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The discrete unified gas kinetic scheme (DUGKS) is a multiscale approach, which can be used to obtain reasonable results in all flow regimes. The key of this method is the reconstruction of numerical fluxes at the cell interface by coupling the motion of particles from their collisions, namely the use of the discrete characteristic solution to the Boltzmann-BGK equation at the cell interface to calculate numerical fluxes. But like all the discrete velocity methods (DVMs), the computational cost of DUGKS is determined by the discretization in both the physical space and the velocity space. For the continuous flow region in the computational domain, the discretization in the velocity space is unnecessary since the distribution function can be reconstructed from the Chapman-Enskog expansion directly. To improve the efficiency of DUGKS in capturing cross-scale flow physics, an adaptive partitioning-based discrete unified gas kinetic scheme (ADUGKS) is developed in this work. The ADUGKS is designed from the discrete characteristic solution to the Boltzmann-BGK equation, which contains the initial distribution function and the local equilibrium state. The initial distribution function contributes to the calculation of free streaming fluxes and the local equilibrium state contributes to the calculation of equilibrium fluxes. If the contribution of the initial distribution function is negative., the local flow field can be regarded as the continuous flow and the Navier-Stokes (N-S) equations can be used to obtain the solution directly. Otherwise, the discrete distribution functions should be updated by the Boltzmann equation to capture the rarefied effect. Given this, the computational domain is divided into the DUGKS cell and the N-S cell based on the contribution of the initial distribution function to the calculation of free streaming fluxes. In the N-S cell, the local flow field is evolved by solving the Navier-Stokes equations, while in the DUGKS cell, both the discrete velocity Boltzmann equation and the corresponding macroscopic governing equations are solved by a modified DUGKS. Since more and more cells turn into the N-S cell with the decrease of the Knudsen number, a significant acceleration can be achieved for the ADUGKS in the continuum flow regime as compared with the DUGKS.

To investigate the prevalence of mountain-type zoonotic visceral leishmaniasis (MT-ZVL) in Yangquan City, Shanxi Province from 2015 to 2020, so as to provide the scientific evidence for formulating the MT-ZVL control strategy.The epidemiological data pertaining to MT-ZVL cases in Yangquan City from 2015 to 2020 were collected and descriptively analyzed. A Joinpoint regression model was created to analyze the trend in the MT-ZVL incidence in Yangquan City from 2015 to 2020 using annual percent change (APC). The sandflies surveillance data and the prevalence ofA total of 162 MT-ZVL cases were reported in Yangquan City, Shanxi Province from 2015 to 2020, with annual mean incidence of 1.9/10The prevalence of MT-ZVL appeared a tendency towards a rapid rise in Yangquan City from 2015 to 2020, and systematic interventions are urgently needed for MT-ZVL control.

To characterize the species of invasiveA total of 104 livingThis is the first report of invasive

In this work, the explicit formulations of the Grad's distribution function for the 45 moments (G45)-based gas kinetic scheme (GKS) are presented. Similar to the G13 function-based gas kinetic scheme (G13-GKS), G45-GKS simulates flows from the continuum regime to the rarefied regime by solving the macroscopic governing equations based on the conservation laws, which are widely used in conventional Navier-Stokes solver. These macroscopic governing equations are discretized by the finite volume method, where the numerical fluxes are evaluated by the local solution to the Boltzmann equation. The initial distribution function is reconstructed by the G45 distribution function, which is a higher order truncation of the Hermite expansion of distribution function compared with the G13 distribution function. Such high order truncation of Hermite expansion helps the present solver to achieve a better accuracy than G13-GKS. Moreover, the reconstruction of distribution function makes the development of explicit formulations of numerical fluxes feasible, and the evolution of the distribution function, which is the main reason why the discrete velocity method is expensive, is avoided. Several numerical experiments are performed to examine the accuracy of G45-GKS. Results show that the accuracy of the present solver for almost all flow problems is much better than G13-GKS. Moreover, some typical rarefied effects, such as the direction of heat flux without temperature gradients and thermal creep flow, can be well captured by the present solver.

Bridges across navigation channels are under the threat of accidental ship collisions. Many research works have been conducted to investigate the crashworthy device against ship-bridge pier collisions. However, the existing bridge pier protection facilities, mostly based on absorbing ship kinetic energy, are large structures with high strength, resulting in large collision forces that may cause ship damage. In this paper, flexible anti-collision technology is developed, which protects the bridge pier based on the ship's course guidance principle, hence taking away the huge kinetic energy of the ship in the process of collision. The pier flexible crashworthy device has a compact structure and can greatly reduce the impact force of ships, protecting both the bridge and the ship. The reliability and effectiveness of the technology have been verified through off-shore impact tests.

An efficient improved discrete velocity method (IDVM) with inner iteration is presented to simulate the steady flows in all flow regimes in this work. It is an extension of our previous implicit IDVM to achieve a faster convergence rate. In the previous method, both the discrete velocity Boltzmann equation (DVBE) and the corresponding macroscopic governing equations are solved synchronously, where the computational discrete cost is dominated by the calculation of the DVBE since the number of distribution functions is far larger than that of macroscopic conservative variables. Furthermore, the convergence rate of the calculation of the DVBE is affected by the predicted equilibrium state obtained from the solution of macroscopic governing equations. To provide a more accurate predicted equilibrium state for the fully implicit discretization of the DVBE, an inner iteration is introduced into the solution of macroscopic governing equations, and the flux Jacobian of these equations is evaluated by the difference of numerical fluxes of Navier–Stokes equations rather than the Euler equation-based flux splitting method used in the previous implicit IDVM. This more accurate prediction procedure endows the developed method to accelerate the computation greatly, especially in the continuum flow regime. Numerical results indicate that, in the continuum flow regime, the present method is about one order of magnitude faster than the previous implicit IDVM and one to two orders of magnitude faster than the conventional semi-implicit DVM.

Objectives Infectious Zika viral particles were detected in human milk; however, whether they can be transmitted via breastfeeding remains unknown, so our objective was to clarify this. Methods Here, in a natural breastfeeding model, wild-type (C57Bl/6; WT) or interferon α/β (IFNα/β) receptor-deficient (A129; KO) murine dams on day 1 post-delivery were infected with Zika virus (ZIKV) intraperitoneally, and the neonates were suckled. In a novel artificial feeding model, WT suckling mice at 1 day old were fed with ZIKV alone or ZIKV and human breast milk mixtures. Thereafter, the virus distribution, clinical progression and neuropathology in the WT or KO neonates were characterized to evaluate the risk of ZIKV transmission through breast milk. Results In natural breastfeeding, viral RNAs (8/8) and infectious viral particles (7/8) were extensively present in the mammary glands of KO dams. All tested KO neonates (5/5), and none of WT neonates (0/9), were infected with ZIKV. In artificial feeding, 100% of the WT neonates (two groups, 12/12 and 16/16) were infected and developed some signs of neurodegeneration. ZIKV tended to seed and accumulate in the lungs and were subsequently disseminated to other tissues in both 16 naturally suckled and 19 artificially fed infected neonates. As human breast milk was mixed with ZIKV and fed to WT neonates, 45% individuals (9/20) were infected; in the infected neonates, the viral spread to the brain was delayed, and the clinical outcomes were alleviated. Conclusions These results demonstrated that suckling mice can be infected with ZIKV through suckling, and breast milk has potential antiviral activity, inhibiting ZIKV infection.

To explore the effect of LncRNA MEG3 in the subarachnoid hemorrhage (SAH) and its underlying mechanism.The expressions of lncRNA MEG3 in SAH patients and animal model were detected by quantitative real-time PCR (qRT-PCR). After LncRNA MEG3 was overexpressed in neurons by lentivirus, viability and apoptosis abilities were detected by cell counting kit-8 (CCK-8) assay, flow cytometry, and TUNEL assay, respectively. The apoptosis-related genes and Pi3k/Akt pathway-related proteins were further detected by a Western blot.The expressions of lncRNA MEG3 in SAH patients were remarkably higher than normal controls, which were positively correlated with SAH severity. After lncRNA MEG3 overexpression, neuronal cell activity was decreased and cell apoptosis was increased. Moreover, the expressions of Bax, p53, and cleaved Caspase-3 were increased, whereas the expression of Bcl-2 and Pi3k/Akt pathway-related proteins were decreased after lncRNA MEG3 overexpression.LncRNA MEG3 is up-regulated in SAH, which may promote SAH-induced neuronal cell injury via inhibition of the Pi3k/Akt pathway.

To improve the accuracy of binocular 3D image reconstruction, the grid-pattern structure lines are printed on the detected objects and the grid lines intersection points are adopted as feature points and primitives in matching process. In this paper, a novel method for detecting the intersection points of the grid lines based on image segmentation and ridge line fitting is proposed. Firstly, the set of line segments on the border of the grid lines are extracted using the Canny edge detector and Hough transformation. Then, the global structure parameters are acquired through cluster analysis. Secondly, the grayscale image is divided into several detection regions (each of which includes one intersection point to be detected) in accordance to the obtained global structure parameters and the intersection points in the detection regions are accurately located using the ridge line fitting method. Finally, the intersection points in the left and right images are matched based on their distributions. To examine the detection performance of the proposed method, experiments have been conducted on actual and polluted images, respectively. The experimental results have demonstrated that the recognition ratio of the intersection points by the proposed ridge line fitting-based method is as high as 100%, the false positive ratio is 0 and the matching accuracy is up to 100%. Compared with the results obtained using traditional methods, the proposed method detection results are characterized by high accuracy, stability, uniqueness and invariability. Hence, the proposed method can meet the demands of 3D image reconstruction

Boron-doped diamond single crystal was synthesised from Fe–Ni–C–B system at 1773 K and 5.6 GPa for 10 minutes. The crystal shape, structure and morphology of boron-doped diamonds were studied using X-ray diffraction, atomic force microscopy and field emission electron microscopy. Results showed that the {111} faces of boron-doped diamond are prevailing. Field emission electron microscopy and atomic force microscopy analysis indicate the terrace-like and zigzag growth steps both present on (100) and (111) facets with the terrace-like steps are dominant on (100) crystal plane, and the height of the steps is in the range from 3.10 to 5.02 nm. The step's growth is proposed to result from the boron atom incorporation.

A boundary condition-implemented immersed boundary-lattice Boltzmann method (IB-LBM) is presented in this work. The present approach is an improvement to the conventional IB-LBM. In the conventional IB-LBM, the no-slip boundary condition is only approximately satisfied. As a result, there is flow penetration to the solid boundary. Another drawback of conventional IB-LBM is the use of Dirac delta function interpolation, which only has the first order of accuracy. In this work, the no-slip boundary condition is directly implemented, and used to correct the velocity at two adjacent mesh points from both sides of the boundary point. The velocity correction is made through the second-order polynomial interpolation rather than the first-order delta function interpolation. Obviously, the two drawbacks of conventional IB-LBM are removed in the present study. Another important contribution of this paper is to present a simple way to compute the hydrodynamic forces on the boundary from Newton’s second law. To validate the proposed method, the two-dimensional vortex decaying problem and incompressible flow over a circular cylinder are simulated. As shown in the present results, the flow penetration problem is eliminated, and the obtained results compare very well with available data in the literature.

Spinal cord injury (SCI) is typically caused by trauma or disease, and it severely affects patients' motor function. The relationship between signal transducers and activators of transcription-1 (STAT1) and neuronal death after cerebral focal ischemia has been comprehensively studied, but its role in SCI remains largely unknown. This study investigated the protective effect of an STAT1 inhibitor on SCI. Thirty SD rats were SCI-induced and were then randomly divided into two groups (N = 15 each), either receiving STAT1 or the STAT1 inhibitor S1491 by intraperitoneal injection. The motor dysfunction of the rats was evaluated by behavioral scores, followed by the examination of SCI by hematoxylin and eosin staining. Apoptosis was also detected by Western blot and terminal deoxynucleotidyl transferase-mediated dUTP nick-end-labeling (TUNEL) assay. The motor functions of rats receiving STAT1 did not score as well as the STAT1 inhibitor group (P < 0.01). Further assays showed remarkable improvements in pathological damage to spinal code tissue in STAT1 inhibitor-treated rats, along with lower Bax and higher Bcl-2 expression. The STAT1 inhibitor also suppressed the occurrence of TUNEL-positive cells compared to the STAT1-treated group. In summary, we suggest that the STAT1 inhibitor alleviates SCI by decreasing apoptosis.

This paper at first shows the details of finite volume-based lattice Boltzmann method (FV-LBM) for simulation of compressible flows with shock waves. In the FV-LBM, the normal convective flux at the interface of a cell is evaluated by using one-dimensional compressible lattice Boltzmann model, while the tangential flux is calculated using the same way as used in the conventional Euler solvers. The paper then presents a platform to construct one-dimensional compressible lattice Boltzmann model for its use in FV-LBM. The platform is formed from the conservation forms of moments. Under the platform, both the equilibrium distribution functions and lattice velocities can be determined, and therefore, non-free parameter model can be developed. The paper particularly presents three typical non-free parameter models, D1Q3, D1Q4 and D1Q5. The performances of these three models for simulation of compressible flows are investigated by a brief analysis and their application to solve some one-dimensional and two-dimensional test problems. Numerical results showed that D1Q3 model costs the least computation time and D1Q4 and D1Q5 models have the wider application range of Mach number. From the results, it seems that D1Q4 model could be the best choice for the FV-LBM simulation of hypersonic flows.

Background Numerous studies have demonstrated the ability of body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR) and waist-to-height ratio (WHtR) to predict the risk of type 2 diabetes mellitus (T2DM) and cardiovascular diseases (CVD). This study aimed to evaluate the predictive value of these anthropometries for metabolic abnormalities and related diseases in Chinese adults. Material & methods A cross-sectional study was conducted in 2 477 men and 3 107 women at 20-79 years old who were randomly selected from Pudong New Area of Shanghai, China, through a multistage sampling process. Anthropometric variables and blood pressure were measured according to a standardized protocol, and a fasting blood sample was collected from each subject for biochemical analysis. Results Prevalence of the metabolic syndrome was observed to increase with increasing BMI, WC, WHR and WHtR in both sexes. Participants with any metabolic abnormality had a higher body size than those without. The associations of anthropometries with each metabolic factor were significant and equal for BMI, WC, WHR and WHtR. Areas under the receiver operating characteristic curves (AUC) ranged from 0.59 to 0.72 across the 4 anthropometries in predicting individual and clusters of metabolic factors. However, none of the 4 anthropometries identified newly-diagnosed T2DM or hypertension with a high sensitivity or specificity. Conclusion Our findings suggest that the independent use of BMI, WC, WHR, or WHtR may not be an effective tool to predict metabolic factors and related chronic diseases in Chinese adults.

With 1 figure and 3 tables Abstract Applied stress is often used to induce embryogenesis in microspore culture. Cold pretreatment has been used in cereal crops, Brassica napus and Brassica rapa microspore cultures, but seldom attempted in Brassica oleracea microspore culture. In this study, the effect of cold pretreatment (4°C) on embryogenesis in microspore culture and ploidy of regenerants resulting from those cultures was investigated in three broccoli cultivars ‘Green Elite’, ‘Green Star’ and ‘TI-111’. Cold pretreatment for 1, 2 or 3 days was effective when applied alone using these three cultivars, but the frequency of embryos derived from microspores was low. The combination of cold pretreatment (4°C) for 1 or 2 days and heat shock (32.5°C) for 1 day significantly enhanced microspore embryogenesis efficiency, especially with ‘TI-111’ for which it was increased by 63–72-fold. In addition, the combined treatment resulted in higher diploid frequency of the regenerated population compared to traditional microspore culture protocol which typical only uses heat shock at 32.5°C for 1 day in broccoli.

In this study, we employed a regional model to simulate the impact of urban expansion on monthly climate in Pearl River Delta (PRD) region. Two experiments were performed by prescribing two different land covers in the PRD region. One land cover represents vegetation in the 1970s which is derived from the United States Geological Survey (USGS) data with 24-category (hereafter referred to as NU). The other land cover represents the current urban condition which is derived from remote sensing data acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) in 2004 (hereafter referred to as HU). Using the two land cover datasets, monthly climate of October 2004 was simulated, which was a very dry season in the PRD region. The results obtained from the numerical simulation show a distinct difference in simulated shelter-level temperature, humidity, surface fluxes and the height of planetary boundary layer (PBL) with two different land cover data sets being specified. The maximum difference in simulated monthly mean temperature over urban areas was 0.9 °C. A large temperature difference was found in urbanized area in Guangzhou, Dongguan, Zhongshan and Shenzhen. The monthly mean relative humidity in urban areas decreased by 1.4% as a result of urban expansion (from 59.2% in NU to 57.8% in HU). The maximum decrease in mixing ratio was 0.4 g/kg in Guangzhou and Dongguan, whereas the maximum decrease in relative humidity was 2.4%. There was an increase of sensible heat flux in developed lands and the maximum increase was 90 W m−2. In contrast, latent hear flux in urban area decreased and the maximum decrease was 300 W m−2. In addition, the increase in mean height of PBL ranged from 20 to 80 m (HU compared with NU), and the maximum change of the height was 180 m over urban area in city of Guangzhou.

Torque measuring in the extra-high rotation speed has not been resolved ideally yet, due to the restriction of the rough conditions. The dynamic characteristics of the developed digital plane grating angular-torquer measuring system are analyzed in this paper. The paper mainly calculates and designs the parameters of elastic shafts with different cross-section. Via the compare of dynamic characteristics and compactness of the elastic shafts with different cross-section, the optimized design is proposed at the end of the paper. The achievements of this paper can supply references to the study and design, maintaining and improvement of relative instruments.

We have used our analysis of γ-γ-γ data (5.7 × 1011 triples and higher folds) taken with Gammasphere from prompt γ rays emitted in the spontaneous fission of 252Cf to study the collective bands in 104,106,108Mo. The one-phonon and two-phonon γ-vibrational bands and known two-quasiparticle bands in neutron-rich 104,106Mo were extended to higher spins. The one-and two-phonon γ-vibrational bands have remarkably close energies for transitions from the same spin states and identical moments of inertia. Several new bands are observed and are proposed as quasiparticle bands in 104,106Mo, along with the first β-type vibrational band in 106Mo. The quasiparticle bands have essentially constant moments of inertia near the rigid-body value that indicate blocking of the pairing interaction. Candidates for chiral doublet bands in 106Mo are strong. These are the first reported chiral vibrational bands in an even-even nucleus.

High-spin states in neutron-rich 106Mo were investigated by detecting the prompt γ-rays in the spontaneous fission of 252Cf with Gammasphere. Several new bands are observed. Two sets of ΔI = 1 bands in 106Mo are found to have all the characteristics of a new class of chiral vibrational doublets. Tilted axis cranking calculations support the chiral assignment and indicate that the chirality is generated by neutron h11/2 particle and mixed d5/2, g7/2 hole coupled to the short and long axis, repectively.

High spin states in the odd–odd nucleus 122Cs have been studied by in-beam γ-ray spectroscopy with a 107Ag(19F,1p3n) fusion-evaporation reaction at a beam energy of 85 MeV. A previously known πh11/2 ⊗ νh11/2 yrast band was confirmed and its spin I was re-examined. A ΔI = 2 band was identified, which together with another known ΔI = 2 band forms a side band of the πh11/2 ⊗ νh11/2 yrast band. The two observed πh11/2 ⊗ νh11/2 bands are proposed as a pair of chiral doublet bands in 122Cs based on a systematic comparison with those in the neighbouring odd–odd Cs isotopes, as well as the relativistic mean field and the triaxial particle-rotor-model calculations.

We suggest a flexible platform based on waveguides for constructing metamaterial functional components which work in the terahertz waveband. The properties of the components can be changed by selecting the specified metamaterial resonance structures on the waveguide's narrow wall. In the paper, metallic circular patches are used as resonance structures to design the functional component which can be configured as a filter or absorber. The simulation and experimental results demonstrate that the component's attenuation and absorption bandwidth can be configured by changing the quantities and sizes of the resonance structures.

Recent evidence suggests that common functional polymorphisms in the hypoxia inducible factor-1α (HIF-1α) gene may play an important role in the development and progression of digestive cancer, but individually published results are inconclusive. Our meta-analysis is aimed to derive a more precise estimation of the relationships between HIF-1α gene polymorphisms and digestive cancer risk. An extensive literature search for relevant studies was conducted on Pubmed, Embase, Web of Science, Cochrane Library, and CBM databases from their inception through May 1, 2013. This meta-analysis was performed using the STATA 12.0 software. The crude odds ratios (OR) with 95% confidence interval (CI) were calculated. Eight case-control studies were included with a total of 1276 digestive cancer patients and 3392 healthy controls. Our meta-analysis revealed that the A variant of HIF-1α G1790A polymorphism might be associated with increased risk of colorectal, esophageal, gastric, and liver cancers, especially among Asian populations. However, no statistically significant associations were found between HIF-1α C1772T polymorphism and susceptibility to digestive cancer. No publication bias was detected in this meta-analysis. The current meta-analysis suggests that the HIF-1α G1790A polymorphism may increase the risk of colorectal, esophageal, gastric, and liver cancers, especially among Asian populations.

The human umbilical cord represents a promising resource of mesenchymal stem cells (MSCs). In order to improve our understanding of MSCs derived from human umbilical cord (UC-MSCs), we isolated UC-MSCs from human umbilical cord tissues through a direct culture approach. We performed a comprehensive characterization of these cells based on analyses of morphology, growth features, cell surface antigen markers and differentiation capacity. All these analyses validated their stem cell nature. The UC-MSCs presented a spindle-shaped morphology and could be subcultured for up to 15 passages without losing their cellular features. Moreover, these UC-SMCs presented an expression profile of cell surface antigens similar to other MSCs: positive for CD44, CD90, and CD105 expression and negative for CD34, CD31, and CD45 expression. Differentiation assays further validated the multipotency of UC-MSCs by inducing these cells into osteoblasts, adipocytes and functional hepatocytes. Our studies clearly demonstrated that UC-MSCs resemble other types of MSCs in many aspects and have a great potential to be applied in tissue engineering and regenerative medicine.