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Background: Tumor budding (TB) is a negative prognostic factor in colorectal cancer; however, its prognostic impact following neoadjuvant therapy for patients with rectal cancer remains unclear. This study aims to assess the prognostic impact of TB and the correlation between TB and other pathological features in patients with rectal cancer after neoadjuvant therapy. Methods: A comprehensive search of PubMed, Embase, Cochrane, Scopus, CNKI, Wanfang, and ClinicalKey databases was conducted for studies on the prognosis of TB in rectal cancer after neoadjuvant therapy from the inception of the databases to January 2023, and the final literature included was determined using predefined criteria. Quality assessment of the studies included, extraction of general and prognostic information from them, and meta-analyses were carried out progressively. Results: A total of 11 studies were included, and the results of the meta-analysis showed that high-grade tumor budding (TB-1) increased the risk of poor 5-year disease-free survival (HR = 1.75, 95% CI 1.38–2.22, P < 0.00001), 5-year overall survival (HR = 1.77, 95% CI 1.21–2.59, P = 0.003), local recurrence (OR = 4.15, 95% CI 1.47–11.75, P = 0.007), and distant metastasis (OR = 5.36, 95% CI 2.51–11.44, P < 0.0001) in patients with rectal cancer after neoadjuvant therapy. TB-1 was significantly associated with poor differentiation and lymphatic, perineural, and venous invasion. Conclusion: Tumor budding is significantly correlated with unfavorable prognosis and poor pathological characteristics following neoadjuvant therapy for rectal cancer. We anticipate more high-quality, prospective studies in the future to confirm our findings. Systematic review registration: PROSPERO CRD42022377564. [ABSTRACT FROM AUTHOR]

Objective: At present, pancreatic cancer (PC) has a high morbidity and mortality rate and a poor prognosis. The aim of this article was to study the efficacy and safety of apatinib combined with radiotherapy in the treatment of advanced PC. Methods: The PubMed, Cochrane Library, Embase, Wanfang, CNKI, VIP, and CBM databases were searched by computer to identify studies on the application of apatinib in patients with advanced PC. The patients in the included study were divided into an observation group (apatinib combined with radiotherapy) and a control group (radiotherapy only), and meta-analysis was performed for each outcome with Revman 5.4 software. This study was successfully registered on the PROSPERO website, and the registration number is CRD: 42,022,384,056 (available at https://www.crd.york.ac.uk/PROSPERO/display%5frecord.php?RecordID=384056). Results: A total of 7 randomized controlled trials (RCTs) with 428 patients were included, including 215 in the observation group and 213 in the control group. Compared with the control group, the observation group showed a greater objective response rate [OR = 3.26, 95% CI (2.18, 4.87), P < 0.0001], disease control rate [OR = 5.04, 95% CI (3.12, 8.12), P < 0.0001], complete response rate [OR = 3.87, 95% CI (1.51, 9.88), P = 0.005], and partial response rate [OR = 2.43, 95% CI (1.63, 3.61), P < 0.001], The 1-year survival rate [OR = 2.39, 95% CI (1.15, 4.96), P < 0.05], 2-year survival rate [OR = 2.41, 95% CI (1.03, 5.61), P < 0.05], progression-free survival time [MD = 1.17, 95% CI (0.37, 1.96), P < 0.05], overall survival time [MD = 1.47, 95% CI (0.13, 2.80), P < 0.05], while the stability rate [OR = 1.14, 95% CI (0.72, 1.81), P = 0.58] and various complications were not significantly different between the two groups. Conclusion: Apatinib combined with radiotherapy was more effective than radiotherapy alone in the treatment of advanced pancreatic cancer (PC), and apatinib had acceptable safety. However, since our study was limited by the quantity and quality of the included studies, we look forward to more large-sample, multicentre, and high-quality RCTs in the future to verify the conclusions. [ABSTRACT FROM AUTHOR]

• The locations of flash point and scaling via drift flux model were studied. • Variation of calcite scaling amount with wellbore depth was investigated. • The factors affecting the amount of calcite scaling were discussed. • The mechanism of geothermal fluid flash was analyzed. Geothermal energy, as a renewable energy source, has been intensively developed recently because its utilization can reduce CO 2 emission, climate warming and sea level rising, and be beneficial to promote sustainable development. However, scaling in the wellbores often happens during the rising of geothermal fluids. At present, the methods to explore the scaling location principally focus on real measurement techniques and numerical simulation method. In comparison with the former, the latter is extremely time- and labor-saving to predict the scaling location based on the coupling model. In this study, the flash point and scaling locations of two geothermal wells in Hebei province are numerically simulated via ECO2N equation of state module in TOUGHREACT software, and the factors affecting the flash point and scaling locations of geothermal wells are explored. At the same time, the mechanism of geothermal fluid flash is analyzed. The prediction results show that the relative errors of scaling locations in geothermal well I and II are 5.43 % and 6.82 % compared to the field measured data; the pressure and temperature of geothermal fluids at well bottom can be calculated based on the related parameters of wellhead fluid; the locations of flash point and scaling can be determined according to the sudden increases of CO 2 partial pressure and scaling amount, respectively. Furthermore, the liquid mass flow rate, CO 2 mass flow rate and wellbore diameter have prominent influence on the locations of flash point and scaling, while wellbore diameter have significant effect on the amount of calcite scaling. The above conclusions provide useful guidelines for the next scaling removal and control in the production wellbore during the utilization of the geothermal energy. [Display omitted] [ABSTRACT FROM AUTHOR]

Most existing image dehazing methods rely on the solution of the atmospheric scattering model or supervised learning based on paired images. However, owing to incomplete prior knowledge and the lack of paired hazy and haze‐free images of the same scenes as training samples, their performances for single image dehazing are unsatisfactory. Here, the authors present an unpaired image learning method based on the attention mechanism for single image dehazing problems. The method uses the constraint transfer learning ability and circulatory structure of CycleGAN to carry out an unsupervised image dehazing task for unpaired data. Considering the complexity of the haze distribution in actual imaging and human visual characteristics, the improved channel attention and domain attention mechanisms are integrated into the network to process different features and different regions non‐uniformly. The experimental results show that the proposed method achieves good results on both synthetic datasets and real hazy images. [ABSTRACT FROM AUTHOR]

In a fluidized bed evaporator, heat transfer between walls of heated tubes and solutions belongs to a vapor-liquid-solid flow boiling, and solid particles are fluidized by a vapor-liquid flow. In this evaporator, evaporation can operate continuously without fouling on tube walls even for the solutions of high viscosity and density, like extract liquids of traditional Chinese medicines. In this article, a fluidized bed evaporator with an external natural circulating vapor-liquid-solid flow boiling at industrial scale with heat transfer area of 18.9 m2 has been developed based on the previous experimental investigations in a laboratory evaporator and a pilot installation and applied in the evaporating concentration of extract liquids of traditional Chinese medicines first time. Its evaporation capacity changes from 1,100 to 1,400 kg/h. The relative density of extract solutions changes from 0.94 to 1.35, and viscosity from 1.69 to 20.68 Pa·s. Online zero-fouling and stable operations have been proved. Under similar conditions, overall heat transfer coefficient and evaporation intensity of industrial fluidized bed evaporators are higher than those of traditional vapor-liquid evaporators, but they decrease slightly compared to those of pilot one, and the reduced ratio is about 20%. Other examples of industrial applications are also introduced. [ABSTRACT FROM AUTHOR]

• A three-dimensional EMI model for the embedded piezoelectric sensor is developed. • The hardening process of concrete is measured by the PS-EMI and CPS-EMI thchnique. • The contradiction in the trend of conductance spectrum is observed. • The underlying mechanism that induce the conductance spectrum difference is discussed. During the application of the electro-mechanical impedance (EMI) technique for detecting the strength development of concrete, in some cases, the piezoelectric sensor is embedded in the concrete. Normally, there are two methods to embed the piezoelectric sensor: PS-EMI and CPS-EMI. For both methods, the observed resonance frequency of the piezoelectric sensor increases with the increase of the concrete strength. However, there is a contradiction in the trend of conductance amplitude at the resonance frequency, which has to an extent puzzled the researchers in this area. In this paper, we developed a three-dimensional EMI model for the embedded piezoelectric sensor. We discussed the underlying mechanism, which induces the conductance spectrum difference for the PS-EMI and CPS-EMI, and experimental verification was carried out. By plotting the evolution of the concrete strength as a function of the resonance frequency shift, it was found that both embedding methods can be used in practical applications. [ABSTRACT FROM AUTHOR]

The Particle Image Velocimetry (PIV) technology was adopted to study the expansion ratio, solid holdup, minimum fluidization velocity, velocity field, turbulent kinetic energy, vortex structure and particle velocity of liquid-solid mini-fluidized beds with bed diameter of 1–3 mm. Due to the wall effect caused by the decrease of bed diameter, the axial velocity at the central axis was 1.68–1.93 times of that near the wall. Both liquid and particle phases had tendency to move toward the central axis of bed. When the liquid velocity gradually increased, the turbulence phenomenon appeared in the liquid-solid mini-fluidized bed. Regarding particles, their axial velocity was mainly influenced by the superficial liquid velocity, while the radial velocity was predominantly by vortices and friction between particles. In this study, the overall movement of flow field was comprehensively obtained, which provided a certain theoretical reference for the design of the liquid-solid mini-fluidized bed reactors. [Display omitted] • Particle fluidization and flow field characteristics were obtained by PIV method. • New Richardson-Zaki empirical equation constants (n and k) were determined. • Effects of experimental conditions on flow field characteristics were investigated. • Turbulence was found in the liquid-solid mini-fluidized beds. • The contributing factors of particle axial and radial velocity were discussed. [ABSTRACT FROM AUTHOR]

Recent experiments on sound waves in a unitary Fermi gas reveal many transport properties about strongly interacting fermions. Sound propagates through the coupling of momentum and heat transport, and attenuates strongly with the presence of a phase transition. In this work, focusing on the temperature regimes near and below the superfluid critical temperature T c in the BCS-BEC crossover, we present a Kubo-based microscopic calculation of thermal conductivity κ , which has not attracted much attention compared to the shear viscosity. Our approach primarily addresses the contributions of the fermionic quasiparticles to thermal transport and our results return to the kinetic descriptions at high temperatures. κ drops upon crossing the pseudogap temperature T ∗ , and its temperature dependence changes below T c . The drops become more pronounced on the weakly coupled BCS side, where the Pauli blocking causes the upturn of κ above T ∗ . Our calculations fit well with the sound measurement on the damping rate. [ABSTRACT FROM AUTHOR]

This paper discusses the binarization restoration algorithms of ancient Chinese Rubbings image. According to the location of the image features, such as color, edge, stroke width and pixel location feature, the binary restoration algorithm of digital rubbings based on threshold segmentation and morphology is discussed. If the difference between the text and the background is larger and more obvious distinguish in images, Otsu threshold segmentation method can be directly used. For images with more background noise, shadows and uneven illumination, threshold segmentation cannot achieve effective segmentation and reasonable denoising, a set of algorithms associated with the pixel position of adaptive segmentation, morphological method, connected domain and mean filtering combined of binarization restoration are needed. The experimental results show that this algorithm is very effective for image with complex and large area noise. [ABSTRACT FROM AUTHOR]

The bubble size distribution, phase holdups and mass transfer characteristics in a gas-liquid-solid circulating fluidized bed (GLSCFB) riser were simulated through the three-fluid (Euler-Euler-Euler) approach, the population balance model (PBM) and the gas-liquid mass transfer models. The three-fluid approach coupled with the PBM included the effect of bubble coalescence and breakage on the interphase forces, and gave good predictions on the bubble size distribution and the phase holdups. The bubble size distribution obtained from the PBM, together with the gas holdup, was used to calculate the gas-liquid interfacial area. For the mass transfer coefficient k l , the penetration model, the surface renewal model and the eddy cell model were tested and compared under varied superficial gas velocities, among which the eddy cell model provided the most reasonable prediction for k l. The effects of superficial gas, liquid velocities and particle circulating rate on the bubble size distribution, the phase holdups, the gas-liquid interfacial area, the mass transfer coefficient and the volumetric mass transfer coefficient were investigated numerically. It is concluded that the CFD-PBM coupled model, together with the eddy cell model could predict the hydrodynamics and mass transfer in a GLSCFB riser reasonably. Unlabelled Image • The three-fluid approach coupled with PBM is proposed in a GLSCFB riser. • This model can simulate bubble size distribution, phase holdups and interface area. • The eddy cell model is validated in predicting mass transfer characteristics. • The effect of operating conditions is investigated systematically. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Axial meso-scale model of gas-liquid-solid fluidization is established. • Momentum exchanges are quantified by bubble and particle accelerations. • Model can predict the axial distributions of all the flow parameters. • Model can predict the variation of transition with operation conditions. Abstract The meso-scale theory, based on the energy minimization multi-scale principle, has recently inspired the accurate modeling of the multi-phase flow. In this study, an axial meso-scale flow model for the gas-liquid-solid fluidized bed is established and verified by the literature models and data. Compared with the reported axial models, this model predicts the axial distribution of all three-phase hydrodynamic parameters with fewer empirical corrections. Predictions of the present model show that the operation conditions and physical properties of solid particles obviously affect the flow behaviors of phases, such as the slip velocity, entrainment of solid particles, wake shedding parameters. Solid particles entrained by bubble wake determine the formation of axial distribution in the gas-liquid-solid fluidized bed. Region with the axial structure is the transition section, length of which depends on the entrainment of solid particles. Furthermore, behaviors of the gas bubbles and the solid particles are mutually influential. [ABSTRACT FROM AUTHOR]

Mechanism modeling is an important method to quantify the flow heterogeneous phenomena of gas-liquid-solid fluidization. In this study, an improved meso-scale flow model, based on the energy minimum multi-scale (EMMS) theory, is developed to predict the global flow parameters of gas-liquid-solid fluidized bed. The improved EMMS model introduces gas bubble and solid particle accelerations, which make the model be capable of accurately predicting both the nominal-steady and the unsteady hydrodynamics of gas-liquid-solid fluidization. Compared with the reported models, the predicted results of this improved EMMS model are closer to the experiment data. Furthermore, the predictions indicate that both gas bubble acceleration and solid particle acceleration have an influence on the flow behavior of gas-liquid-solid fluidized bed, such as gas bubble diameter and relative slip velocity, which seriously affect the momentum and mass transfer between phases. Meanwhile, the accelerations of gas bubble and solid particle are not always equal to 0 at the nominal-steady state. Furthermore, the acceleration behavior of the unsteady-state gives a reasonable explanation for gas bubble coalescence. However, the relative error between model predictions and experimental data increases with the superficial gas velocity and the solid particle inertia. Thus this improved EMMS model is suitable for flow system at low superficial gas velocity with light and small solid particles. [ABSTRACT FROM AUTHOR]

Fe-Sn-O mixed oxides were synthesized and used as catalysts for of cyclohexanone, which showed both high and selectivity. X-ray and scanning suggested that the Fe-Sn-O catalysts had a tetragonal structure with a grain size of 29.3 nm. An ε-caprolactone yield as high as 98.8% was obtained in a small-scale experiment (5 mmol of cyclohexanone). In a scale-up test (20 mmol of cyclohexanone), the cyclohexanone conversion and ε-caprolactone yield were 96.7 and 96.5%, respectively. In addition, the catalysts can be reused five times without any major decline in . Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

• d 15 shear mode 1–3 type cement-based piezoelectric composites (CPC) is reported. • The influence of PZT volume fraction on the performance of CPC is investigated. • The influence of composite thickness on the performance of CPC is investigated. • The influence of cement matrix on the performance of CPC is investigated. In this work, we investigated the influence of PZT volume fraction, composite thickness and cement matrix on the performance of 1–3 connectivity cement-based piezoelectric composites working in d 15 shear mode. Results revealed that the piezoelectric strain coefficient d 15 and the relative dielectric coefficient ε r decrease with the decrease of the PZT volume fraction and increase with the increase of the composite thickness. The piezoelectric strain coefficient d 15 of the composite specimens with Phosphoaluminate cement (PALC) matrix is the largest, followed by Sulfoaluminate cement (SAC) matrix and Portland cement (PC) matrix. The relative dielectric coefficient ε r of the composite specimens with PC matrix is the largest, followed by PALC matrix and SAC matrix. The piezoelectric voltage factor g 15 increases with the decrease of the PZT volume fraction and decreases with the increase of the composite thickness. The piezoelectric voltage factor g 15 of the composite specimens with PC matrix is the smallest, and the values of specimens with SAC matrix and PALC matrix are very close. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mesoscale model of radial flow of gas-liquid-solid fluidization is established. • Effect of the liquid shear stress on the radial flow structure is quantified. • Radial peak position of liquid stress is between 0.75 and 0.9. • Radial peak position of energy consumed to fluidize particles is from 0.75 to 0.9. Gas-liquid-solid circulating fluidized bed (GLSCFB) is an important reactor. Radial hydrodynamics of GLSCFB are critical for the industrial design and scale-up, but the hydrodynamics have not been well described. To mechanically model the radial flow structures, a mesoscale method based on the energy-minimization multiscale principle is applied. A comparison between experimental data and model calculations shows that the radial mesoscale model can reasonably predict the radial distributions of the flow parameters and analyze the influence of the operating conditions on the radial hydrodynamics in GLSCFB for fluidizing solid particles of small diameters (d p ≤ 1 mm) and low solid holdup (ε s ≤ 15%). Additionally, model predictions show that the peak positions of the suspension and transportation energy consumed per unit mass of solid particles and liquid shear stress range from 0.75 to 0.9, which is an obvious indicator of the radial flow structure. [ABSTRACT FROM AUTHOR]

Based on an exact canonical partition function, we investigate the thermodynamics and trap-size scaling behaviors for a finite number of ideal bosons confined in a cubic box or in a harmonic trap. Both in the box trap imposed by either periodic or Dirichlet boundary conditions (BCs) and in the harmonic trap, we calculate several physical quantities including the chemical potential μ, specific heat C, condensate fraction 〈 n〉/ N, root-mean-square fluctuations δ n of the condensate population, and transition temperature T, and compare these quantities under different traps. We discuss the particle-number dependence of T through proposing several T definitions, where the differences among these values are considerable for the finite systems. [ABSTRACT FROM AUTHOR]

Recent experimental data suggest that for some 2:17 type magnets, the coercive field exhibit non-monotonic temperature dependence. As the temperature is increased, the switching field increases, attains a maximum, and then decreases. We study the effect of a reduction of the exchange for the spins in the pinning boundaries on the temperature dependence of the coercive field. In our model the pinning boundary consists of periodic arrays of faces of pyramids. Simulation results of non-monotonic temperature dependence of the depinning field is found, in agreement with experimental observation. We speculate that the pinning potential can change from repulsive to attractive as the temperature is increased. The location of the domain wall is also changed. [Copyright &y& Elsevier]

Remote ischemic perconditioning (RIPerC) results in collateral enhancement and a reduction in middle cerebral artery occlusion (MCAO) induced ischemia. RIPerC likely activates multiple metabolic protective mechanisms, including effects on matrix metalloproteinases (MMPs) and protein kinases. Here we explore if RIPerC improves neuroprotection and collateral flow by modifying the activities of MMP-9 and AMPK/e-NOS. Age matched adult male Sprague Dawley rats were subjected to MCAO followed one hour later by RIPerC (3 cycles of 15 min ischemia). Animals were euthanized 24 h post-MCAO. Haematoxylin and Eosin (H&E) staining 24 h post-MCAO revealed a significant (p < 0.02) reduction in the infarction volume in RIPerC treated animals (24.9 ± 5.4%) relative to MCAO controls (42.5 ± 4.2, %). TUNEL staining showed a 42.6% reduction in the apoptotic cells with RIPerC treatment (p < 0.01). Immunoblotting in congruence with RT-PCR and Zymography showed that RIPerC significantly reduced MMP-9 expression and activity in RIPerC + MCAO group compared to MCAO group (218.3 ± 19.1% vs. 148.9 ± 12.05% (p < 0.01). Immunoblotting revealed that RIPerC was associated with a significant 2.5-fold increase in activation of p-AMPK compared to the MCAO group (p < 0.01) which was also associated with a significant increase in the e-NOS activity (p < 0.01). RIPerC resulted in reduction of infarction volume, decreased apoptotic cell death and attenuated MMP-9 activity. This together with the increased activity of p-AMPK and increase in p-eNOS may, in part explain the neuroprotection and sustained increase in blood flow observed with RIPerC following acute stroke. [ABSTRACT FROM AUTHOR]

• Axial mesoscale model of gas-liquid-solid circulating fluidization is established. • Behavior of the particle-clusters dominates the axial hydrodynamics. • Acceleration of the particle-cluster determines the length of transition-section. • Model can predict the transition points between the different flow modes. • Shedding vortex contributes to the formation of the particle-clusters. This paper has established an axial meso-scale model based on the Energy-Minimization Multiscale (EMMS) principle for the gas-liquid-solid circulating fluidized bed. Comparisons made with the experimental data show that the established model is able to predict the axial hydrodynamics of the system under study. Model studies demonstrate that the dynamic formation and decomposition of the particle-clusters can illustrate the mechanism of the axial distribution. For the first time, the model predicts the transition points between the expanding fluidization mode, the circulating fluidization mode, and the liquid transporting mode. The maximum value of the solid particles' acceleration in the particle-cluster phase can be an indicator of a change to the length of the transition section. And the particle-clusters gradually form as the bubbles grow. In the pseudo steady state, the solid particles' acceleration in the liquid-solid suspension phase tends to be −9.8 m/s2, and that of the bubbles tends to be 0 m/s2. [ABSTRACT FROM AUTHOR]

In rock masses, there might be structural nonstationarity in the joint morphology that influences the shear behavior of rock joints. However, research into this effect is seldom reported. In this study, shear tests on artificial rock joints that contained stationary morphology and different nonstationary features were conducted. The experimental results showed that nonstationarity has a significant effect on the shear properties of rock joints. Under the action of lower normal stress levels, the peak shear strength of joints increased with the increase in the nonstationary angle, and it was easy for the slip behavior along the nonstationary trend to occur. Under higher normal stress levels, the damage to big areas in the upper and lower joint blocks, especially on the left and right ends of the joint surfaces, readily appeared. In this case, the nonstationary characteristics tended to be the main factor that controlled the damage to joints. The analysis revealed that after subtracting the nonstationary angle, the peak friction angles of the joints with nonstationarity were close to the peak friction angles of the joints with stationary morphology and provided the same normal stress. Therefore, the nonstationary angle and stationary joint morphology were separately but fully considered to describe the peak dilatancy angle. Using the proposed model for the peak dilatancy angle, a new criterion for the peak shear strength of joints that contained nonstationary features was established. Comparisons of the new criterion with the published criteria when estimating the peak shear strength of rough rock joints showed that the new criterion has a good prediction accuracy for rock joints with nonstationarity. [ABSTRACT FROM AUTHOR]

The k-nearest neighborhoods (kNN) of feature points of complex surface model are usually isotropic, which may lead to sharp feature blurring during data processing, such as noise removal and surface reconstruction. To address this issue, a new method was proposed to search the anisotropic neighborhood for point cloud with sharp feature. Constructing KD tree and calculating kNN for point cloud data, the principal component analysis method was employed to detect feature points and estimate normal vectors of points. Moreover, improved bilateral normal filter was used to refine the normal vector of feature point to obtain more accurate normal vector. The isotropic kNN of feature point were segmented by mapping the kNN into Gaussian sphere to form different data-clusters, with the hierarchical clustering method used to separate the data in Gaussian sphere into different clusters. The optimal anisotropic neighborhoods of feature point corresponded to the cluster data with the maximum point number. To validate the effectiveness of our method, the anisotropic neighbors are applied to point data processing, such as normal estimation and point cloud denoising. Experimental results demonstrate that the proposed algorithm in the work is more time-consuming, but provides a more accurate result for point cloud processing by comparing with other kNN searching methods. The anisotropic neighborhood searched by our method can be used to normal estimation, denoising, surface fitting and reconstruction et al. for point cloud with sharp feature, and our method can provide more accurate result comparing with isotropic neighborhood. [ABSTRACT FROM AUTHOR]

We investigate the dynamical evolution and atom number parity effect of bosonic condensates in a double-well potential within the two-mode Bose–Hubbard model (BHM), following a quench from the Josephson to the Fock regime. We demonstrate the different behaviors of systems with even and odd numbers of atoms on a mesoscopic scale by calculating the correlation function , visibility α, number fluctuation and entanglement entropy S. In contrast to the full collapse and revival of quantum correlations for systems with even numbers of atoms, we find that the correlations for systems with odd numbers will not collapse thoroughly, predicting a nonvanishing interference pattern. We relate this phenomenon to the parity effect of the energy spectrum, explain the effect in the pseudo-angular-momentum representation of the BHM Hamiltonian and suggest its confirmation in experiments. [ABSTRACT FROM AUTHOR]

Highlights • A meso-scale flow model for the gas-liquid-solid mini-fluidized bed was built. • Effect of the bed diameter (macro-scale) was introduced in the meso-scale model. • Constraint on the bubble coalescence was used for closing the meso-scale model. • Phase holdups and bubble size in mini-fluidized bed were determined by visual method. Abstract Experiments on the gas-liquid-solid mini-fluidized beds with sizes of 1.45 and 2.3 mm show that the bed diameter has a considerable effect on the phase holdups and gas bubble size, because the macroscopic dimension (macro-scale) in a mini-fluidized bed is close to the dimensions of bubbles (meso-scale) and particles (micro-scale). Hence, the parameter of bed diameter was introduced through the modifications on the energy-minimization multi-scale (EMMS) model for the conventional three-phase mini-fluidized beds to predict the flow behavior of three-phase mini-fluidized bed. These modifications include two correction factors for the liquid and bubble slip velocities and a constraint condition on the bubble coalescence. The correction on the liquid slip velocity is to estimate the effect of column shear stress on the distribution of liquid velocity. The other correction factor is for quantifying the column resistance on the bubble rise. The correction factors were determined by the empirical correlations obtained from the experiments. Similarly, the bubble coalescence constraint is a correlation on the bubble spacing under steady state condition and determined from the experimental data. The modified meso-scale model equations were closed by this constraint condition and the solution of the model met the principle of energy minimization. The model predictions and experimental data agree well within the investigation range of experimental conditions. [ABSTRACT FROM AUTHOR]

In order to investigate the regulation mechanisms of carotenoid biosynthesis in mango flesh, carotenoid content and the expression patterns of 15 carotenogenic gene in flesh of two mango cultivars ‘Tainong1’and ‘Hongyu’ were analsyed during fruit development and ripening. Carotenoid were increasingly accumulated during fruit growth and sharply incaresed during postharvest ripening in both cultivars. In ripe fruit, total carotenoid content in the flesh of ‘Tainong1’ was 177.16 ug/g (Fresh weight) FW, and for ‘Hongyu’ 36.24 ug/gFW. The major carotenoids in the flesh were β-Carotene and α-carotene,with minor carotenoids being β-cryptoxanthin, zeaxanthin, lutin and neoxanthin. RT-PCR analysis revealed that the expression of carotenogenic genes CRTISO , PSY , ZDS , BCH and ZEP were up-regulated in flesh, whereas the transcript levels of LCYB , LCYE and NCED were down-regulated in two cultivars and during fruit development and ripening. CRTISO , PSY , ZDS , BCH and ZEP transcripts were significantly positively correlated with the total carotenoids content, while no differences were detected for CRTISO expression between cultivars. These results suggested that PSY , ZDS , BCH and ZEP coordinately contribute to carotenoid accumulation during mango fruit development and ripening. [ABSTRACT FROM AUTHOR]

In 2019 and 2020, symptoms of dwarfing, yellowing, and reddening were observed in garlic in open fields in Shandong Province, China. Milk vetch dwarf virus (MDV) was detected in aphids and symptomatic garlic plants using polymerase chain reaction analysis. Furthermore, it was demonstrated using an aphid transmission test that garlic is a natural host of MDV. Rolling-circle amplification was combined with the use of specific primers to amplify the complete genomes of MDV and its related alphasatellites. This is the first report of complete genome sequences of MDV and related alphasatellites from garlic and aphid samples. [ABSTRACT FROM AUTHOR]

Finite-time cycle period for a quantum Otto machine implies that either an adiabatic stroke or an isochoric process proceeds in finite time duration. The quantum Otto refrigerators under consideration consist of two adiabatic strokes, where the system (isolated from the heat reservoir) undergoes finite-time unitary transformation, and two isochoric steps, where the system may not reach thermal equilibrium even at the respective ends of the two stages due to finite-time interaction intervals. Using two-time projective measurement method, we find the probability distribution functions of both coefficient of performance and cooling load, which are dependent on the time duration along each process. With these distributions we find the analytical expressions for the performance parameters as well as their fluctuations. We then numerically determine the performance and fluctuations for the refrigerator operating with a two-level system employed in a recent experimental implementation. Our results clarify the role of finite-time durations of four processes on the performance and fluctuations of the quantum Otto refrigerators. [ABSTRACT FROM AUTHOR]

In this study, a fluidized bed graphite tube evaporator with an internal vapor-liquid-solid flow boiling in the tube was established and the signals of vibration acceleration of the tube were measured. The attractors of the fluctuations of flow induced vibration acceleration were investigated by applying the chaos theory, and the evolving mechanism of the chaotic attractors of vapor-liquid-solid flow induced vibration signals at varied solid holdup and steam pressure was analyzed. The results indicate that the multiphase flow induced vibration has a chaotic nature. The chaotic attractor of the vibration acceleration signals can display the multiphase flow vibration behavior. Higher fluid mixture density and turbulent vapor bubble number result in denser, bigger and more complex chaotic attractor. Fluidized solid particles have an obvious influence on the vibration behavior of the graphite tube with internal vapor-liquid flow boiling. Unlabelled Image • Vibration of tube with internal vapor-liquid-solid flow boiling is chaotic. • The attractor of vibration acceleration signal appears as a regular trajectory. • Attractor characters vary closely with the tube vibration behavior. • Time delay value doesn't change with solid holdup of vapor-liquid-solid flow. • Fluidized solid particles have an obvious influence on tube vibration behavior. [ABSTRACT FROM AUTHOR]

• Formation and rise of single bubble in mini-fluidized was simulated. • Simulations were validated by experiments with good agreements. • Interactions between bubble and particles were explored. • Bubble wake size reduced with the increase of solid holdup in the simulation. The single bubble behavior in a 3 mm rectangular gas–liquid–solid mini-fluidized bed with 90 μm particles was simulated using the combination of VOF and DEM, and the results were validated by experiments. The simulation on the expansion of liquid–solid mini-fluidized shows that the profiles of liquid and particle velocities are consistent, and both become more concentrated as the expansion ratio decreases. The bubble formation size does not change with the increase of the solid holdup from 0.25 to 0.45, while the bubble rise velocity becomes lower. The upward liquid velocity in the bubble wake exceeds 50% of the instantaneous bubble velocity. The size of the low particle concentration bubble wake reducing with the increase of solid holdup can be attributed to the decrease in the bubble rise velocity and the enhancement in the inertia effect of the liquid–solid flow. [ABSTRACT FROM AUTHOR]

We investigate the dimensional crossover of Bose–Einstein condensation of atomic gases trapped in anisotropic harmonic potentials. The crossover from three dimension to lower dimensions is studied by calculating some thermodynamic quantities, such as critical temperature, heat capacity, entropy and atom number fluctuations in Bose–Einstein condensate. The smooth transition behavior indicates that a decimal dimension may be employed to describe the corresponding intervenient states. We compare the theoretical curves with recent experimental results on the fluctuations of the condensate atom numbers, revealing how the geometry and size of the condensates affect the thermodynamic characteristics. [ABSTRACT FROM AUTHOR]

Nano-phase nickel hydroxide samples were prepared by a method combining supersonic and coordination–precipitation methods. The samples exhibit β-phase Ni(OH)2 through X-ray diffraction analysis. It is shown that the grain size with the irregular grain shape is about 40 nm and ranges from 20 to 50 nm through transmission electron microscopy. Clustering phenomena were observed. The positive electrode discharge test made of a mixture of micrometer sized spherical Ni(OH)2 and nano-phase Ni(OH)2 was carried out. The results showed that the capacity of the electrode can be increased by about 14% when the nano-phase Ni(OH)2 doped concentration is 8 wt%. X-ray photoelectron spectroscopy analysis indicates that nano-phase Ni(OH)2 can increase the transformation between Ni3+ and Ni2+ in the charge–discharge cycle when the nano-phase Ni(OH)2 is doped, and as a result the utilization of active material on the positive electrode is improved. [Copyright &y& Elsevier]

We investigate the transition and damping of low-energy collective modes in a trapped unitary Fermi gas by solving the Boltzmann-Vlasov kinetic equation in a scaled form, which is combined with both the T-matrix fluctuation theory in normal phase and the mean-field theory in order phase. In order to connect the microscopic and kinetic descriptions of many-body Feshbach scattering, we adopt a phenomenological two-fluid physical approach, and derive the coupling constants in the order phase. By solving the Boltzmann-Vlasov steady-state equation in a variational form, we calculate two viscous relaxation rates with the collision probabilities of fermion's scattering including fermions in the normal fluid and fermion pairs in the superfluid. Additionally, by considering the pairing and depairing of fermions, we get results of the frequency and damping of collective modes versus temperature and s-wave scattering length. Our theoretical results are in a remarkable agreement with the experimental data, particularly for the sharp transition between collisionless and hydrodynamic behaviour and strong damping between BCS and unitary limits near the phase transition. The sharp transition originates from the maximum of viscous relaxation rate caused by fermion-fermion pair collision at the phase transition point when the fermion depair, while the strong damping due to the fast varying of the frequency of collective modes from BCS limit to unitary limit. [ABSTRACT FROM AUTHOR]