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Here we report on a new Early Cretaceous eutherian represented by a partial skeleton from the Jiufotang Formation at Sihedang site, Lingyuan City, Liaoning Province that fills a crucial gap between the earliest eutherians from the Yixian Formation and later Cretaceous eutherians. The new specimen reveals, to our knowledge for the first time in eutherians, that the Meckelian cartilage was ossified but reduced in size, confirming a complete detachment of the middle ear from the lower jaw. Seven hyoid elements, including paired stylohyals, epihyals and thyrohyals and the single basihyal are preserved. For the inner ear the ossified primary lamina, base of the secondary lamina, ossified cochlear ganglion and secondary crus commune are present and the cochlear canal is coiled through 360°. In addition, plesiomorphic features of the dentition include weak conules, lack of pre- and post-cingula and less expanded protocones on the upper molars and height differential between the trigonid and talonid, a large protoconid and a small paraconid on the lower molars. The new taxon displays an alternating pattern of tooth replacement with P3 being the last upper premolar to erupt similar to the basal eutherianJuramaia. Parsimony analysis places the new taxon withMontanalestes,SinodelphysandAmbolestesas a sister group to other eutherians.This article is part of the theme issue ‘The impact of Chinese palaeontology on evolutionary research’.

Monitor lizards (genusVaranus) are today distributed across Asia, Africa and Australasia and represent one of the most recognizable and successful lizard lineages. They include charismatic living species like the Komodo dragon of Indonesia and the even larger extinctVaranus prisca(Megalania) of Australia. The fossil record suggests that living varanids had their origins in a diverse assemblage of stem (varaniform) species known from the Late Cretaceous of China and Mongolia. However, determining the biogeographic origins of crown-varanids has proved problematic, with Asia, Africa and Australia each being proposed. The problem is complicated by the fragmentary nature of many attributed specimens, and the fact that the most widely accepted, and most complete, fossil of a stem-varanid, that ofSaniwa ensidens, is from North America. In this paper, we describe a well-preserved skull and skeleton of a new genus of stem-varanid from the Eocene of China. Phylogenetic analysis places the new genus as the sister taxon ofVaranus,suggesting that the transition from Cretaceous varaniform lizards toVaranusoccurred in East Asia before the origin and dispersal ofVaranusto other regions. The discovery of the new specimen thus fills an important gap in the fossil record of monitor lizards. The similar lengths of the fore- and hindlimbs in this new taxon are unusual among the total group Varanidae and suggest it may have had a different lifestyle, at least from the contemporaneous North AmericanS. ensidens.This article is part of the theme issue ‘The impact of Chinese palaeontology on evolutionary research’.

Scannerless time-of-flight three-dimensional imaging, the successor to raster scanning three-dimensional imaging, relies on large-scale detector arrays to obtain high pixel resolution; however, manufacturing limitations lead to a bottleneck in imaging resolution. Here, we report a methodology for laser imaging using code division multiple access, which involves three key steps. Optical encoding is carried out for a pulsed laser to generate space-time encoded beams for projection. Optical multiplexing subdivides the backscattered light signals and multiplexes them to a downscaled avalanche-photodiode array. Subpixel decoding decodes the digitized encoded full waveforms and decomposes the features of all subpixels. Accordingly, we design a prototype based on a 64-order encoder and a 4-element avalanche-photodiode array and conduct an outdoor experiment. We demonstrate that the system is capable of obtaining 256 pixels per frame in push-broom mode and reconstruct a three-dimensional image with centimetre-level lateral resolution and range precision at a distance of ∼112 m. Scannerless time of flight three-dimensional devices can produce high-quality images from the ground or in space and provide information on light detection and ranging. The authors design and demonstrate a downscaled subpixel 3D laser imaging device which uses pulse-encoded illumination to encode the pixels.

In this paper, the influence by the pixel shape to crosstalk in autostereoscopic display is analyzed. The diffraction is greatly influenced by the shape of pixels and structure of multi-view autostereoscopic display. It diffracts at sides of sub-pixels, which is more serious at the shorter side. By simulating the light intensity distribution of viewing zones at best viewing distance, we calculate the crosstalk caused by diffraction. The simulation results show that the ratio of the horizontal and vertical spacing of the pixel which is equal to the ratio of the vertical and horizontal spacing of the central bright fringe, which means that the shorter sides are, the worse influence it has on quality of exit pupils. The influence makes exit pupils wider than it should be, and increases crosstalk, leading to viewing discomfort. We propose a solution by horizontal sub-pixels. It indicates that crosstalk by diffraction can reduce to 3.13% in simulation.

Separate layer water injection is an effective way to alleviate the contradiction between layers. During the extra high water cut stage, the oil-water percolation capacity changed significantly, which leads to the increase of seepage difference in various oil layers. The interlayer interference is more prominent. The method of combining water injection intervals according to static parameters such as permeability and small layer thickness is difficult to meet the need of accurate water injection in the period of extremely high water cut. Therefore, the characteristic of seepage resistance in different water-cut stages is analyzed based on the oil-water two-phase relative permeability curve. The idea of water injection interval combination is changed from similar permeability in the middle and high water cut period to similar percolation resistance in the extremely high water cut period. The influencing factors of seepage resistance between oil and water wells are analyzed. Based on the principle of water and electricity similarity, the calculation method of seepage resistance in each small layer of injection well is established. The boundary of variable coefficient of seepage resistance is determined by numerical simulation. A new method of interval combination with the aim of minimizing the coefficient of variation of seepage resistance is established. The application effect of this method shows that the potential number of interval combination adjustment wells can be increased more than 30% in the water control and efficiency improvement test area of Daqing Changyuan Oilfield. After implementing the optimal combination of 10 injection wells, the water cut of the connected production wells decreased 0.2% and the production increased 606t, achieving a good effect of oil increase and water control in the context of 96% water cut. This method provides an effective method to control water cut rise and production decline in extra high water cut old oilfield.

A Correction to this paper has been published: https://doi.org/10.1038/s42005-021-00520-8.

Architecture of expressway network tolling platform is put forward based on GIS+BIM, real-time tolling fee calculation for each vehicle in networked and prewarning of equipment and facilities as well as data analysis and mining are studied, the basic network diagram of GIS+BIM is presented, and the database and data dictionary are researched. Platform performance requirements such as high efficiency of calculation of fee, transparency of business management, data identification, high fault tolerances of storage, and rapid response are studied. The research of this paper will provide certain reference for the construction of expressway tolling system.

Dexmedetomidine (Dex) was reported to reduce ischemia-reperfusion (I/R) injury in kidney and brain tissues. Thus, we aimed to study the role and mechanism of Dex in cerebral I/R injury by inhibiting hypoxia-inducible factor-1α (HIF-1α) and apoptosis. First, I/R injury models were established. Six groups were assigned after different treatments: sham, I/R, I/R+Dex, I/R+2-methoxyestradiol (2ME2) (HIF-1α inhibitor), I/R+CoCl 2 (HIF-1α activator), and I/R+Dex+CoCl 2 groups. Neurological function, cerebral infarction volume, survival, and apoptosis of brain cells were then analyzed. Besides, immunohistochemistry and Western blot analysis were used to detect the expression of HIF-1α, BCL-2[B-cell leukemia/lymphoma 2] adenovirus E1B interacting protein 3 (BNIP3), B-cell leukemia/lymphoma 2 (BCL2), BCL2[B-cell leukemia/lymphoma 2] associated X (Bax), and cleaved-caspase3 proteins in brain tissues. I/R rats showed cerebral infarction, increased neurological function score, number of terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL)-positive cells and HIF-1α-positive cells as well as decreased neurons. Inhibition of HIF-1α can reduce the apoptosis induced by I/R, and overexpression of HIF-1α can aggravate apoptosis in brain tissue of I/R rats. Furthermore, activation of HIF-1α expression blocks the inhibitory effect of Dex on neuronal apoptosis in I/R rats. Dex may inhibit the neuronal apoptosis of I/R rats by inhibiting the HIF-1α pathway and then improve the cerebral I/R injury in rats.

A novel luminol electrochemiluminescence (ECL) strategy based on TiO 2 /CNTs nanocomposites for detection of glucose was developed. First, the TiO 2 /CNTs nanocomposites were prepared by a sol-gel method and modified on the glass carbon electrode. The ECL signal could be greatly enhanced after the electrode was modified with TiO 2 /CNTs nanocomposites, which finally resulted in the increased sensitivity. Glucose oxidase can react with glucose to form H 2 O 2 , and then the H 2 O 2 reacts with luminol to produce the ECL signal. Thus the above system is proved to be efficient for glucose detection. The modified electrode exhibited excellent ECL signals and gave a good linear range over 1.0 × 10 –7 –5.0 × 10 –6 M with a detection limit of 5.2 × 10 –8 M towards glucose detection. This strategy was successfully demonstrated as a sensitive, rapid, simple and cost-effective method for the determination of glucose. Meanwhile, the TiO 2 /CNTs nanocomposites offered a novel material for the signal enhancement in electrochemiluminescence sensor.

The wind tunnel test was carried out for the Sightseeing Tower of the West Taihu Lake, Changzhou in this study, and the equivalent static wind loads of the Moon Tower were obtained at different wind angles. Frequency-domain analysis was performed to reveal the wind-induced response dynamics. The distribution diagram of unfavorable equivalent static wind loads was worked out to provide reference for the design of the main structure.

Wartsila RT-flex 60C diesel engine is selected as the object to research pressure control of fuel common rail system, building the system simulation model, and analyzing main factors influencing rail pressure in the system. it was concluded that they were diesel engine speed, load. In the process of MATLAB/Simulink simulation, the rail pressure control logic was designed by adopting maps with the two factors as independent variables to get theory feedforward quantity of fuel rack, feedback quantity of fuel rack is obtained by fuzzy PID control. The simulation experiments show that the improved control method reduces the rail pressure fluctuation, at the same time the overshoot volume of dynamic rail pressure control is greatly reduced, response velocity quickened. The control method has been used in a Marine simulator.

A switchable autostereoscopic 3-dimensional (3D) display device with wide color gamut is introduced in this paper. In conjunction with a novel directional quantum-dot (QD) backlight, the precise scanning control strategy, and the eye-tracking system, this spatial-sequential solution enables our autostereoscopic display to combine all the advantages of full resolution, wide color gamut, low crosstalk, and switchable 2D/3D. And also, we fabricated an autostereoscopic display prototype and demonstrated its performances effectively. The results indicate that our system can both break the limitation of viewing position and provide high-quality 3D images. We present two working modes in this system. In the spatial-sequential mode, the crosstalk is about 6%. In the time-multiplexed mode, the viewer should wear auxiliary and the crosstalk is about 1%, just next to that of a commercial 3D display (BENQ XL2707-B and View Sonic VX2268WM). Additionally, our system is also completely compatible with active shutter glasses and its 3D resolution is same as its 2D resolution. Because of the excellent properties of the QD material, the color gamut can be widely extended to 77.98% according to the ITU-R recommendation BT.2020 (Rec.2020).

Facing to the problem of hierarchical structure decision analysis which is made of scheme level + factor level + target level, the analytic hierarchy process gives a whole set of solution and process. This method is used to evaluate diesel engine simulation model. Evaluate original mean value model of large-scale low-speed marine diesel engine and the new one by this method. Calculated results prove this method is applicable.

In order to provide the basis for quality standard and processing principle of processed Asari Radix et Rhizoma, an HPLC fingerprint of processed Asari Radix et Rhizoma was established and the contents of methyl eugenol and asarinin were determined.The analytical column was Agligent Tc-C18 (250 mm x 4. 6 mm, 5 µm); A mixture of acetonitrile-0. 2% acetic acid solution was used as the mobile phase with gradient elution at the flow rate of 1. 0 mL/min. The wavelength was set at 285 nm and the column temperature was 30 °C.The fingerprint of processed Asari Radix et Rhizoma was established. The asarinin peak was taken as the reference peak. 22 common peaks were assigned, and two peaks were confirmed by comparing with the reference standards. The difference of components was not significant among the various processed products except ginger, honey and fried coke products, but the contents of effective constituents were different among the processed products. The retention rate of methyl eugenol in processed products was in a descending order as follows: winevinegarliquoricealkali-vinegarfried cokerice water systemhoneygingersalt systemalkali. Methyl eugenol was increased 10% ~ 20% with wine processing and retained more than 95% with vinegar. The retention rate of asarinin in processed products was in declining as: rice water systemliquoricealkali-vinegarhoneysalt systemwinegingervinegaralkalifried coke. The processing techniques increased the content of asarinin except the alkali and fried coke products, and asarinin was increased more than 35% with rice water, alkali-vinegar or liquorice processing.The method is accurate and reliable, which can be used for the quality control of processed products of Asari Radix et Rhizoma.

Remote sensing robot technology is an emerging research area, which attains a development in recent years. In this paper, the definitions of remote sensing and robot remote sensing will be discussed, and then the remote mines detection technology of RAT-1 eight-wheeled robot, the application of IR-optical sensor in mobile robot for detection and source location of gas leakage, the monitoring of environment intelligent robot on environment and the positioning of mobile robot on targets and other focuses are emphatically introduced, and finally the important problems in each application as well as possible development of remote sensing robot technology are proposed.

The combined connection with welds and bolds can be widely used in reinforcing the joint in steel structure. In this paper, proposed design method of combined connection with bolts and longitudinal welds was given based on the tests and finite element analysis (FEA). The method considers the effect of the strength ratio between bolts and welds. The safety and reliability of the method were verified by FEA and comparison with other design method. The design method can contribute to the promotion of the application of the combined connections.

The combined connection with welds and bolds has advantages of both welds and bolts connections, and can be widely used in reinforcing the joint in steel structure. In this paper, the Finite Element Method (FEM) was taken to analyze the carrying capacity of the combined connection with bolts and welds, and the results ware compared with those come from experimental investigation. Further analysis based on FEM ware performed to research the failure mode and bearing performance of the combined connection and the contribution of bolts and welds .Advice was provided for related design.

Highway bridges played an important role in lifeline systems. Their seismic damage status made a direct influence on the implement plan of the earthquake relief work and the life and property security of the people. Therefore, accurate assessment and prediction for the seismic damage of highway bridges were of vital significance, based on which reasonable earthquake fortification could be implemented. This paper summarized and classified the existing seismic damage assessment methods for highway bridges, including certain index evaluation methods based on statistical results, vulnerability index evaluation methods based on probability theory and vulnerability index evaluation methods based on aggregation model. Then the capacity-spectrum method which could be used for calculating the fragility curve and the seismic assessment model of highway bridges used in HAZUS were specially explained. At last, the proposal for the development of seismic assessment systems related with highway bridges in China was put forward. Considering HAZUS’s good performance in seismic assessment, a similar assessment system should be built in China as soon as possible. The first step should be classifying highway bridges in China based on their current situation and obtaining their seismic assessment model parameters roughly, which tend to be safe. The second step should be carrying out sufficient experiments and numerical analysis and revising the model parameters obtained in the first step.

The quality of virtual view based on multi-view video (MVD) plus depth format is often evaluated by PSNR or subjectively judged. However, due to synthesizing arbitrary view images, the virtual view images mostly have no reference images and are only assessed using non-reference. Virtual view images synthesized by depth estimation reference software (DERS) and view synthesis reference software (VSRS) often accompanied with blockiness and other distortions on the edge. In addition, matching level for the depth map and the corresponding texture maps of left and right views also affects the quality of the virtual view. This paper compares the edge similarity of the depth and the corresponding texture maps which generate the intermediate virtual view and combined with the virtual view’s blockiness which causing blur to evaluate the quality of the virtual view. Experiment results show that the proposed method can reflect the quality of the virtual view better.

Depth maps are used for synthesis virtual view in free-viewpoint television (FTV) systems. When depth maps are derived using existing depth estimation methods, the depth distortions will cause undesirable artifacts in the synthesized views. To solve this problem, a 3D video quality model base depth maps (D-3DV) for virtual view synthesis and depth map coding in the FTV applications is proposed. First, the relationships between distortions in coded depth map and rendered view are derived. Then, a precisely 3DV quality model based depth characteristics is develop for the synthesized virtual views. Finally, based on D-3DV model, a multilateral filtering is applied as a pre-processed filter to reduce rendering artifacts. The experimental results evaluated by objective and subjective methods indicate that the proposed D-3DV model can reduce bit-rate of depth coding and achieve better rendering quality.

A typical three-story unstiffened Steel Plate Shear Wall (SPSW) finite element model was established. Systematic parameters analysis of the development and changing process of the lateral stiffness and shear capacity was mainly carried on the middle standard layer. The result shows that the lateral stiffness of thin SPSW has been always in decline and has a higher shear capacity after buckling. According to lots of analysis data and different stages of lateral control targets in the new revised seismic design code for performance designing, the lateral limits of the SPSW were respectively qualified under wind loads and frequent earthquake.The test verification was also proposed to verify the restrictive lateral limits so as to supply a scientific basis for the preparation of SPSW design method.

Composite slab with steel sheeting deck is considered a continuous slab when it is under a constructional situation. Nevertheless, many recent researches are focused on simply supported slab. In order to determine the load carrying capacity regarding various rebar ratio on negative moment region, a numerical analysis was carried out by using finite element analysis. The result of analysis shows that the reinforced steel rebar increases load carrying capacity. Moreover, it has shown that the reinforced length of steel rebar also affect the load carrying capacity.

The section of the column under axial compression used in a certain electrostatic precipitator is composed of double H shaped steel limbs and the stiffened connecting web by weld. As the width of connecting web usually exceeds 3 times of the section height of H shaped steel, the axis which connecting web lies in is the weaker axis for the stiffness of column section, while the midperpendicular of connecting web is the stronger axis. In consideration of initial geometrical imperfections and weld residual stresses, the study on stability round the stronger axis of column subjected to axial compression by nonlinear finite element method is conducted. The research results indicate that the column doesn’t present the flexural buckling round the stronger axis, but present the elasto-plastic flexural-torsional buckling. A buckling factor is produced to measure the stability performance of column round stronger axis. When the connecting channel shaped steels between two limbs and the stiffeners located on connecting web are strengthened, the buckling factor increases slightly. When the width-thickness ratio of connecting web increases, the buckling factor decreases significantly. When the slenderness of H shaped steel round the stronger axis is kept constant and the height-thickness ratio of H-shaped steel web increases, the buckling factor increases. Based on a great many computation results, the regressed recommendation is proposed how to evaluate the design buckling bearing capacity of column under axial compression round stronger axis.

To explore the component difference of the serum containing essential oil from Yin Teng Gu Bi Kang prescription in pathologic and physiologic rat models, and to reveal the material basis of its efficacy of activating blood circulation.The essential oils were obtained by CO2 supercritical fluid extraction and the ingredients of the essential oils in vitro and in vivo (under physiological and pathological status) were analyzed by GC-MS to compare differences of the essential oil under physiological and pathological status in rats.32 components were identified with the main components of Z-ligustilide (39.23%) and d-limonene (21.7%) in the essential oil. In vivo analysis on the essential oil indicated that 16 components were identified, 7 existed originally in essential oil and 9 were metabolites under physiological status; while 22 components were identified, 10 existed originally in essential oil and 12 were metabolites under pathological status (acute blood stasis). There were 7 common prototypes and 8 common metabolites under different physiological status.The absorption and metabolism of essential oils were affected by blood stasis and the compounds migrating to blood may be the effective substance in activating blood circulation.