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The impacts of merging on mixed traffic flow in the highway on-ramp zone are numerically investigated in this paper. An on-ramp mixed traffic flow merging model is proposed. Our model focuses on the on-ramp merging zone and considers a mixed traffic flow comprising of connected and automated vehicles (CAVs) and human-driven vehicles (HDVs). Firstly, we establish the Velocity-Modified Comfortable Driving (V-MCD) model for HDVs, which incorporates a velocity estimation module into the base Modified Comfortable Driving (MCD) model. The Cooperative Adaptive Cruise Control (CACC) model developed by PATH Labs is used for CAVs. A cooperative merging model has been developed to capture the interaction behavior of vehicles in various driving scenarios. Merging rules are established based on vehicle type and merging order. The merging rules for HDV-HDV are based on safety gap. Meanwhile, those for CAV-HDV are based on velocity difference, and for CAV-CAV are based on first-come-first-served. We conduct numerical simulation experiments to derive the fundamental diagram of the mixed flow and analyze the interaction between vehicles on the on-ramp and mainline. The simulation results indicate that the V-MCD model can effectively reflect on the hysteresis effect caused by on-ramp merging vehicles in real traffic scenarios. The increase in CAV penetration improves road traffic efficiency in terms of both traffic velocity and capacity. However, as the penetration of CAVs continues to rise, their positive impact will diminish. The sensitivity analysis of the hysteresis effect at both micro and macro levels can enhance our understanding of the impacts on traffic flow. As the hysteresis effect increases, merging has a greater impact on mainline upstream traffic, leading to reduce headway and more erratic velocity changes. [ABSTRACT FROM AUTHOR]

The NaCl-type La monopnictides are proper reference materials for the study of strongly correlated rare-earth pnictides. Yet, despite the simple crystal structure of this system, traditional density functional theory (DFT) calculations have dramatic failures in describing their electronic properties: DFT severely underestimates the band gaps and thus predicts incorrect transport characters of them. Here, we perform a corrected DFT calculation to rectify this failure. Our results show that LaN, LaP, and LaAs are semiconductor with band gaps of 0.82, 0.25, and 0.12 eV, respectively, and LaSb is semimetallic with an overlap of conduction and valence bands approximately 0.28 eV, in agreement with the available experiments. Additionally, under high-pressure, we find that LaN displays a new sequence of phase-transition, B1→anti-B10→B2, which is different from the previous theoretical predictions but consistent with the recent experiment. [ABSTRACT FROM AUTHOR]

In the traffic flow of most small-medium cities, there are a lot of two wheel vehicles which are mainly made up of human-powered bicycle, electric bicycle and motorcycle with different maximum speed and acceleration. A two-dimensional cellular automaton (CA) model for two-wheel vehicle mixed traffic flow based on NS model (A classical traffic CA model firstly introduced by Nagel and Scheckenberg in 1992) is built. In this model, the situation that the pedestrian cross the two-wheel vehicle road is also taken into consideration. The rules of lane-changing for two-wheel vehicles are set up according to the driving features of two-wheel vehicles. These rules consider the state of the front and back vehicles on current lane and the adjacent lanes (left and right sides) in current and next time step, which make the model more truthful. By performing numerical simulation, the influences on flow, speed and density of two-wheel vehicle by the elements such as deceleration probability, lane changing probability, the mixed ratio of all kinds of two-wheel vehicles, pedestrian crossing, are analyzed. Comparison with empirical data verifies the feasibility and effectiveness of this model. [ABSTRACT FROM AUTHOR]

A detailed theoretical method for studying the local lattice structure of Mn2+ ions in the (MnF6)4- coordination complex is presented. Based on the complete energy matrices for a d5 configuration ion in a tetragonal ligand field, the relationship between the defect structure and the zero-field splitting (ZFS) parameters are derived. By analysing the ZFS parameters of Mn2+ located at the tetrahedral site in the K2MgF4 crystal, the local lattice structure of the K2MgF4:Mn2+ system was investigated. From our calculations, local lattice structure parameters R1 = 2.0385A and R2 = 2.0558A at room temperature (295 K) and R1 = 1.9253A and R2 = 1.9329A at low temperature (4.2 K) were determined. [ABSTRACT FROM AUTHOR]

The optical absorption and EPR spectra of Mn2+ ion doped in cadmium maleate dihydrate have been theoretically investigated by diagonalizing the complete energy matrices for a d5 configuration ion in a trigonal ligand-field. According to the suggestion of the optical absorption studies, we assume that the Mn2+ ion enters the host lattice interstitially and the distorted octahedral symmetry for the impurity ion is trigonal. Moreover, the local lattice structure parameters of the system are determined. The results show that the six oxygen ions around the Mn2+ ion are at the same distance R=2.115 Å, and there are three Mn-O bonds forming an angle θ1 of 66.26° with the C3-axis and three others forming an angle θ2 of 43.40°. [ABSTRACT FROM AUTHOR]

The complete energy matrices $\left( {252\times 252} \right)$ for a d5configuration ion in a tetragonal ligand-field has been constructed on the basis of the complete set of basis $\left| {L,S,M_L ,M_S } \right\rangle $ of d5configuration (252 dimension), and the relationship between the low-symmetry EPR parameters b2 0 ,b4 0 and the local distortion parameters has been established based on the complete energy matrices. As an application, we have studied the EPR parameters and the local lattice structure of Mn2+ ion doped in tetragonal K2ZnF4 system. The calculation indicated that the local lattice structure around a tetragonal Mn2+ ion center has an expansion distortion. Simultaneously, the local lattice structure parameters R1 =2.0727 Å, R2 =2.0801 Å at room temperature (295 K) and R1 ′ = 2.0439 Å, R2 ′ =2.05478 Å at low temperature (4.2 K) are determined. [ABSTRACT FROM AUTHOR]

The anisotropy spin-orbit coupling matrices for a d5 configuration ion in a trigonal ligand-field have been established. On basis of the anisotropy spin-orbit coupling matrices, the ground state zero-field splitting of the Fe3+ ions in ilmenite-structure MgTiO3:Fe3+ system has been studied. The calculated results show that the anisotropy of Fe3+ ions in the diamagnetic ilmenite MgTiO3 is important and the EPR parameters depend sensitively on the anisotropy divergent parameter. Moreover, the effect of the anisotropy divergent parameter on the second-order parameter D is obviously larger than that on the fourth-order parameter (a-F). Based on this point, the local lattice structure of Fe3+ ion in MgTiO3:Fe3+ system is determined by diagonalizing the complete energy matrices for a d5 configuration ion in a trigonal ligand-field and considering the second-order as well as the fourth-order EPR parameters D and (a-F) simultaneously. Our results are consistent with the experimental proposal that Fe3+ ions may locate at both the Mg2+ and Ti4+ sites. [ABSTRACT FROM AUTHOR]

Objective: To analyze the clinical characteristics of 6 children with TTC21B-related nephronophthisis to provide reference for early clinical diagnosis. Methods: The general condition, clinical manifestations, laboratory tests and other clinical data of 6 children from 4 families diagnosed with nephronophthisis by genetic testing in Shanghai Children's Hospital from January 2015 to December 2020 were analyzed retrospectively. Results: A total of 6 children (3 males and 3 females) developed proteinuria and progressive renal dysfunction in early infancy. The onset age of proteinuria was 18 (6, 25) months. The age at the onset of renal impairment was 22 (10, 36) months. All 6 children progressed to end-stage renal disease (ESRD) within 10 (4, 65) months of onset. Five children had hypertension, 3 children with abnormal liver function, 2 children with visceral translocation and 1 child with growth retardation. The genetic results suggested that all children carried variations TTC21B gene p.C518R. Conclusions: Children with TTC21B gene p.C518R nephronophthisis had proteinuria and progressed to ESRD at the early stage of life. These nephronophthisis patients commonly presented with liver and renal dysfunction.

Objective: To clarify the correlation of the expression of glia maturation factor-β (GMF-β) with Ki-67 in astrocytoma, and to investigate the prognostic implications of combined detection of GMF-β and Ki-67. Methods: One hundred and forty human astrocytoma samples (WHO Ⅱ-Ⅳ grade) were collected at Southwest Hospital, Army Medical University (the Third Military Medical University), China from 2006 to 2009. Clinicopathological information and 3-year follow-up data were collected. Expression of GMF-β and Ki-67 was detected by single and double immunohistochemical staining, then the association of GMF-β expression with Ki-67 and its significance in prognostic evaluation of astrocytoma were statistically analyzed. Results: GMF-β expression in astrocytoma cells was correlated to both tumor grade and Ki-67 (both P <0.05); Kaplan-Meier survival analysis showed that GMF-β and Ki-67 expression were negatively correlated to the 3 year-survival rates, respectively (both P <0.01). Further analysis demonstrated that the two factors were co-influenced on survival, showing a trend of "GMF-β low Ki-67 low >GMF-β high Ki-67 low >GMF-β low Ki-67 high >GMF-β high Ki-67 high " in 3-year survival rate with significant intergroup differences ( P <0.05, P <0.01). Conclusions: GMF-β expression is positively associated with Ki-67 in astrocytoma. Combined detection of GMF-β and Ki-67 can predict prognosis of patients with glioma.

Objective: To investigate the value of MRI in the early diagnosis of diagnosis of dysbaric osteonecrosis. Methods: Labor hygiene investigation and occupation health were examined on 52 high pressure operating personnel, were selected for the examination of both shoulders, hips and knees with X-ray and CT scan. Results: The cystic sign in dysbaric osteonecrosis as an important imaging feature, which perform in the MRI examination for T1W I sequence showed low or slightly low signal and T2W I sequence showed high signal, and X-ray and CT have a lower detection rate than MRI. The Kappa consistency test showed a high consistency with the two methods. At the same time MRI examination also can discover the bone marrow cavity necrosis early pathological change. Conclusion: MRI is an effective method for the diagnosis of early dysbaric osteonecrosis, which can improve the early diagnosis rate of dysbaric osteonecrosis.

Objective: To explore the clinical features and expression of PLA(2)R in renal tissue of children with idiopathic membranous nephropathy. Methods: Retrospective study was performed in patients with membranous nephropathy diagnosed through renal biopsy and the follow-up time was at least half a year in Shanghai Children ' s Hospital from January 2010 to February 2017. We compared their clinicopathological and pathological findings of IMN. Indirect immunofluorescence assay was used to detect glomerular PLA(2)R expression. We analyzed the differences of clinical features between the PLA(2)R negative and positive groups. T test, rank-sum test and Fisher exact test were used. Results: Eleven cases had hematuria and proteinuria, 9 cases presented with nephrotic syndrome, and 2 cases showed isolated proteinuria. Of the 22 cases of children with IMN, 16 patients had complete remission (complete remission rate was 72.8%), and 22 patients had partial remission. The renal function of all cases was normal and in all cases the estimated glomerular filtration rate was > 90 ml/(min·1.73m(2)). Of 22 cases with IMN, 7 cases were PLA(2)R-positive in renal tissue and 15 cases were PLA(2)R-negative. The age of positive group (10 years old) was older than the negative group (6 years old)( Z= -2.483, P< 0.05) and the time of positive group (6 months) for urine protein to return to negative was longer than the negative group (2.5 months) through treatment. These differences were significantly different ( Z= -2.072, P< 0.05). Conclusions: Hematuria and proteinuria can be found in most children with idiopathic primary membranous nephropathy. Prednisone combined with immunosuppressant was effective. The positive rate of PLA(2)R in renal tissue of children with IMN was about 32%. The age of PLA(2)R positive group was older than the negative group. And the time of urine protein turning to negative in positive group was longer than that in the negative group.

Objective: To investigate the differential expression profiles of long non-coding RNAs (lncRNAs) in human liver cell line LO2 with stable expression of hepatitis B x (HBx) gene, and to screen out the lncRNAs which play an important role in HBV-related liver cancer., Methods: The lncRNA microarray was used to establish the differential expression profiles of lncRNAs, and the methods such as scatter plots and cluster analysis were used to obtain the HBx-related lncRNAs with differential expression. The qRT-PCR was used to verify some lncRNAs with differential expression. The t-test was used to compare the expression of lncRNAs between the two microarray groups, and hierarchical cluster analysis was used for the original data of lncRNAs with differential expression., Results: Compared with the control group transfected with blank plasmids (L02/pcDNA3.0), LO2/HBx cells had 323 lncRNAs with > 2-fold upregulation and 421 lncRNAs whose expression was reduced by more than 50% (P < 0.05). The results of qRT-PCR verified 4 upregulated lncRNAs (TCONS&#95;00006195, ENST00000557524, NR&#95;037597, and ENST00000539975) and 3 downregulated lncRNAs (ENST00000508424, ENST00000447433, and uc001lva.4), which were consistent with the results of microassay., Conclusion: HBx-related lncRNAs are successfully screened out, which lays a foundation for further investigation of the role of lncRNAs in the pathogenesis of liver cancer.

Purpose: To study the effects of exposure to compressed air on tunnel workers' health and to investigate the prevalence of dysbaric osteonecrosis (DON) in caisson workers., Methods: 128 tunnel workers were divided into the exposed group (n = 58) and the control group (n = 70), and their shoulders, hips and knees were examined with X-ray, computed tomography (CT) and magnetic resonance imaging (MRI)., Results: 1) 34.5% of the exposed group were diagnosed with DON based on the national diagnostic criteria of decompression sickness. 2) The incidental difference of skeletal cystic changes between the exposed group and the control group was highly statistically significant (p < 0.01). 3) CT and MRI examination could detect early onset of DON lesions, and the cystic changes shown in CT and abnormal signals in MRI were diagnostic indicators in cases., Conclusion: Cystic changes in CT and abnormal signals in MRI are key imaging findings of early DON.

To explore the possible oxidative stress induced by lead, heparinized whole blood and urine of 66 secondary smelter lead workers (46 for Comet assay) and 28 controls were collected. The concentrations of blood lead (BPb) and urinary lead (UPb) and alpha-aminolevulinic acid (alpha-ALA), indices of lead exposure level of the body, were determined. Malondialdehyde (MDA) concentrations and superoxide dismutase (SOD) activity of plasma were also measured. Single-cell gel (SCG, Comet assay) was used to measure the DNA damage of peripheral blood cells. There was a positive correlation between the presence of Pb in blood and significant increases in MDA levels and SOD activity. Alcohol consumption and smoking with increased exposure to Pb was associated with enhanced DNA damage. A positive correlation was found between MDA and DNA damage.