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Landslide No.3 in Fei'e Mountain is located in the Shunde District of Foshan City, Guangdong Province, and its' lithology is mainly composed of pre-Cretaceous Baizushan Formation (K1b) argillaceous siltstone. In this study, engineering geological drilling, geophysical exploration, geological mapping, and indoor testing were used to determine that it is a medium-scale bedding rocky landslide with a typical double-layer deep sliding surface. The maximum length of the landslide body is approximately 220 m in the longitudinal (south-west) direction and approximately 230 m in the horizontal (north-west) direction; the maximum thickness is approximately 32m, and the attitude of sliding surface is 230°∠12°-17°. Landslide body tensile cracks, including nine large-scale tensile cracks, are very well-developed. The longest crack is approximately 120 m long and has a crack opening width of 0-13 cm, with a height difference between the two sides of the crack (rupture wall) of 0-0.2 m. The ground of the leading edge of the landslide was uplifted and cracked, with a maximum uplift height of approximately 1.7 m. The landslide shear outlet was clearly visible and exhibited well-developed scratches. The scratch direction was the same as the main slide direction of the underlying landslide. Landslide deformation severely cracked the building structure and obstructed the drainage channel. There was a loose residual soil layer on the surface of the slope of Landslide No.3, and many fractures and joints were present in the lower bedrock. During rainfall, rainwater penetrated the deep part of the slope along the rock layer surface, joints, and fractures, which greatly increased the bulk density of the rock and soil mass, and softened the argillaceous siltstones, which greatly decreased their shear strength. The excavation of the slope formed a steep surface, which reduced the load at the foot of the slope and thus reduced the anti-sliding force. During long-term seepage, the rock and soil mass near the landslide face was softened to form a weak zone mixed with joints and stratigraphic phases. During long periods of heavy rain, the weak zone became soaked, soft, and plastic, which reduced its shear strength. When downward force increased, the effective anti-sliding force of the weak zone was greatly reduced, resulting in a landslide. During this process, Landslide No.3 developed two slip surfaces. The maximum buried depths of slip surfaces 1 and 2 (corresponding to landslides 1 and 2) were 32 and 15.5 m, respectively, which means that landslide 2 overlaid landslide 1 and slip surface 1 creeping occurred before that of slip surface 2. The trailing edge of slip surface 1 developed a fissure, the characteristics of which are described above. As the fracture surface was not fresh, its' development time is unknown. As in the sliding process, landslide 2 first formed a continuous sliding surface, and its' sliding rate was slightly greater than that of landslide 1, landslide 2 was the first to cut out from the steep ridge of the landslide's front edge. As a result of the shearing action of landslide 2, landslide 1 developed multiple vertical cracks. Rainwater seeping down these cracks further lubricated slip surface 1, which resulted in drum mounds and cracks in the leading edge of the landslide. Slip surface 1 subsequently formed a continuous sliding surface, and Landslide No.3 entered the uniform deformation stage. Timely emergency measures prevented landslide deformation damage and halted landslide progression before entering the accelerated deformation stage. Considering its double-layer slip surface structure, a comprehensive combination of slope cutting, an anchor (cable), lattice beam, double-row prestressed anchor-pulling anti-slip pile, three-dimensional mesh grass greening, interception, drainage, and a hairy stone retaining wall was used to prevent and control the landslide. Long-term monitoring results showed that these methods had a high rectification effect and successfully controlled landslide deformation and displacement.

The prevalence of isolated systolic hypertension (ISH) has doubled between 2002−2005 and 2014 among the oldest‐old population in China. However, the prevalence and characteristics of ISH among the oldest‐old population in southwestern China remain less known. This study aimed to investigate the prevalence of ISH among the oldest‐old population in Chengdu and identify associated factors to provide valuable information for disease etiology and prevention. We recruited 1,312 participants aged over 80 years by using a stratified cluster sampling method between September 2015 and June 2016, from three districts (Jinjiang, Qingyang, and Longquanyi) of Chengdu, the largest city of southwest China. A structured questionnaire, anthropometric data, and blood pressure were collected according to the standard method. Blood pressure was measured three times by using a standardized mercury sphygmomanometer after a 10‐minute seated rest. Of 1312 participants, 53.0% (n = 695) had ISH. The prevalence of ISH in men and women was 54.7% and 51.3%, respectively, with no significant sex difference (P =.222). The prevalence of ISH increased with advanced age in men (P for trend = 0.029), 52.5% for the 80−84 years group, 55.2% for the 85−89 years group, and 70.4% for the 90–98 years group, respectively. Multivariable logistic regression analyses found that drinking (OR = 1.85, 95%CI = 1.26−2.71), being overweight (OR = 1.88, 95%CI = 1.19−2.96), and having a higher heart rate (OR = 0.66, 95%CI = 0.51−0.86) were associated with ISH. Stratified by sex, these three factors remained significant in men. Our work highlights that the burden of ISH is substantial among the oldest‐old population in southwestern China. [ABSTRACT FROM AUTHOR]

Automatic grading method of pomelo fruit according to the shape and size is urgently needed in the industry since the work mainly depends on artificial judgment currently. In this research, a method, which detected the vertical and horizontal size of pomelo by using contour coordinate transformation fitting, fruit shape feature extraction and direction angle compensation algorithm, while it determined the shape defects based on fruit shape index, was proposed. The image acquisition system was self-designed and built up with a CMOS camera, a dot matrix LED light source, a plane mirror, the computer, a box and brackets. The image data containing whole surface information of Shatian pomelo samples with different sizes and shapes were collected by this system. The G-B component grayscale image was chosen for denoising and segmentation. The Laplacian edge detection algorithm was implemented to extract the edge pixels of the fruit. The polynomial fitting method was applied to converse the rectangular coordinates to polar coordinates so that the fruit shape description was simplified. The characteristic point polar angle value was used to compensate the random direction of the vertical and horizontal diameters of the sample. Then the vertical and horizontal diameters of fruit were calculated after classifying the sample shapes into the spherical and the pear-like categories. For the involved 168 pomelo samples, the average error, maximum absolute error and average relative error of the vertical diameters were 2.23 mm, 7.39 mm and 1.6% respectively, while these parameters of the horizontal diameters were 2.21 mm, 7.66 mm and 1.4% respectively. The fruit shape discriminant model was established by using BP neural network algorithm based on the seven features extracted from the fitting function and verified by independent validation set including 3 peak heights, 3 peak widths and 1 trough value difference. The total recognition rate of shape identification was 83.7%. The results illustrated that the method had the potential to measuring the pomelo size and shape for grading fast and non-destructively.

Vegetation plays a crucial role in nature, with intricate interactions between it and the geographical environment. The Yangtze River Basin (YRB) refers to the third largest river basin globally and an essential ecological security barrier in China. Monitoring vegetation dynamics in the basin is of profound significance for addressing climate change, soil erosion, and biodiversity loss in the basin's ecosystems. Here, we investigate the spatiotemporal variations of vegetation at both the basin and land cover scales in the YRB from 2000 to 2020. We elucidate the determinants driving the changes and explore future normalized difference vegetation index (NDVI) trends. The results indicate that NDVI in the YRB increased at a rate of 0.0032 year−1 (p < 0.01) over the past 21 years, and it is anticipated to maintain an upward trend in the future. Regions in the upper and middle reaches of the YRB demonstrated higher NDVI, whereas regions in the headwater area and the lower reaches showed lower NDVI. Significant vegetation improvement was primarily concentrated in the central part of the basin, while noticeable vegetation degradation was observed in the eastern region. Temperature and wind speed were identified as the primary controlling factors affecting vegetation greenness. Global‐scale climate oscillations played a significant role in driving periodic variations in NDVI, with La Niña events tending to increase NDVI, while El Niño events hindered its rise. Land cover types were influenced by long‐term interactions between natural factors and human activities, although short‐term vegetation variations might be more affected by the latter. Our findings provide valuable insights into the mechanisms behind vegetation variability driven by multiple variables, and the strong vegetation carbon sink capacity advances the conservation and development of ecosystems. [ABSTRACT FROM AUTHOR]