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Anterior cervical corpectomy and fusion (ACCF) has been widely used in the treatment of cervical spondylotic myelopathy (CSM) but is accompanied by unavoidable motion loss and destruction of vertebra. We aim to evaluate the range of motion (ROM) of caprine cervical spine constructs implanted with cervical artificial disc and vertebra system (ADVS). The purpose of this study was to investigate the biomechanical properties of the ADVS from an in vivo caprine cervical spine non-fusion model.

At present, although the new energy vehicle experience center presents a dynamic development trend of science, technology, diversity and innovation, the display and dissemination of the new energy vehicle industry and culture cannot be satisfied, resulting in the display function cannot be fully exerted. VR (Virtual Reality) display design is a new topic of audio–visual​ design with the popularization of VR technology and related computer application technology. This paper focuses on the realization and application of VR exhibition space design for new energy vehicles, and discusses the design principles that should be followed in VR exhibition space design for new energy vehicles and its practical significance to design communication. In this paper, a parallel 3D reconstruction method based on multi-view video stream is proposed. In this method, the mobile terminal and the server execute asynchronously, the terminal decodes the multi-view video stream in parallel, and the server performs feature extraction and stereo matching on the returned key frames. Finally, the calculated parallax is combined with the projection matrix to restore the 3D scene.

The sea‐ice extent (SIE) in the Weddell Sea plays a crucial role in the Antarctic climate system. Many studies have examined its long‐term trend, however whether its year‐to‐year variation has changed remains unclear. We found an amplified year‐to‐year variance of the Weddell Sea SIE in austral summer since 1998/1999 in observational datasets. Analyses of sea‐ice concentration budget and surface fluxes indicate that it is the thermodynamic process that drives the amplification of SIE variations, rather than the sea‐ice‐drift‐related dynamic process. Compared to 1979–1998, the Southern Annular Mode in the preceding spring shows a closer linkage with the Weddell Sea SIE in 1999–2021 through a stronger and more prolonged impact on sea surface temperature, which thermodynamically modulates local sea ice via changing surface heat and radiation fluxes. Our study helps advance the understanding of extreme low Antarctic‐SIE records occurring in recent decades and improve future projections of the Antarctic sea‐ice variability. Unlike Arctic sea ice, which has significantly declined in recent decades, Antarctic sea ice possesses a moderate increase with large spatial and seasonal discrepancies. The amount of austral‐summer sea ice extent (SIE) around the Antarctica exhibits more pronounced year‐to‐year variations in the 21st century. Interestingly, we found that the amplified SIE variation is most significant in the Weddell Sea, east of the Antarctic Peninsula. This amplified variations in Weddell Sea SIE apparently cannot be fully explained by anthropogenic forcing, suggesting an important role of internal variability in the Antarctic climate system. Our analyses showed that the late‐1990s changes in the Southern Annular Mode (SAM)—the predominant mode of climate variability in the extratropical Southern Hemisphere—might cause the interdecadal amplification of the summer sea‐ice variation in the Weddell Sea via the thermodynamic process. The year‐to‐year variability of summer sea‐ice extent in the Weddell Sea, Antarctica, has significantly increased since 1998/1999This interdecadal change in sea‐ice extent is dominated by changes in thermodynamic process rather than dynamic and mechanical processesThe Southern Annular Mode contributes to such a sea‐ice change via altering sea surface temperature and thus local thermodynamic processes The year‐to‐year variability of summer sea‐ice extent in the Weddell Sea, Antarctica, has significantly increased since 1998/1999 This interdecadal change in sea‐ice extent is dominated by changes in thermodynamic process rather than dynamic and mechanical processes The Southern Annular Mode contributes to such a sea‐ice change via altering sea surface temperature and thus local thermodynamic processes

The tropical easterly jet (TEJ) is an easterly jet stream that occurs from the upper troposphere to lower stratosphere in boreal summer. Owing to its wide vertical extension from 300 to 70 hPa, the TEJ may exhibit distinct characteristics at different levels, the details of which remain thus far unclear. In this study, two empirical orthogonal function (EOF) modes of the year-to-year variability in the vertical structure of the TEJ were investigated. The leading EOF mode represents a consistent strengthening or weakening of the TEJ's main body in the vertical direction and varies on both interannual and interdecadal time scales. It has been suggested that ENSO can modulate this vertically consistent mode interannually, whereas the Atlantic Multidecadal Oscillation and Pacific Decadal Oscillation can influence its interdecadal variability. In contrast, the second EOF mode exhibits an out-of-phase relationship between the zonal wind anomalies of the upper troposphere and lower stratosphere, linked with the changes in the TEJ's vertical movement and dominating on the quasi-biennial time scale. The Quasi-Biennial Oscillation could contribute to variations in the TEJ's vertical movement by changing the tropopause winds as a direct pathway and inducing anomalous convection over the tropical Indian Ocean and Maritime Continent as an indirect pathway.

Summer weather extremes (e.g., heavy rainfall, heat waves) in China have been linked to anomalies of summer monsoon circulations. The East Asian subtropical westerly jet (EASWJ), an important component of the summer monsoon circulations, was investigated to elucidate the dynamical linkages between its intraseasonal variations and local weather extremes. Based on EOF analysis, the dominant mode of the EASWJ in early summer is characterized by anomalous westerlies centered over North China and anomalous easterlies centered over the south of Japan. This mode is conducive to the occurrence of precipitation extremes over Central and North China and humid heat extremes over most areas of China except Northwest and Northeast China. The centers of the dominant mode of the EASWJ in late summer extend more to the west and north than in early summer, and induce anomalous weather extremes in the corresponding areas. The dominant mode of the EASWJ in late summer is characterized by anomalous westerlies centered over the south of Lake Baikal and anomalous easterlies centered over Central China, which is favorable for the occurrence of precipitation extremes over northern and southern China and humid heat extremes over most areas of China except parts of southern China and northern Xinjiang Province. The variability of the EASWJ can influence precipitation and humid heat extremes by driving anomalous vertical motion and water vapor transport over the corresponding areas in early and late summer.

This study investigated the influence of the stratospheric quasi‐biennial oscillation (QBO) on the tropical easterly jet (TEJ), using the ERA5 and QBO series of Singapore and Freie Universität Berlin. Since the 1980s, the easterlies of the TEJ over the Maritime Continent are weaker during easterly QBO (EQBO) than westerly QBO. QBO influences TEJ by affecting convection on the east and west sides of the Maritime Continent. The climatological rising movement on the west side of the Maritime Continent can reach a higher altitude than that on the east side, which implies the convections on the west side are likely to be more effectively promoted by the reduced stability near the tropopause during EQBO. The zonal asymmetry in the stability near the tropopause is also a possible cause for QBO modulating convection. QBO has a significant influence on the Asian summer monsoon and tropical/subtropical precipitation through modulating the TEJ. The tropical easterly jet (TEJ) is an essential component of the Asian monsoon system. Quasi‐biennial oscillation (QBO) is a phenomenon characterized by quasi‐periodic oscillation in the tropical stratospheric wind field. The opposite east‐west wind directions in the lower stratosphere during different phases of QBO are accompanied by opposite temperature and stability anomalies around the tropopause. Due to the different heights of the rising movements on the east and west sides of the Maritime Continent, their responses to the change of upper tropospheric stability caused by QBO are different. Responding to the change of the rising movement, the TEJ over the Maritime Continent during easterly QBO is significantly weakened compared with westerly QBO, and the decreased magnitude of easterly QBO can reach 11% of the climatological TEJ. The change of TEJ has a significant influence on the Asian summer monsoon and the precipitation in densely populated agricultural areas. The relationship between QBO and TEJ has recently emerged since the 1980s possibly due to climate change. Considering that QBO has a relatively robust periodicity, the relationship between QBO and TEJ has potential merit for long‐range prediction of TEJ and weather systems related to the Asian monsoon system. Tropical easterly jet (TEJ) is weakened over the Maritime Continent during easterly quasi‐biennial oscillation (QBO) since the 1980sThe zonal asymmetries in the convection, stability, and Kelvin waves are possible causes for QBO modulating TEJQBO influences the Asian summer monsoon and tropical/subtropical precipitation via TEJ over the Maritime Continent Tropical easterly jet (TEJ) is weakened over the Maritime Continent during easterly quasi‐biennial oscillation (QBO) since the 1980s The zonal asymmetries in the convection, stability, and Kelvin waves are possible causes for QBO modulating TEJ QBO influences the Asian summer monsoon and tropical/subtropical precipitation via TEJ over the Maritime Continent

To determine the range of motion and stability of the human cadaveric cervical spine after the implantation of a novel artificial disc and vertebra system by comparing an intact group and a fusion group.

The specific analysis of a region’s energy needs to model and simulate various types of energy, quantify energy information, and clearly and intuitively reflect the energy situation and energy potential of a region. In this paper, according to the input attributes of various energy load forecasting models, the correlation degree of main control factors is analyzed, and the influence degrees of environmental factors on electric power, gas, heating and cooling loads are obtained respectively. Then, convolution neural network is used to extract the feature vectors of comprehensive environmental factors. Finally, according to the given feature vectors, the feature clustering models of various energy loads are established by using K-means clustering algorithm, and the load forecasting results of multi-energy systems are obtained. The errors between the predicted results of various energy loads and the actual load records in the study area are 1.105%, 1.876%, 3.102% and 2.834%, respectively. The load forecasting method based on feature clustering proposed in this paper can effectively extract the influence of different environmental factors on the load forecasting results, and get more accurate load forecasting results.