either low (LC, 0.04%, w/w) or high (HC, 0.25%, w/w). Plasma LDL was reduced by 30 and 54% with psyllium intake in the LC and HC groups, respectively (P < 0.001), while plasma very low density lipoprotein (VLDL) was lowered only in the HC group (P < 0.001). Psyllium intake modified LDL composition and size compared to LDL from control animals with a lower proportion of cholesteryl ester and higher proportion of triacylglycerol, lower molecular weight, smaller diameter, and higher peak density (P < 0.001). Plasma VLDL from animals fed the psyllium-HC diet compared to the control-HC contained lower relative proportions of free and esterified cholesterol and a higher proportion of triacylglycerol, compositional characteristics similar to VLDL from animals fed LC diets. Hepatic free and esterified cholesterol concentrations were significantly reduced by psyllium an average of 25 and 55%, respectively, while hepatic HMG-CoA reductase activity was increased in both psyllium groups compared to the respective controls (P < 0.001). In addition, psyllium intake reduced hepatic acyl-CoA:cholesterol acyltransferase (ACAT) activity in both the LC and HC groups (P < 0.001) and increased hepatic membrane apoB/E receptor number (Bmax) by 17 and 52% for animals fed LC and HC diets, respectively (P < 0.005). Significant psyllium-induced increases in cholesterol 7 alpha-hydroxylase of 4- and 1.6-fold were also observed in animals fed the LC and HC diets respectively (P < 0.001). These results indicate that psyllium generates a negative cholesterol balance across the liver which results in induction of cholesterol 7 alpha-hydroxylase and HMG-CoA reductase and suppression of ACAT activities, upregulation of apoB/E receptors, and secretion of smaller VLDL particles, metabolic alterations that contribute to a lowering of plasma LDL cholesterol levels.

High spin states in 108Ag have been studied via in-beam γ spectroscopy techniques using the 104Ru(7Li, 3n) reaction. The previously known level scheme has been extended, and a new band structure has been established. The configurations have been tentatively assigned to all observed rotational bands. The signature splitting behavior of the p g9/2 ⊗ νg7/2 band has been discussed and interpreted as a change in shape from near-oblate to prolate. A systematic study of the nearly degenerate negative-parity bands in the A ~ 110 mass region has been performed and it is found that the yrast band in 108Ag and its side band show different behaviors with those expected from a pair of chiral bands. [ABSTRACT FROM AUTHOR]