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Monitoring the coastline dynamic can provide the basis for the balance of sediment erosion and deposition. The evaluation of coastal stability is beneficial to decision makers for the rational development and ecological conservation of coastal resources. The present study first collected 61 scenes of remote sensing images and extracted the multi-temporal coastlines from the years 1990–2020 in Jiangsu Province, China using an improved waterline method. Given the characteristics of gentle slopes of our study area, we modified the coastlines using actual tidal level data to avoid the influence from different tidal regimes. Finally, the coastal stability analysis was conducted on the central coast of Jiangsu, which experiences frequent changes in erosion and siltation. The results showed that the coastline has changed significantly; the natural coastline decreased by 116 km, while the artificial coastline increased by 108 km. the area of tidal flats decreased by 1152 km2, and the average width of the tidal flats decreased from 8.83 km to 3.55 km. In general, the coastline advanced seawards for many years, mainly due to sediment siltation and tidal flat reclamation, with annual average rates of siltation and reclamation of 9.67 km/a and 40.75 km/a, respectively. The node of siltation and erosion migrated 1.8 km southwards, moving from the Sheyang Estuary to the Doulong Port. The coastal stability gradually decreased from north to south, by values of 88.5 km (40%) for stable coast and 63.97 km (28.9%) for extremely unstable coast. The most unstable coast came from frequent reclamation areas. The method in this study is expected to provide a reference for evaluating the stability of typical muddy coasts, and our results can provide a basis for the sustainable development, utilization, and protection of coastal areas.

Widespread mortality of eastern hemlock (Tsuga canadensis [L.] Carr.) has been occurring due to the introduction of hemlock woolly adelgid (Adelges tsugae Annand) (HWA), threatening millions of hectares of hemlock-dominated forests in the eastern United States. HWA feeds at the base of needles and removes stored carbohydrates, which can impact leaf-level physiology, contributing to the decline of the tree. However, these physiological mechanisms in HWA-infested hemlocks are still not clearly understood. We investigated hemlock leaf physiology year-round at three forested sites with various degrees of infestation. At each site, half the trees were treated with imidacloprid (Merit® 2 F, Bayer, Kansas City, MO, USA) while the rest were left untreated. Imidacloprid is widely used to control HWA but can itself have phytotoxic effects. After one growing season, there was an increase in photosynthetic rates (7.5%, p = 0.0163) and stomatal conductance (7.1%, p = 0.0163) across sites in the trees treated with imidacloprid. After two years, the imidacloprid treatment also increased bud break from 22.5% to 88.7% at Fishburn (the most severely impacted site) and from 22.7% to 58.9% at Mountain Lake (the least impacted site), and slightly increased chlorophyll fluorescence for treated trees at Fishburn. Chemical treatment also slightly increased water use efficiency at Mountain Lake. These results suggest that HWA is causing tree mortality largely through a reduction in leaf area caused by decreasing bud break and also by a slight, but significant, reduction in leaf-level photosynthesis and stomatal conductance. Published version

Ultrasound contrast enhanced imaging has seen widespread uptake in research and clinical diagnostic imaging. This includes applications such as vector flow imaging, functional ultrasound and super-resolution Ultrasound Localization Microscopy (ULM). All of these require testing and validation during development of new algorithms with ground truth data. In this work we present a comprehensive simulation platform BUbble Flow Field (BUFF) that generates contrast enhanced ultrasound images in vascular tree geometries with realistic flow characteristics and validation algorithms for ULM. BUFF allows complex micro-vascular network generation of random and user-defined vascular networks. Blood flow is simulated with a fast Computational Fluid Dynamics (CFD) solver and allows arbitrary input and output positions and custom pressures. The acoustic field simulation is combined with non-linear Microbubble (MB) dynamics and simulates a range of point spread functions based on user-defined MB characteristics. The validation combines both binary and quantitative metrics. BFF's capacity to generate and validate user-defined networks is demonstrated through its implementation in the Ultrasound Localisation and TRacking Algorithms for Super Resolution (ULTRA-SR) Challenge at the International Ultrasonics Symposium (IUS) 2022 of the Institute of Electrical and Electronics Engineers (IEEE). The ability to produce ULM images, and the availability of a ground truth in localisation and tracking enables objective and quantitative evaluation of the large number of localisation and tracking algorithms developed in the field. BUFF can also benefit deep learning based methods by automatically generating datasets for training. BUFF is a fully comprehensive simulation platform for testing and validation of novel ULM techniques and is open source., 10 Pages, 9 Figures

The complexity of the sea background and its inestimable characteristics poses a great challenge to continuous sea target tracking. In addition, the sea targets are affected by sea waves so that they are easily blocked. The KCF algorithm is used to track the sea target. However, the KCF algorithm is not sensitive to target occlusion and target scale changes. In view of the shortcomings of the KCF algorithm, optimization of the KCF algorithm was proposed. A judgment mechanism is added to the KCF algorithm to set the confidence value. The confidence value is calculated to determine whether the target candidate sample is available. The confidence value is calculated to judge whether the target candidate sample is available or not. If it is available, the tracking will continue. Otherwise, the reference sample will be used instead of the candidate sample to continue tracking. Through this mechanism to improve the defect of KCF algorithm insensitive to target occlusion. So as to achieve the goal of stable tracking of sea targets.

To decrease dependency of fossil fuels and avoid direct competition with food crops, massive research efforts are investigating next-generation cellulose biofuel crops such as switchgrass (Panicum virgatum). A low-input, sustainable switchgrass production could be achieved by reducing traditional management practices though applying plant growth promoting rhizobacteria (PGPR), of which our understanding is still rather limited. To elucidate physiological mechanisms behind PGPR's beneficial effects, we inoculated switchgrass seedlings with Burkholderia phytofirmans strain PsJN. Two experiments were conducted to determine the initial and long-term responses of switchgrass to PsJN inoculation by tracking growth and leaf physiology. In a third experiments, we tested the effects of PsJN on growth and leaf-level physiology of switchgrass under a moderate pre-drought conditioning and a successive severe drought stress. PsJN inoculation increased biomass and promoted elongation of shoots within 17 days following inoculation. The enhanced root growth in PsJN inoculated plants lagged behind the shoot response, resulting in greater allocation to aboveground growth (p=0.0041). Lower specific root length (p=0.0158) and higher specific leaf weight (p=0.0029) were also observed in PsJN inoculated seedlings, indicating advanced development. Photosynthetic rates (Ps) were higher in PsJN inoculated seedlings after 17 days (54%, p=0.0016), which were related to higher stomatal conductance, greater water use efficiency, and lower non-stomatal limitation of Ps. These rapid changes in leaf physiology are at least partially responsible for switchgrass growth enhancement from PsJN treatment. The early growth enhancement in PsJN inoculated switchgrass linearly decreased with plant age. PsJN inoculation increased Ps of upper canopy leaves by 13.6% but reduced Ps of lower canopy leaves by 8.2%. Accelerated leaf senescence and early flowering were observed in PsJN-inoculated switchgrass, which might contribute to slightly lower aboveground biomass at final harvesting. Drought preconditioning increased Ps of PsJN-inoculated switchgrass during a later severe drought; whereas, control switchgrass only benefited from drought preconditioning when leaf water potential dropped below -1 MPa. This study verified early growth enhancement and accelerated development of switchgrass due to PsJN inoculation. Rapid improvement in leaf physiology is related to enhanced productivity. PsJN inoculation also improve drought tolerance of switchgrass. Ph. D.