Determination of the Sign of g factors for Conduction Electrons Using Time-resolved Kerr Rotation

The knowledge of electron g factor is essential for spin manipulation in the field of spintronics and quantum computing. While there exist technical difficulties in determining the sign of g factor in semiconductors by the established magneto-optical spectroscopic methods. We develop a time resolved Kerr rotation technique to precisely measure the sign and the amplitude of electron g factor in semiconductors

Identifying Significant Environmental Features Using Feature Recognition

The Department of Environmental Analysis at the Kentucky Transportation Cabinet has expressed an interest in feature-recognition capability because it may help analysts identify environmentally sensitive features in the landscape, including those relating to historic preservation, archaeology, endangered species habitat, and geology. LIDAR Analyst and Feature Analyst are a pair of geoprocessing software packages that have been developed by Textron Systems. Using this software, users can use LIDAR data to identify finely-scaled user-specified features. The software’s automated feature extraction saves time that might otherwise be spent manually analyzing images and digitizing features. This report explores the capabilities and accuracy of this software by using LIDAR data to identify sinkholes throughout a small area in Kentucky. This report also discusses an alternative LIDAR-based geoprocessing methodology developed by the Kentucky Geological Society. The method relies on ArcGIS and Python scripting to identify sinkholes. The feasibility and applicability of these methodologies are compared, the workflow for each method is outlined, and the capabilities and limitations of each are noted. Sample results—the identification of sinkholes—from each methodology are presented. The research team found the batch processing capability built into LIDAR and Feature Analyst adequate and beneficial for smaller projects, such as projects that prioritize the extraction of buildings, trees, and forest regions

Smart mitochondria-specific anchored gold-based nanosystem for integration of tumor imaging and treatment

Although recent advances have been made in improving the efficacy of photodynamic therapy, efficient therapeutic approaches based on reactive oxygen species (ROS) are needed, particularly mitochondria-specific targeting of nanomaterials that can alter the internal environment of organelles. Herein, we report the facile synthesis of mitochondria-specific anchored nano-complexes (AG-CNP) comprised of a skeleton of gold and carbon atoms for cancer therapy. Compared to the effects of gold nanoclusters (Au NCs), AG-CNP shows enhanced fluorescence imaging effects, which can be used for tumor monitoring. AG-CNP targets the mitochondria and increases ROS damage in cancer cells. After treatment with AG-CNP, the tumor inhibition rate reaches 70.94%, which is 25.98% and 36.91% higher than that of free doxorubicin (DOX) and gemcitabine (Gem), respectively. Studying the mechanism of AG-CNP inhibiting cancer shows that AG-CNP can promote tumor cells to produce excessive ROS by overexpressing P53 and increasing the number of apoptotic cancer cells, which is caused by overexpression of Caspase1 that was closely related to cell apoptosis. AG-CNP is a promising anticancer drug that targets the mitochondria in vivo to trigger excessive ROS production in tumor cells and inhibit tumor growth.X.Y., L.Z., and L.D. contributed equally to this work. This work was supported by the National Natural Science Foundation of China (21371115, 22003038, 81922037, and 11575107), the Shanghai University-Universal Medical Imaging Diagnostic Research Foundation (19H00100), Shanghai Biomedical Science and Technology Support Project (19441903600), Guangdong Basic and Applied Basic Research Foundation (Nos. 2021A1515110657 and 2022A1515010056), Shenzhen Science and Technology Program (Grant No. RCBS20210609104513023)

Design strategies of tumor-targeted delivery systems based on 2D nanomaterials

Conventional chemotherapy and radiotherapy are nonselective and nonspecific for cell killing, causing serious side effects and threatening the lives of patients. It is of great significance to develop more accurate tumor-targeting therapeutic strategies. Nanotechnology is in a leading position to provide new treatment options for cancer, and it has great potential for selective targeted therapy and controlled drug release. 2D nanomaterials (2D NMs) have broad application prospects in the field of tumor-targeted delivery systems due to their special structure-based functions and excellent optical, electrical, and thermal properties. This review emphasizes the design strategies of tumor-targeted delivery systems based on 2D NMs from three aspects: passive targeting, active targeting, and tumor-microenvironment targeting, in order to promote the rational application of 2D NMs in clinical practice.This work was supported by the Guangdong Basic and Applied Basic Research Foundation (Nos. 2021A1515110657 and 2022A1515010056), Shenzhen Science and Technology Program (Grant No. RCBS20210609104513023), National Natural Science Foundation of China (No. 81922037), and Shanghai Biomedical Science and Technology Support Project (No. 19441903600)

Hydrogeologic Investigations of Pavement Subsidence in the Cumberland Gap Tunnel

Cumberland Gap Tunnel was constructed under Cumberland Gap National Historical Park in 1996 to improve transportation on a segment of U.S. 25E, connecting Kentucky and Tennessee and restoring Cumberland Gap to its historical appearance. The concrete pavement in the tunnel started to subside in 2001. Ground penetrating radar surveys revealed voids in many areas of the limestone roadbed aggregate beneath the pavement. To investigate possible hydrogeologic processes that may have caused favorable conditions for voids to form in the aggregate, we studied geology, groundwater flow, and groundwater chemistry in the tunnel using a variety of methods, including bore drilling, packer test, dye tracing, groundwater- and surface-flow monitoring, water-chemistry modeling, and an aggregate dissolution experiment. The study revealed that the aggregate receives a large volume of groundwater from much of the bedrock invert, but the flow velocity is too slow to transport small particles out of the aggregate. Calcite saturation indices calculated from water-chemistry data suggest that the groundwater was capable of continuously dissolving calcite, the primary mineral in the limestone aggregate. Water samples taken during different flow conditions indicate that groundwater under low-flow conditions. The dissolution experiment showed that all the limestone aggregate placed beneath the roadbed and in contact with groundwater lost mass; the highest mass loss was 3.4 percent during a 178-day period. The experiment also suggested that water with higher calcite-dissolving potential removed limestone mass quicker than water with low calcite-dissolving potential. We recommend that the limestone aggregate be replaced with noncarbonate aggregate, such as granite, to prevent dissolution and future road subsidence

A multifunctional photoacoustic/fluorescence dual-mode-imaging gold-based theranostic nanoformulation without external laser limitations

Theranostics is a new type of biomedical technology that organically combines the diagnosis and therapy of diseases. Among molecular imaging techniques, the integration of photoacoustic (PA) and fluorescence (FL) imaging modes with high sensitivity and imaging depth provides precise diagnostic outcomes. Gold nanorods (Au NRs) are well-known contrast agents for PA imaging and photothermal therapy. However, their high toxicity, poor biocompatibility, rapid clearance, and the need for an external laser source limit their application. Therefore, modification of Au NRs with carbon-based nanomaterials (CBNs) is done to obtain a multifunctional dual-mode gold-based nanoformulation (mdGC), which preforms dual-mode imaging of PA and FL. The results show that mdGC promotes tumor cell apoptosis and exhibits good antitumor performance through the mitochondria-mediated apoptotic pathway by increasing the production of intracellular reactive oxygen species, reducing mitochondrial membrane potential, and regulating the expression of apoptosis-related genes. The targeting rate of mdGC to tumor tissue is up to 20.71 ± 1.94% ID g-1; the tumor growth inhibition rate is as high as 80.44% without external laser sources. In general, mdGC is a potential multifunctional diagnostic and therapy integrated nanoformulation.J.Z., X.Y., and C.L. contributed equally to this study. This study was supported by the National Natural Science Foundation of China (81922037, 11575107, 21371115, and 22003038), the Shanghai UniversityUniversal Medical Imaging Diagnostic Research Foundation (19H00100), and Shanghai Biomedical Science and Technology Support Project (19441903600)