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Abstract Land Use/Cover Change (LUCC) plays a crucial role in sustainable land management and regional planning. However, contemporary feature extraction approaches often prove inefficient at capturing critical data features, thereby complicating land cover categorization. In this research, we introduce a new feature extraction algorithm alongside a Segmented and Stratified Principal Component Analysis (SS-PCA) dimensionality reduction method based on correlation grouping. These methods are applied to UAV LiDAR and UAV HSI data collected from land use types (e.g., residential areas, agricultural lands) and specific species (e.g., tree species) in urban, agricultural, and natural environments to reflect the diversity of the study area and to demonstrate the ability of our methods to be applied in different classification scenarios. We utilize LiDAR and HSI data to extract 157 features, including intensity, height, Normalized Digital Surface Model (nDSM), spectral, texture, and index features, to identify the optimal feature subset. Subsequently, the best feature subset is inputted into a random forest classifier to classify the features. Our findings demonstrate that the SS-PCA method successfully enhances downscaled feature bands, reduces hyperspectral data noise, and improves classification accuracy (Overall Accuracy = 91.17%). Additionally, the CFW method effectively screens appropriate features, thereby increasing classification accuracy for LiDAR (Overall Accuracy = 78.10%), HIS (Overall Accuracy = 89.87%), and LiDAR + HIS (Overall Accuracy = 97.17%) data across various areas. Moreover, the integration of LiDAR and HSI data holds promise for significantly improving ground fine classification accuracy while mitigating issues such as the ‘salt and pepper noise’. Furthermore, among individual features, the LiDAR intensity feature emerges as critical for enhancing classification accuracy, while among single-class features, the HSI feature proves most influential in improving classification accuracy.

In the realm of remote sensing, the vegetation index (VI) can bring out the subtleties and characteristics of a class of features or a specific feature and can indicate crop development, vegetation and non-vegetation, soil, and other related information. However, in the plateau region, due to characteristics such as plant type, soil type, and vegetation density, the currently available vegetation indices cannot properly extract vegetation information. Therefore, this study proposes a visible light vegetation index based on the visible band, the Improved-Red-Green-Blue Vegetation Index (IRGBVI), by analyzing the spectral characteristics of seven species of landforms in the visible light bands of the UAV in the plateau region, and applies this VI to compare the accuracy of vegetation information extraction with that of 13 VIs based on visible light bands. The investigation demonstrates that IRGBVI can successfully extract plant information with high accuracy in different regions of the plateau and can effectively eliminate the impacts of blue roofs and other factors in images. In conclusion, IRGBVI is a novel visible light vegetation index ideal for extracting vegetation information in plateau regions, and it has strong generalizability and reliability.

Abstract Aim The purpose of this study was to investigate the association between the metabolic score for insulin resistance (METS-IR) and bone mineral density (BMD) in American non-diabetic adults. Methods We conducted a cross-sectional study with 1114 non-diabetic adults from the National Health and Nutrition Examination Survey cycle (2013–2014). The associations between METS-IR and BMD of total femur and spine were assessed by the multiple linear regression and verified the non-linear relationship with a smooth curve fit and threshold effect model. Furthermore, we evaluated the relationship between METS-IR, FRAX score, and history of bone fractures. Results We found that BMD of the total femur and spine increased by 0.005 g/cm3 and 0.005 g/cm3, respectively, for a one-unit increase of METS-IR in all participants. This positive association was more pronounced among higher METS-IR participants, and there was a non-linear relationship, which was more significant when the MTTS-IRfemur was

Objective: We examined the relationships between infants’ growth trajectories and prenatal exposure to air pollution, which is still under-investigated. Methods: A birth cohort study was constructed using medical records of pregnant women and infants born between 2015 and 2019 in Foshan, China. Using satellite-based spatial-temporal models, prenatal exposure to air pollutants including particulate matter with an aerodynamic dimension of < 2.5 µm (PM2.5), sulfur dioxide (SO2), nitrogen dioxide (NO2), and ozone (O3) was assessed at each woman's residence. Latent class growth modeling was used to identify trajectories of physical (body length and weight) growth and neurodevelopment, which were repeatedly measured within 1 year after birth. Logistic regression models were used to investigate the associations between prenatal exposure to air pollution and the risks of growth disorders, adjusting for an array of potential confounders. Results: We identified two growth trajectories for body length [normal: 3829 (93%); retardation: 288 (7%)], three for weight [normal: 2475 (59.6%); retardation: 390 (9.4%); overgrowth: 1287 (31%)], and two for neurodevelopment [normal: 956 (66.1%); retardation: 491 (33.9%)]. For exposure over whole pregnancy, SO2 was associated with an increased risk of body length retardation (OR for per 1 µg/m3 increment: 1.09, 95%CI: 1.01–1.17); PM2.5 (OR: 1.05, 95%CI: 1.03–1.07), SO2 (OR: 1.15, 95%CI: 1.08–1.22), and NO2 (OR: 1.05, 95%CI: 1.03–1.07) were positively associated with neurodevelopmental retardation. Such associations appeared stronger for exposures over the first and second trimesters. No significant associations were detected for weight growth. Conclusions: Maternal exposure to air pollution during pregnancy was associated with higher risks of impairments in both physical growth, particularly body length, and neurodevelopment.

Along the southeastern margin of the Tibetan Plateau, an important boundary fault, known as the Red River Fault (RRF), formed during the extrusion of mantle and lower crustal materials beneath the Tibetan Plateau. The characteristics of RRF activity are important for understanding the tectonic evolution of the southeastern margin of the Tibetan Plateau. There is less knowledge about the strong earthquake recurrence interval in the southern segment of the RRF than about its northern segment. In this study, based on the characteristics of the active tectonic landform, three paleoseismic trenches were excavated in Adipo Village north of Honghe County in the southern segment of the RRF. In these trenches, three paleoseismic events that occurred in the middle and late Holocene were identified. According to the 14C dating results, these events were constrained to 785–504 BC, 26–492 AD, and 1,415–1857 AD. The average earthquake recurrence interval was determined to be approximately 960–1,320 a.

Abstract To investigate the relationship between serum high-density lipoprotein (HDL-C) and spinal bone mineral density (BMD) under different serum 25-hydroxyvitamin D (25 (OH) D) levels in adults over 40 years old and to explore its mechanism. We include participants over the age of 40 with data on HDL-C, 25 (OH) D, spinal BMD, and other variables in the National Health and Nutrition Examination Survey 2007–2010 in the analysis. A weighted multiple linear regression model was used to evaluate the association between serum HDL-C and spinal BMD in different gender, ages, and serum 25 (OH) D levels. A total of 3599 subjects aged ≥ 40 years old were included in this study. Univariate analysis of the complete correction model showed a negative correlation between serum HDL-C and spinal BMD. In the two subgroups of serum 25 (OH) D, we found that the higher the serum HDL-C in the female with serum 25 (OH) D

IntroductionTo compare the accuracy of Artificial Intelligent Breast Ultrasound (AIBUS) with hand-held breast ultrasound (HHUS) in asymptomatic women and to offer recommendations for screening in regions with limited medical resources.Methods852 participants who underwent both HHUS and AIBUS were enrolled between December 2020 and June 2021. Two radiologists, who were unaware of the HHUS results, reviewed the AIBUS data and scored the image quality on a separate workstation. Breast imaging reporting and data system (BI-RADS) final recall assessment, breast density category, quantified lesion features, and examination time were evaluated for both devices. The statistical analysis included McNemar’s test, paired t-test, and Wilcoxon test. The kappa coefficient and consistency rate were calculated in different subgroups.ResultsSubjective satisfaction with AIBUS image quality reached 70%. Moderate agreements were found between AIBUS with good quality images and HHUS for the BI-RADS final recall assessment (κ = 0.47, consistency rate = 73.9%) and breast density category (κ = 0.50, consistency rate = 74.8%). The lesions measured by AIBUS were statistically smaller and deeper than those measured by HHUS (P < 0.001), though they were not significant in clinical diagnosis (all < 3 mm). The total time required for the AIBUS examination and image interpretation was 1.03 (95% CI (0.57, 1.50)) minutes shorter than that of HHUS per case.ConclusionModerate agreement was obtained for the description of the BI-RADS final recall assessment and breast density category. With image quality comparable to that of HHUS, AIBUS was superior for the efficiency of primary screening.

Evolution in digital technology is bringing improvements in the lifestyle and behaviors of ordinary people throughout the world. In recent years, research is undertaken to investigate the penetration of web-based sports applications in students' recreational activities. This study uses a systematic thematic analysis to analyze the literature on the research topic. We perform a rigorous thematic analysis on the qualitative information from ten chosen studies, following the particular data analysis model with five steps: compilation, disassembling, reassembling, interpreting, and concluding. This study's results show that technology-based motivation among students is widely explored in the literature. The exercise environment and behavioral diversity are other identified codes (data units) in the chosen literature. This study finds that the use of technology can effectively promote higher participation of students in low-intensity exercises.

In order to quantitatively obtain the characteristic parameters of complex geomorphological structures, high precision and high resolution topographic and geomorphological data are required.In the detection of complex geomorphic features, UAV aerial survey combined with imaging point cloud can accomplish the task of spatial detection of complex geomorphic features quickly, efficiently, safely and accurately.In this study, the UAV measurement technology is used to obtain high-resolution geomorphological image data, construct a realistic 3D scene model and analyse the geomorphological features of the typical local scenes of the ring-shaped landform at the southern edge of Lufeng Dinosaur Valley.The experimental results show that: ①The DSM data obtained based on the UAV imaging point cloud can accurately express the real geomorphological features of the study area by filtering, extracting thinning, classifying and other data processing to obtain the ground points and constructing 0.2 m resolution DEM data by using the progressive encrypted triangle network method.②By constructing 7 typical elevation profiles of the circular scene "inner-middle-outer", the comparative analysis confirms that the topography of the study area is characterized by the 0 profile line as the main highland ridgeline, showing a circular "basin rim" pattern, with gradually decreasing elevation on the inner and outer sides, and the elevation of the outer profile of the "basin rim" changes dramatically, and the topography is more complex than that of the inner landscape.③In order to further detect and extract the information of micro-morphological features, the accurate DEM data constructed by the principle of UAV imaging combined with the realistic 3D model of the survey area, quantitatively extracted the slope, slop direction, relative height difference, contour, ridge line valley line and other related parameters of the area for accurate quantitative measurement and analysis and discussion.④ Using the multi-view visual interpretation of the three-dimensional 3D model and the analysis of typical scenes, micro-geomorphic features such as the development of washouts in the survey area and the nodal laminated surface of the geological body can be clearly identified.Through the above experimental research on geomorphological 3D scene detection, it is easy to find that the use of realistic 3D models can quickly and accurately present the geomorphological features of the survey area, and the comprehensive analysis of imaging point cloud data can quantitatively and semi-quantitatively reveal regional geological structure information.Overall, the UAV measurement technology and imaging point cloud 3D product application in geological survey has practical significance and unique technical advantages.

ObjectiveThe aim of this study was to evaluate the effectiveness and safety of rescue therapy, a therapy in which rescue devices such as balloon angioplasty, Apollo stent, Wingspan stent, Solitaire stent, or other self-expanding stents are used after the failure of mechanical thrombectomy (MT) and to determine the most effective rescue measure for acute basilar artery occlusion (BAO) after the failure of MT.MethodsFor this study, we recruited patients from the BASILAR registry. All participants were divided into three groups: the recanalized with rescue therapy group, the recanalized without rescue therapy group, and the non-recanalized group. Clinical outcomes at 90 days and 1 year were compared. The association of rescue measures with favorable outcomes (modified Rankin Scale [mRS] score of 0–3) in patients achieving successful recanalization via rescue therapy was estimated using multivariate logistic regression analyses.ResultsAmong the participants, recanalization failure was found in 112 patients and successful recanalization in 473 patients, with 218 patients receiving rescue therapy and 255 patients without rescue therapy. Of these, 111 (43.5%) patients in the recanalized without rescue therapy group, 65 (29.8%) patients in the recanalized with rescue therapy group, and nine (8.0%) patients in the non-recanalized group achieved favorable outcomes at 90 days. Both the recanalization with rescue therapy and the recanalization without rescue therapy groups were associated with favorable outcomes at 90 days and 1 year compared with the non-recanalized group. Moreover, in patients receiving rescue therapy, Wingspan stents, Apollo stents, and balloon angioplasty were associated with higher rates of favorable outcomes at 90 days and 1 year than Solitaire stents.ConclusionWhether rescue therapy is administered or not, recanalization leads to favorable outcomes in patients with acute BAO. For acute BAO after MT failure, balloon angioplasty, Wingspan stenting, and Apollo stenting could be considered effective and safe rescue options but not Solitaire stenting.

Background and purposeIschemic stroke is related to inflammation. We investigated leukocyte counts, neutrophil counts, and NLR (neutrophil-to-lymphocyte ratio) to explore their prognostic potential and determine if high neutrophil counts before endovascular treatment (EVT) in patients with acute basilar artery occlusion (BAO) are associated with worse outcomes at 90 days post-EVT.MethodsLeukocyte and neutrophil counts and NLR were determined in eligible patients from the Acute Basilar Artery Occlusion Study (BASILAR). Patients were divided into four groups according to leukocyte and neutrophil counts and NLR quartiles. The primary outcome was a favorable outcome based on the modified Rankin Scale (mRS: 0–3). The secondary outcome was functional independence (mRS 0–2). The safety outcome was mortality, and an unfavorable outcome was mRS 4–6. Successful reperfusion was mTICI (modified Thrombolysis in Cerebral Infarction) of 2b or 3. All the data were collected within 90 days after EVT.ResultsWe enrolled 586 patients in the study. The leukocyte and neutrophil counts and NLR were significantly associated with clinical outcomes in all patients though no effects were seen in some intervals. Of these three parameters, the neutrophil count had the most significant impact, negatively affecting the outcome. The findings were similar in patients who were successfully recanalized.ConclusionHigher neutrophil counts predicted worse clinical outcomes 90 days after EVT. This finding supports the deleterious role of inflammation in patients with acute BAO despite EVT or successful recanalization.

IntroductionAccording to the literature on anterior circulation, comorbid atrial fibrillation (AF) is not associated with a worse functional outcome, lower reperfusion rates, or higher rates of intracranial hemorrhage after mechanical thrombectomy (MT) compared to intravenous thrombolysis (IVT) or treatment with supportive care. However, data are limited for the effect of comorbid AF on procedural and clinical outcomes of acute basilar artery occlusion (ABAO) after MT. This study aimed to investigate the effect of atrial fibrillation on outcomes after MT and long-term ischemic recurrence in patients with ABAO.MethodsWe performed a registered study of the Endovascular Treatment for Acute Basilar Artery Occlusion Study (BASILAR, which is registered in the Chinese Clinical Trial Registry, http://www.chictr.org.cn; ChiCTR1800014759) from January 2014 to May 2019, which included 647 patients who underwent MT for ABAO, 136 of whom had comorbid AF. Prospectively defined baseline characteristics, procedural outcomes, and clinical outcomes were reported and compared.ResultsOn multivariate analysis, AF predicted a shorter puncture-to-recanalization time, higher first-pass effect rate, and lower incidence of angioplasty and/or stenting (p < 0.01). AF had no effect on intracranial hemorrhage incidence [adjusted odds ratio (aOR), 1.093; 95% confidence interval (CI), 0.451–2.652], 90-day functional outcomes (adjusted common odds ratio, 0.915; 95% CI, 0.588–1.424), or mortality (aOR, 0.851; 95% CI, 0.491–1.475) after MT. The main findings were robust in the subgroup and 1-year follow-up analyses. Comorbid AF was the remaining predictor of ischemic recurrence (aOR, 4.076; 95% CI, 1.137–14.612).ConclusionsThe study revealed no significant difference in the safety and efficacy of MT for ABAO regardless of whether patients had comorbid AF. However, a higher proportion of patients with AF experienced ischemic recurrence within 1 year after MT.

Abstract Electrical transport of both longitudinal and transverse directions carries rich information. Mobility spectrum analysis (MSA) is capable of extracting charge information from conductivity tensor, including charge types, concentration and mobilities. Using a numerical method based on maximum entropy principle, i.e., maximum entropy mobility spectrum analysis (MEMSA), mobility spectrum for $$\beta $$ β -type PtBi $$_2$$ 2 is studied. Three hole-pockets and two electron-pockets were found, including a small hole pocket with very high mobility, which is very likely corresponding to Dirac Fermions. Benefiting from our high resolution result, we studied temperature dependence of carrier properties and explained the sign change phenomenon of Hall conductivity. We further compared the results with band structure obtained by our first principle calculation. The present results prove MEMSA is a useful tool of extracting carries’ information in recently discovered Iron-based superconductors, and topological materials.

As UAV technology has been leaping forward, small consumer-grade UAVs equipped with optical sensors are capable of easily acquiring high-resolution images, which show bright prospects in a wide variety of terrains and different fields. First, the crater rim landscape of the Dinosaur Valley ring formation located on the central Yunnan Plateau served as the object of the surface change detection experiment, and two repetitive UAV ground observations of the study area were performed at the same altitude of 180 m with DJI Phantom 4 RTK in the rainy season (P1) and the dry season (P2). Subsequently, the UAV-SfM digital three-dimensional (3D) modeling method was adopted to build digital models of the study area at two points in time, which comprised the Digital Surface Model (DSM), Digital Orthomosaic Model (DOM), and Dense Image Matching (DIM) point cloud. Lastly, a quantitative analysis of the surface changes at the pit edge was performed using the point-surface-body surface morphological characterization method based on the digital model. As indicated by the results, (1) the elevation detection of the corresponding check points of the two DSM periods yielded a maximum positive difference of 0.2650 m and a maximum negative value of −0.2279 m in the first period, as well as a maximum positive difference of 0.2470 m and a maximum negative value of −0.2589 m in the second period. (2) In the change detection of the two DOM periods, the vegetation was 9.99% higher in the wet season than in the dry season in terms of coverage, whereas the bare soil was 10.54% more covered than the wet season. (3) In general, the M3C2-PM distances of the P1 point cloud and the P2 point cloud were concentrated in the interval (−0.2,0.2), whereas the percentage of the interval (−0.1,0) accounted for 26.69% of all intervals. The numerical model of UAV-SfM was employed for comprehensive change detection analysis. As revealed by the result of the point elevation difference in the constant area, the technique can conform to the requirements of earth observation with certain accuracy. The change area suggested that the test area can be affected by natural conditions to a certain extent, such that the multi-source data can be integrated to conduct more comprehensive detection analysis.

BackgroundThis study aimed to investigate the association between the hyperdense basilar artery sign (HBAS) on non-enhanced computed tomography (CT) and clinical outcomes in patients with acute basilar artery occlusion (BAO) who underwent endovascular treatment (EVT).MethodsEligible patients who underwent EVT due to acute BAO between January 2014 and May 2019 were divided into two groups based on HBAS. HBAS was assessed by two neuroradiologists using five grades on nonenhanced CT. The primary outcome was a favorable functional outcome (defined as a modified Rankin Scale [mRS] of 0–3) at 90 days. Secondary outcomes included successful recanalization and mortality within 90 days.ResultsAmong 829 patients with BAO as assessed with CT angiography, magnetic resonance angiography, or digital subtraction angiography, 643 patients were treated with EVT. Of these, 51.32% (330/643) had HBAS. Patients with HBAS were older and had more severe neurological deficits and a higher frequency of atrial fibrillation than those without HBAS. There was no significant difference in favorable outcome (adjusted odds ratio [aOR]: 1.354, 95% confidence interval [CI]: 0.906–2.024; p = 0.14), successful recanalization (aOR: 0.926, 95% CI: 0.616-−1.393; p = 0.71), and mortality (aOR: 1.193, 95% CI: 0.839–1.695; p = 0.33) between patients with or without HBAS. Subgroup analysis showed that the HBAS predicted a favorable outcome in patients aged

The ability to control magnetic coupling in graphene nanomaterials remains elusive. Here, the authors report an approach of engineering magnetic ground states in open-shell bipartite/nonbipartite nanographenes where the magnetic coupling sign between two spins are controlled via breaking bipartite lattice symmetry.

Abstract Obtaining horizontal edges and the buried depths of geological bodies, using potential field tensor data directly is an outstanding question. The largest eigenvalue of the structure tensor is one of the commonly used edge detectors for delineating the horizontal edges without depth information of the potential field tensor data. In this study, we presented a normalized largest eigenvalue of structure tensor method based on the normalized downward continuation (NDC) to invert the source location parameters without any priori information. To improve the stability and accuracy of the NDC calculation, the Chebyshev–Pade´ approximation downward continuation method was introduced to obtain the potential field data on different depth levels. The new approach was tested on various models data with and without noise, which validated that it can simultaneously obtain the horizontal edges and the buried depths of the geological bodies. The satisfactory results demonstrated that the normalized largest eigenvalue of structure tensor can describe the locations of geological sources and decrease the noise interference magnified by the downward continuation. Finally, the method was applied to the gravity data over the Humble salt dome in USA, and the near-bottom magnetic data over the Southwest Indian Ridge. The results show a good correspondence to the results of previous work.

Ionic substitution is a useful way to manipulate structural, electronic, magnetic phase transitions in strongly correlated materials. Here, the authors report electric-field controlled protonation in SrRuO3, resulting in a large structural expansion and a ferromagnetic-to-paramagnetic phase transition.

Unmanned aerial vehicles (UAVs) and light detection and ranging (LiDAR) can be used to analyze the geomorphic features in complex plateau mountains. Accordingly, a UAV–LiDAR system was adopted in this study to acquire images and lidar point-cloud dataset in the annular structure of Lufeng, Yunnan. A three-dimensional (3D) model was constructed based on structure from motion and multi-view stereo (SfM–MVS) in combination with a high-resolution digital elevation model (DEM). Geomorphic identification, measurement, and analysis were conducted using integrated visual interpretation, DEM visualization, and geographic information system (GIS) topographic feature extraction. The results indicated that the 3D geomorphological visualization and mapping were based on DEM, which was employed to identify the dividing lines and ridges that were delineated of the pit rim structure. The high-resolution DEM retained more geomorphic detail information, and the topography and the variation between ridges were analyzed in depth. The catchment and ponding areas were analyzed using accurate morphological parameters through a multi-angle 3D visualization. The slope, aspect, and topographic wetness index (TWI) parameters were analyzed through mathematical statistics to qualitatively and accurately analyze the differences between different ridges. This study highlighted the significance of the UAV–LiDAR high-resolution topographic measurements and the SfM–MVS 3D scene modelling in accurately identifying geomorphological features and conducting refined analysis. An effective framework was established to acquire high-precision topographic datasets and to analyze geomorphological features in complex mountain areas, which was beneficial in deepening the research on numerical simulation analysis of geomorphological features and reveal the process evolution mechanism.

Background and Purpose: It is unknown the benefit of endovascular therapy (EVT) for progressive stroke in patients with basilar artery occlusion (BAO). The aim of this study was to compare the efficacy and safety of EVT with standard medical therapy (SMT) in a population of BAO patients with progressive stroke.Methods: The EVT for Acute Basilar Artery Occlusion Study (BASILAR) is a national prospective registry of consecutive patients with acute BAO within 24 h of symptom onset. According to the applied therapy, all patients were divided into SMT and EVT groups. Subsequently, the EVT group was divided into early (≤6 h) and late groups (>6 h) according to the time window. The efficacy outcome was favorable functional outcomes (modified Rankin Scale score ≤ 3) at 90 days. The safety outcomes included mortality within 90 days and symptomatic intracerebral hemorrhage (sICH) after EVT.Results: The EVT cohort presented more frequently with a favorable functional outcome (adjusted odds ratio, 5.49; 95% confidence interval, 2.06–14.61, p = 0.01) and with a decreased mortality (adjusted odds ratio, 0.3; 95% confidence interval, 0.17–0.54, p < 0.001). What's more, EVT still safe (P = 0.584, P = 0.492, respectively) and effective (P = 0.05) in patients with progressive stroke when the treatment time window exceeds 6 h.Conclusions: EVT was more effective and safer than SMT for progressive stroke in patients with BAO. Besides, EVT remains safe and effective in patients with progressive stroke when the treatment time window exceeds 6 h. Predictors of desirable outcome in progressive stroke patients undergoing EVT included lower baseline NIHSS score, higher baseline pc-ASPECTs, successful recanalization and shorter puncture to recanalization time.

In the field of path tracking control for wheeled mobile robots, researchers generally believe that the motion of robots meets non-holonomic constraints. However, the robot may sideslip by centrifugal force when it is steering. This kind of slip is usually uncontrollable and dangerous. In order to prevent sideslip and improve the performance of path tracking control, we propose a controller based on tire mechanics. Moreover, the new controller is based on the model predictive control, and this control method has proven to be suitable for path tracking of wheeled mobile robots. The proposed controller was verified by simulation and compared with a model predictive controller based on kinematics (non-holonomic constraints). As for the simulation results, the maximum values of displacement error, heading error, lateral velocity, and slip angle of the dynamic-based model predictive controller are 0.2086 m, 0.1609 rad, 0.1546 m/s, and 0.0576 rad, respectively. Compared with the kinematics-based model predictive controller, the maximum values of the above-mentioned parameters of the dynamic-based controller reduce by 86.55%, 72.25%, 96.30%, and 90.02%, respectively. The above-mentioned results show that the proposed controller can effectively improve the accuracy of path tracking control and avoid sideslip.

This work aimed to detect the vegetation coverage and evaluate the benefits of afforestation and ecological protection. Unmanned aerial vehicle (UAV) aerial survey was adopted to obtain the images of tailings area at Ma’anshan near the Dianchi Lake estuary, so as to construct a high-resolution Digital Orthophoto Map (DOM) and high-density Dense Image Matching (DIM) point cloud. Firstly, the optimal scale was selected for segmentation by considering the terrain. Secondly, the visible-band difference vegetation index (VDVI) of the classified vegetation information of the tail mining area was determined from the index gray histogram, ground class error analysis, and the qualitative and quantitative analysis of the bimodal index. Then, the vegetation information was extracted by combining the random forest (RF) classification algorithm. Finally, the extracted two-dimensional (2D) vegetation information was mapped to the three-dimensional (3D) point cloud, and the redundant data was eliminated. Fractional vegetation cover (FVC) was counted in the way of surface to point and human–machine combination. The experimental results showed that the vegetation information extracted from the 2D image was mapped to the 3D point cloud in the form of surface to point, and the redundant bare ground information was eliminated. The statistical FVC was 36.06%. The field survey suggested that the vegetation information in the turf dam area adjacent to the open phosphate deposit accumulation area research area was sparse. Relevant measures should be taken in the subsequent mining to avoid ecological damage caused by expanded phosphate mining. In general, applying UAV measurement technology and related 2D and 3D products to detect the vegetation coverage in an open phosphate mine area was of practical significance and unique technical advantages.

Background: To date, few data have been reported on clinical outcomes following interventions in elderly populations with acute basilar artery occlusion. Using data from the Endovascular Treatment for Acute Basilar Artery Occlusion Study (BASILAR), we evaluated the efficacy and safety of intervention and determined predictors of outcomes among elderly patients in China. Methods: Patients from January 2014 to May 2019 were dichotomized into elderly (75 years or older) and nonelderly patients (under 75 years). Pearson’s Chi-square test and multivariate logistic regression were performed to assess 90-day favorable functional outcome (defined as a modified Rankin scale score of 0–3), mortality and symptomatic intracranial hemorrhage between intervention and conservative cohorts in elderly patients. Results: Among the 829 patients in the BASILAR, 182 patients aged 75 years or older were analyzed. These patients were divided into intervention (127 patients) and conservative (55 patients) cohorts. Compared with the conservative cohort, the intervention cohort presented more frequently with a favorable functional outcome (28.3% versus 12.7%; p = 0.023) and with a decreased mortality (54.3% versus 76.4%; p = 0.005). There was no difference in symptomatic intracranial hemorrhage (4.7% versus 0, p = 0.235). Multivariate analysis indicated that intervention was associated with favorable functional outcome (adjusted odds ratio, 0.262; 95% confidence interval, 0.088–0.778, p = 0.016) and lower mortality (adjusted odds ratio, 0.257; 95% confidence interval, 0.109–0.606, p = 0.002). In the intervention cohort, initial National Institutes of Health Stroke Scale (NIHSS) score and occlusion site were associated with functional outcome, and initial NIHSS score and recanalization were associated with mortality. Conclusions: Although the overall outcome following intervention was worse with age, intervention was more effective and safer than conservative treatment for elderly Chinese patients with basilar artery occlusion. Predictors of desirable outcome in elderly patients undergoing intervention included lower initial NIHSS score, occlusion site and successful recanalization. Clinical Trial Registration-URL: http://www.chictr.org . Unique identifier: ChiCTR-1800014759

Unmanned Aerial Vehicles (UAVs) are a novel technology for landform investigations, monitoring, as well as evolution analyses of long−term repeated observation. However, impacted by the sophisticated topographic environment, fluctuating terrain and incomplete field observations, significant differences have been found between 3D measurement accuracy and the Digital Surface Model (DSM). In this study, the DJI Phantom 4 RTK UAV was adopted to capture images of complex pit-rim landforms with significant elevation undulations. A repeated observation data acquisition scheme was proposed for a small amount of oblique-view imaging, while an ortho-view observation was conducted. Subsequently, the 3D scenes and DSMs were formed by employing Structure from Motion (SfM) and Multi-View Stereo (MVS) algorithms. Moreover, a comparison and 3D measurement accuracy analysis were conducted based on the internal and external precision by exploiting checkpoint and DSM of Difference (DoD) error analysis methods. As indicated by the results, the 3D scene plane for two imaging types could reach an accuracy of centimeters, whereas the elevation accuracy of the orthophoto dataset alone could only reach the decimeters (0.3049 m). However, only 6.30% of the total image number of oblique images was required to improve the elevation accuracy by one order of magnitude (0.0942 m). (2) An insignificant variation in internal accuracy was reported in oblique imaging-assisted datasets. In particular, SfM-MVS technology exhibited high reproducibility for repeated observations. By changing the number and position of oblique images, the external precision was able to increase effectively, the elevation error distribution was improved to become more concentrated and stable. Accordingly, a repeated observation method only including a few oblique images has been proposed and demonstrated in this study, which could optimize the elevation and improve the accuracy. The research results could provide practical and effective technology reference strategies for geomorphological surveys and repeated observation analyses in sophisticated mountain environments.

The evolution between Fermi-liquid and non-Fermi-liquid states in correlated electron systems has been a central subject in condensed matter physics because of the coupled intriguing magnetic and electronic states. An effective pathway to explore the nature of non-Fermi-liquid behavior is to approach its phase boundary. Here we report a crossover from non-Fermi-liquid to Fermi-liquid state in metallic CaRuO_{3} through ionic liquid gating induced protonation with electric field. This electronic transition subsequently triggers a reversible magnetic transition with the emergence of an exotic ferromagnetic state from this paramagnetic compound. Our theoretical analysis reveals that hydrogen incorporation plays a critical role in both the electronic and magnetic phase transitions via structural distortion and electron doping. These observations not only help understand the correlated magnetic and electronic transitions in perovskite ruthenate systems, but also provide novel pathways to design electronic phases in correlated materials.

Obstacle avoidance is a core part of the autonomous driving of off-road vehicles, such as semi-trailers. Due to the long length of semi-trailers, the traditional obstacle avoidance controller based on the circumcircle model can ensure that there is no collision between the semi-trailer and the obstacle, but it also greatly reduces the passable area. To solve this problem, we propose a new obstacle avoidance model. In this model, the distance between the obstacle and the middle line of semi-trailers is used as the indicator of obstacle avoidance. Based on this model, we design a new obstacle avoidance controller for semi-trailers. The simulation results show that the proposed controller can ensure that no collision occurs between the semi-trailer and the obstacle. The minimum distance between the obstacle center and the semi-trailer body trajectory is greater than the sum of the obstacle radius and the safety margin. Compared with the traditional obstacle avoidance controller based on the circumcircle model, the proposed controller greatly reduces the error between the semi-trailer and the reference path during obstacle avoidance.

At present, many path tracking controllers are unable to actively adjust the longitudinal velocity according to path information, such as the radius of the curve, to further improve tracking accuracy. For this problem, we propose a new path tracking framework based on model predictive control (MPC). This is a multilayer control system that includes three path tracking controllers with fixed velocities and a velocity decision controller. This new control method is named multilayer MPC. This new control method is compared to other control methods through simulation. In this paper, the maximum values of the displacement error and the heading error of multilayer MPC are 92.92% and 77.02%, respectively, smaller than those of nonlinear MPC. The real-time performance of multilayer MPC is very good, and parallel computation can further improve the real-time performance of this control method. In simulation results, the calculation time of multilayer MPC in each control period does not exceed 0.0130 s, which is much smaller than the control period. In addition, when the error of positioning systems is at the centimeter level, the performance of multilayer MPC is still good.

Path tracking of mining vehicles plays a significant role in reducing the working time of operators in the underground environment. Because the existing path tracking control of mining vehicles, based on model predictive control, is not very effective when the longitudinal velocity of the vehicle is above 2 m/s, we have devised a new controller based on nonlinear model predictive control. Then, we compare this new controller with the existing model predictive controller. In the results of our simulation, the tracking accuracy of our controller at the longitudinal velocity of 4 m/s is close to that of the existing model predictive controller, at the longitudinal velocity of 2 m/s. When longitudinal velocity is 4 m/s, the existing model predictive controller cannot drive the mining vehicle to track the given path, but our nonlinear model predictive controller can, and the maximum displacement error and heading error are 0.1382 m and 0.0589 rad, respectively. According to these results, we believe that this nonlinear model predictive controller can be used to improve the performance of the path tracking of mining vehicles.

The construction of topological insulator/superconductor heterostructures attracts a lot of interest because of its potential to realize artificial topological superconductors hosting Majorana fermions. By means of molecular beam epitaxy, high-quality thin films of a topological insulator, Bi _2 Se _3 , can be grown on a superconductor substrate, 2H-NbSe _2 (0001), with an atomically smooth interface. To ascertain the atomic structure of the Bi _2 Se _3 /NbSe _2 heterostructure, the initial growth stage was investigated with a scanning tunneling microscope (STM). In the growth process, we found that Bi atoms were first deposited to form a single Bi(110) bilayer, which is revealed to stand nearly freely on the NbSe _2 surface and exhibits various moiré patterns. In the formation of the first quintuple layer of Bi _2 Se _3 by co-depositing Bi and Se atoms, the Bi(110) bilayer transits to a BiSe interfacial layer, which effectively reduces the large lattice mismatch between Bi _2 Se _3 and NbSe _2 . Based on atomic-resolution STM images and first-principles calculations, a NaCl-type structural model is proposed for the BiSe interfacial layer, on which Bi _2 Se _3 thin films grow well in a layer-by-layer mode.

Objective To evaluate the non-inferiority of endovascular treatment (EVT) alone versus intravenous thrombolysis (IVT) followed by EVT and to assess its heterogeneity across prespecified subgroups. Methods We pooled data from two trials (SKIP in Japan; DEVT in China). Individual patient data were pooled to assess outcomes and heterogeneity of treatment effect. The primary outcome was functional independence (modified Rankin Scale score 0-2) at 90 days. Safety outcomes included symptomatic intracranial hemorrhage (sICH) and 90-day mortality. Results We included 438 patients (217 EVT alone; 221 combined IVT+EVT). The meta-analysis failed to demonstrate the non-inferiority of EVT alone over combined IVT+EVT in achieving 90-day functional independence (56.7% vs 51.6%; adjusted common odds ratio (cOR)=1.27, 95% CI 0.84 to 1.92, pnon-inferiority=0.06). Effect sizes favoring EVT alone were present with stroke onset to puncture time longer than 180 min (cOR=2.28, 95% CI 1.18 to 4.38, pinteraction ≤180 vs >180 min=0.02) and intracranial internal carotid artery ICA occlusions (for ICA cOR=3.04, 95% CI 1.10 to 8.43, pinteraction ICA vs MCA=0.08). The rates of sICH (6.5% vs 9.0%; cOR=0.77, 95% CI 0.37 to 1.61) and 90-day mortality (12.9% vs 13.6%; cOR=1.05, 95% CI 0.58 to 1.89) were comparable. Conclusions The cumulative data of these two recent Asian trials failed to unequivocally demonstrate the non-inferiority of EVT alone over combined IVT+EVT. However, our study suggests a potential role for more individualized decision-making. Specifically, Asian patients with stroke onset to EVT longer than 180 min, as well as those with intracranial ICA occlusions and those with atrial fibrillation might have better outcomes with EVT alone than with combined IVT+EVT. [ABSTRACT FROM AUTHOR]

Background The effects of secondary collateral compensation on outcomes remain unclear in patients with acute basilar artery occlusion (BAO) after endovascular treatment (EVT). This study aimed to evaluate the benefits of the anastomosis between the posterior inferior cerebellar artery (PICA) and the superior cerebellar artery (SCA) in BAO after EVT. Methods This cohort study was conducted using data from the Endovascular Treatment for Acute Basilar Artery Occlusion Study Registry. Patients with acute BAO and treated with EVT were included. The primary outcome was a modified Rankin Scale score of 0-2 at 90 days. Safety outcomes included symptomatic intracerebral hemorrhage (SICH) and 90-day mortality. Results Of the 646 patients included in the study, 196 (30.3%) patients had a PICA-SCA anastomosis. The PICA-SCA anastomosis was significantly associated with independent functional outcome at 90 days (67/196 (34.2%) vs 109/450 (24.2%), adjusted OR (aOR) 1.80 (95% CI 1.13 to 2.86), p=0.01) and was significantly associated with a decreased rate of SICH (40/442 (9.0%) vs 5/193 (2.6%), aOR 0.29 (95% CI 0.11 to 0.76), p=0.01). No significant difference was found between PICA-SCA anastomosis and 90-day mortality (219/450 (48.7%) vs 80/196 (40.8%), aOR 0.72 (95% CI 0.48 to 1.08), p=0.11). Subgroup analysis showed that the association between independent functional outcome and PICA-SCA anastomosis was strongest in patients with middle BAO (27/77 (35.1%) vs 22/118 (18.6%), aOR 2.64 (95% CI 1.13 to 6.15), p=0.03). Conclusions The PICA-SCA anastomosis is significantly associated with better functional outcomes in patients with acute BAO after EVT, especially in those with middle BAO. [ABSTRACT FROM AUTHOR]