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Graphical abstract Abstract Breast cancer is a severe threat to the health and lives of women due to its difficult early diagnosis and the unsatisfactory therapeutic efficacy of breast cancer treatments. The development of theranostic strategies to combat breast cancer with high accuracy and effectiveness is therefore urgently needed. In this study, we describe a near-infrared (NIR) light-controllable, targeted and biocompatible drug delivery nanoplatform (PFH-PTX@PLGA/SPIO-Her) for photoacoustic (PA)/ultrasound (US) bimodal imaging-guided photothermal (PTT)/chemo synergistic cancer therapy of breast cancer. Carboxyl-modified PEGylated poly (lactic-co-glycolic acid) (PLGA-PEG-COOH) constituted the skeleton of the nanoplatform. Especially, the antibody Herceptin was modified onto the surface of nanoplatform for active HER2-targing to facilitate the tumor accumulation of the nanoplatform. The encapsulated superparamagnetic iron oxide (SPIO) nanoparticles could be employed as an excellent PA imaging agent to guide tumor therapy. When exposed to NIR light, the SPIO also could transform NIR light into thermal energy for photothermal ablation of tumor. The NIR-induced thermal effect subsequently triggered the optical droplet vaporization (ODV) of perfluorohexane (PFH) to generate PFH gas bubbles, which not only achieved the US imaging enhancement, but also contributed to the release of loaded paclitaxel (PTX) from the nanoplatform for significantly improving PTT therapeutic efficacy. Our results demonstrated that the targeted tumor accumulation, accurate real-time bimodal imaging, and the abundant drug release at the tumor site were all closely associated with the PTT therapeutic efficacy. Therefore, the theranostic nanoplatform is a very promising strategy for targeted imaging-guided photothermal/chemo synergistic tumor therapy with high therapeutic efficacy and minimized side effects. Statement of Significance Breast cancer is the most frequent cancer in women. Herein, we successfully developed a light-controllable and HER2 targeted theranostic nanoparticels (PFH-PTX@PLGA/SPIO-Her) as a specific drug delivery nanoplatform to overcome the low accuracy of tumor detection and the low specificity of traditional chemo-therapeutic protocols. The study demonstrated that PFH-PTX@PLGA/SPIO-Her could actively target to breast cancer cells with positive HER2 expression. The biocompatible PFH-PTX@PLGA/SPIO-Her nanoparticles as both photoacoustic/ultrasound bimodal imaging agents, photothermal-conversion nanomaterials (photothermal hyperthermia) and controllable drug delivery nanoagents (optical droplet vaporization) have completely eradicated the tumor without severe side effects. The theranostic strategy not only integrates strengthens of traditional imaging or therapeutic modalities, but also paves a new way for the efficient cancer treatment by taking the advantage of quickly-developing nanomedicine. [ABSTRACT FROM AUTHOR]

InSAR technology provides a powerful tool to detect potentially unstable slopes across wide areas and to monitor surface displacements of a single landslide. However, conventional time series InSAR methods such as persistent scatterer interferometry (PSI) and small-baseline subset (SBAS) can rarely identify sufficient measurement points (MPs) in mountainous areas due to decorrelations caused by steep terrain and vegetation coverage. In this study, we developed a new InSAR approach, coherent scatterer InSAR (CSI), to map landslide surface displacements in the radar line-of-sight (LOS) direction by combining persistent scatterers (PS) and distributed scatterers (DS). The key ideas of CSI include the employment of the generalized likelihood ratio (GLR) test for the identification of statistically homogeneous pixels (SHPs) and the use of the phase linking algorithm to estimate optimal phase for each DS pixel. The joint exploitation of PS and DS targets dramatically increases the spatial density of MPs, which makes the phase unwrapping more reliable. To demonstrate the effectiveness of the CSI approach, we applied it to retrieve the historical displacements of the Jiaju landslide in Danba County of southwest China using 19 L-band ALOS PALSAR images (2006–2011) and nine C-band ENVISAT ASAR images (2007–2008). Multiple comparisons clearly illustrated the big advantages of CSI over PSI and SBAS in mapping landslide displacements with more details owing to much higher (> 10 times) MP density. Furthermore, the superiority of L-band SAR data over C-band for landslide investigation in rural environments was confirmed. Quantitative validation of the CSI results for PALSAR data against in-situ GPS measurements suggested an accuracy of about 10.5 millimeters per year (mm/year) in terms of root mean square error (RMSE). Afterwards, the spatial-temporal characteristics of the Jiaju landslide surface displacements were summarized, with a new upper boundary for the active northern part delineated. Particularly, the northern part of the landslide moved faster than the southern part, exhibiting a maximum LOS displacement rate of around 120 mm/year. Subsequently, the fluvial erosion by the Dajinchuan River was identified as the predominant impact factor for the instability of the Jiaju landslide. Finally, the major problems and challenges for the application of CSI method were discussed, and the conclusions were given. [ABSTRACT FROM AUTHOR]

Abstract: Objective: The purpose of this study was to explore the feasibility of using ultrasound-targeted microbubble destruction to treat liver fibrosis induced by hepatocyte growth factor (HGF). Methods: Forty Wistar rats were divided into five groups after the models of liver fibrosis were prepared: (1) HGF, ultrasound, and microbubbles (HGF+US/MB); (2) HGF and ultrasound (HGF+US); (3) HGF and microbubbles (HGF+MB); (4) HGF (HGF); and (5) model alone (MA). All rats were killed after being transfected for 14 days. Recovery of the liver was detect by diffusion-weighted imaging (DWI) and pathological methods. Collagen I expression was detected by immunohistochemistry. Hepatocyte growth factor expression in the liver was detect by western blotting. Results: The results of DWI and pathological examination showed the recovery of liver in HGF+US/MB group were better than those of other groups. In HGF+US/MB group, collagen I expression was less, and HGF protein was the highest among all the groups. Conclusions: Ultrasound-targeted microbubble destruction could deliver HGF into the fibrotic liver and produce an antifibrosis effect, which could provide a novel strategy for gene therapy of liver fibrosis. [Copyright &y& Elsevier]

Investigation of the spatio-temporal patterns of dune migration in a large-scale area with optical remote sensing techniques can help us to better understand aeolian phenomena and mitigate sand-dust disasters. With the rapid growth in data volume, extracting more accurate dune displacement time series and rates from optical observations has become possible; however, the method is not yet fully fledged. To address this issue, we propose an extended algorithm for the mature optical imagery cross-correlation (OICC) technique based on Landsat-8 (L8) and Sentinel-2 (S2) acquisitions. The main innovative points of this algorithm are: 1) the proposed pairing strategy for the OICC processing; 2) the modularized post-processing procedures for noise removal; and 3) the introduction of singular value decomposition (SVD) time-series inversion of the redundant optical observations to quantify the dune migration. To test the effectiveness of this algorithm, it was applied in the study of dune migration near Minqin Oasis in northwestern China, using enriched L8 and S2 images collected between April 2013 and April 2018. Compared with the original OICC results in stable areas, the post-processing and inversion of the proposed algorithm reduce the uncertainty by around 22–35% and 3–5% for L8, 29–48% and 5–12% for S2, respectively. The cross-comparison between the L8- and S2-derived displacement time series shows high consistency, and presents a lower uncertainty than the result of the traditional no-inversion method. Furthermore, the derived displacement rates show spatial patterns that are similar to those of the manually digitized results obtained with historical Google™ Earth (GE) images. These comparisons show the advantage of the proposed algorithm in automatically and accurately quantifying dune migration. Taking into account these measurements, the spatio-temporal evolution patterns of dune migration in the study area were analyzed. From the spatial perspective, the sand dunes move along a northwest-southeast axis with four detected transport pathways. Our research also shows that around 1087.7 km2 of dune fields present an active status. The active sand dunes are currently encroaching on around 155.5 km2 and 4.4 km2 of land each year outside and inside the oasis, respectively, representing a problem of rapid desertification. Temporally, the displacement time series along the dominant migration direction appears as seasonal variations that are seemly consistent with the changes in local atmospheric conditions. The proposed algorithm provides a new perspective to investigate the spatio-temporal evolution of dune migration with medium-resolution L8 and S2 optical datasets. Image 1 • - Design one new image pairing strategy for L8 and S2. • - Apply the inversion strategy of optical images to quantify dune migration. • - Interpret the spatio-temporal evolution patterns of dune migration. • - Evaluate the desertification near Minqin oasis. [ABSTRACT FROM AUTHOR]