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Distributed Scatterers Interferometry (DS-InSAR) has been widely applied to increase the number of measurement points (MP) in complex mountainous areas with dense vegetation and complicated topography. However, DS-InSAR method adopts batch processing mode. When new observation data acquired, the entire archived data is reprocessed, completely ignoring the existing results, and not suitable for high-performance processing of operational observation data. The current research focuses on the automation of SAR data acquisition and processing optimization, but the core time series analysis method remains unchanged. In this paper, based on the traditional Sequential Estimator proposed by Ansari in 2017, a Recursive Sequential Estimator with Flexible Batches (RSEFB) is improved to divide the large dataset flexibly without requirements on the number of images in each subset. This method updates and processes the newly acquired SAR data in near real-time, and obtains long-time sequence results without reprocessing the entire data archived, helpful to the early warning of landslide disaster in the future. 132 Sentinel-1 SAR images and 44 TerraSAR-X SAR images were utilized to inverse the line of sight (LOS) surface deformation of Xishancun landslide and Huangnibazi landslide in Li County, Sichuan Province, China. RSEFB method is applied to retrieve time-series displacements from Sentinel-1 and TerraSAR-X datasets, respectively. The comparison with the traditional Sequential Estimator and validation through Global Position System (GPS) monitoring data proved the effectiveness and reliability of the RSEFB method. The research shows that Xishancun landslide is in a state of slow and uneven deformation, and the non-sliding part of Huangnibazi landslide has obvious deformation signal, so continuous monitoring is needed to prevent and mitigate possible catastrophic slope failure events. [ABSTRACT FROM AUTHOR]

With the increasing demand for decentralized systems and the widespread usage of blockchain, low throughput and high latency have become the biggest stumbling blocks in the development of blockchain systems. This problem seriously hinders the expansion of blockchain and its application in production. Most existing smart contract scheduling solutions use static feature analysis to prevent contract conflicts during parallel execution. However, the conflicts between transactions are complex; static feature analysis is not accurate enough. In this paper, we first build the dependency between smart contracts by analyzing the features. After numerous experiments, we propose a conflict model to adjust the relationship between threads and conflict to achieve high throughput and low latency. Based on these works, we propose adaptive parallel scheduling for smart contracts on the blockchain. Our adaptive parallel scheduling can distinguish conflicts between smart contracts and dynamically adjust the execution strategy of smart contracts based on the conflict factors we define. We implement our scheme on ChainMaker, one of the most popular open-source permissioned blockchains, and build experiments to verify our solution. Regarding latency, our solution demonstrates remarkable efficiency compared with the fully parallel scheme, particularly in high-conflict transaction scenarios, where our solution achieves latency levels just one-twentieth of the fully parallel scheme. Regarding throughput, our solution significantly outperforms the fully parallel scheme, achieving 30 times higher throughput in high-conflict transaction scenarios. These results highlight the superior performance and effectiveness of our solution in addressing latency and throughput challenges, particularly in environments with high transaction conflicts. [ABSTRACT FROM AUTHOR]

Understanding the intention of community residents to seek help from mental health professionals (MHPs) is essential in targeting interventions that promote the prevention and treatment of depression. This study aimed to investigate the current status of Chinese community populations' depression help-seeking intentions from MHPs and explore factors influencing the intentions. Data were used from a survey conducted in a city in central China (n = 919 aged 38.68 ± 17.34, 72.1% female). Help-seeking intentions, help-seeking attitude, depression stigma, family function and depressive symptoms were measured. The total mean score on the intent to seek help from MHPs was 11.01 ± 7.78 and most of respondents were unwilling to seek professional help. Multiple linear regression showed that participants who were students, held a positive help-seeking attitude and had low personal stigma were more likely to have the intention to seek help from MHPs. It is necessary to utilize effective interventions to improve community residents' intention to seek professional help. These include promoting the importance of seeking professional assistance, optimizing the quality of mental health services and altering residents' prejudice to seeking professional help. [ABSTRACT FROM AUTHOR]

Southern California, USA, has been suffering severe surface deformation due to its active crustal movement under the north–south compression of the Pacific Plate and North American Plate. Meanwhile, affected by groundwater extraction and recharge, oil exploitation, surface subsidence, uplift, and seasonal deformation occur commonly in this region. In this paper, multi-path SAR datasets were collected to investigate and monitor surface deformation in Southern California. The unified simultaneous least squares (USLS) approach is applied to remove the deformation discontinuity between adjacent SAR image paths. Multiple deformation patterns of structural faults, groundwater withdrawal, and oil exploitation are observed with the interferometric synthetic aperture radar (InSAR) technique. The InSAR-derived results were validated with GPS monitoring data. The correlations between land deformation and groundwater withdrawal, faults, and precipitation were intensively analyzed, finding out and mastering the magnitude and characteristics of ground deformation in Southern California. [ABSTRACT FROM AUTHOR]

SAR Interferometry (InSAR) is a powerful technique for mapping land surface deformation, but single one-dimensional (1D) InSAR line-of-sight (LOS) measurement limits its application in three-dimensional (3D) displacement retrieval. Traditional methods were developed for measuring large-scale deformation. In this paper, to retrieve the slow 3D deformation process in the Jiaju landslide, a surface-parallel flow model is applied, according to the existing geological data gained from this landslide. Nine ENVISAT ASAR images and 19 ALOS PALSAR images were collected to reconstruct the 3D deformation field. An iterative method for correcting the characteristic value (IMCCV) with maximum likelihood estimation (M-estimation) adaptively generates an accurate stochastic model. The 3D deformation measurements show that the northern part of the Jiaju landslide clearly had horizontal deformation with the largest deformation velocity exceeding 15 cm year−1, while the southern part was relatively stable. Similarly, large vertical deformation appeared in the northern part (−2 cm year−1) and little deformation occurred in the southern part (−0.5 cm year−1). Compared with GPS measurements, the standard deviation is 1.4 cm year−1 and 0.7 cm year−1 in horizontal and vertical directions, respectively. Therefore, the Jiaju landslide exhibited movements in the horizontal direction accompanied by slight settlement in the vertical direction. [ABSTRACT FROM AUTHOR]

When an electromagnetic wave passes through the atmosphere, due to variation of atmospheric parameters, its propagation path is usually altered and the propagation speed also changes. Therefore, errors will be induced in triangulation measurement with electronic surveying robots, delimiting the accuracy of trigonometric leveling. Targeting at improving the accuracy of trigonometric leveling, a correction model based on atmospheric refraction coefficients is proposed in this article. First, based on the meteorological parameters collected on-site and Rüeger equation, influence of the meteorological parameters (e.g., temperature, atmospheric pressure, humidity, and CO2) on the refractive index are analyzed. Furthermore, gradient models of temperature, humidity, and atmospheric pressure with reference to height are established. In order to build the atmospheric gradient models of the optical path, height difference between the optical path and the ground is estimated with a precise digital elevation model generated by laser scanning. On this basis, the vertical atmospheric refraction coefficient model is proposed and used to correct the trigonometric leveling data measured by surveying robots. By conducting experimental studies over two open-pit iron mines with large topographic relief and comparing with first-class leveling data, reliability of the proposed atmospheric refraction coefficient model is assessed. The outcome of this article has demonstrated that by adopting the proposed model, accuracy of trigonometric leveling can meet the requirements of second-class leveling. [ABSTRACT FROM AUTHOR]

The Kuandian County (Northeast China) has suffered frequent rockfall disasters because of its topography, geological setting, and anthropogenic activities. This research work conducts rockfall susceptibility assessment in Kuandian County by comprehensively combining the Information Content Method (ICM) with the Analytic Hierarchy Process (AHP). Firstly, information contents of the evaluation factors are calculated via statistical analysis on the existing rockfall sites. Then, weights of the evaluation factors are determined by adopting AHP. In the final step, the susceptibility value of each evaluation unit is obtained by weighted summation of the information content of each evaluation factor. The combination of ICM and AHP is able to promote the objectiveness of the evaluation process and accuracy of the evaluation results. Furthermore, in order to analyze the influence of evaluation factor setting on susceptibility, assessments using reduced number of evaluation factors are also conducted for comparative analysis. Additionally, to analyze the influence of evaluation units on susceptibility, comparative analysis on the assessment results from both slope units and grid units in a small area is performed. The susceptibility assessment results presented in this study are generally consistent with the current situation of rockfall disasters in Kuandian County, providing reliable data support for disaster prevention and mitigation. Furthermore, the outcome of this study serves as a methodological reference for rockfall risk assessment in Northeast China and other mountainous regions. [ABSTRACT FROM AUTHOR]

Developmental delay (DD), or intellectual disability (ID) is a very large group of early onset disorders that affects 1–2% of children worldwide, which have diverse genetic causes that should be identified. Genetic studies can elucidate the pathogenesis underlying DD/ID. In this study, whole-exome sequencing (WES) was performed on 225 Chinese DD/ID children (208 cases were sequenced as proband-parent trio) who were classified into seven phenotype subgroups. The phenotype and genomic data of patients with DD/ID were further retrospectively analyzed. There were 96/225 (42.67%; 95% confidence interval [CI] 36.15–49.18%) patients were found to have causative single nucleotide variants (SNVs) and small insertions/deletions (Indels) associated with DD/ID based on WES data. The diagnostic yields among the seven subgroups ranged from 31.25 to 71.43%. Three specific clinical features, hearing loss, visual loss, and facial dysmorphism, can significantly increase the diagnostic yield of WES in patients with DD/ID (P = 0.005, P = 0.005, and P = 0.039, respectively). Of note, hearing loss (odds ratio [OR] = 1.86%; 95% CI = 1.00-3.46, P = 0.046) or abnormal brainstem auditory evoked potential (BAEP) (OR = 1.91, 95% CI = 1.02–3.50, P = 0.042) was independently associated with causative genetic variants in DD/ID children. Our findings enrich the variation spectrums of SNVs/Indels associated with DD/ID, highlight the value genetic testing for DD/ID children, stress the importance of BAEP screen in DD/ID children, and help to facilitate early diagnose, clinical management and reproductive decisions, improve therapeutic response to medical treatment. [ABSTRACT FROM AUTHOR]

Background: Recent studies have demonstrated that multidrug resistance (MDR) is a critical factor in the low efficacy of cancer chemotherapy. The main mechanism of MDR arises from the overexpression of P-glycoprotein (P-gp), which actively enhances drug efflux and limits the effectiveness of chemotherapeutic agents. Results: In this study, we fabricated a "combo" nanoagent equipping with triple synergistic strategies for enhancing antitumor efficacy against MDR cells. Tumor homing-penetrating peptide endows the nanosystem with targeting and penetrating capabilities in the first stage of tumor internalization. The abundant amine groups of polyethylenimine (PEI)-modified nanoparticles then trigger a proton sponge effect to promote endo/lysosomal escape, which enhances the intracellular accumulation and retention of anticancer drugs. Furthermore, copper tetrakis(4-carboxyphenyl)porphyrin (CuTCPP) encapsulated in the nanosystem, effectively scavenges endogenous glutathione (GSH) to reduce the detoxification mediated by GSH and sensitize the cancer cells to drugs, while simultaneously serving as a photoacoustic imaging (PAI) contrast agent for image visualization. Moreover, we also verify that these versatile nanoparticles in combination with PD-1/PD-L1 blockade therapy can not only activate immunological responses but also inhibit P-gp expression to obliterate primary and metastatic tumors. Conclusion: This work shows a significant enhancement in therapeutic efficacy against MDR cells and syngeneic tumors by using multiple MDR reversing strategies compared to an equivalent dose of free paclitaxel. [ABSTRACT FROM AUTHOR]

The purpose of this study was to develop a sonosensitizer-loaded multi-functional ultrasound (US) contrast agent for both tumour therapy and imaging. The hematoporphyrin (HP)-encapsulated poly(lactic-co-glycolic acid) microbubbles (HP-PLGA-MBs) were prepared and filled with perfluorocarbon gases. The enhancement of US imaging and its sonodynamically induced anti-tumour effect were evaluated by both in vitro and in vivo experiments. The HP-PLGA-MBs have a narrow size distribution and smooth surface with a mean diameter of 702.6 ± 56.8 nm and HP encapsulation efficiency of 63.50 ± 1.26% and drug-loading efficiency of 2.15 ± 0.13%. The HP-PLGA-MBs could well enhance the ultrasound imaging both in vitro and in vivo. A significant anti-tumour effect was obtained by HP-PLGA-MBs mediated sonodynamic therapy. The tumour growth rate and the tumour proliferation index were the lowest in the HP-PLGA-MBs plus sonication group. And the tumour cell apoptotic index was the biggest in the HP-PLGA-MBs plus sonication group. In conclusion, a sonosensitizer-loaded multi-functional contrast agent was constructed and the feasibility was demonstrated, which might provide a novel strategy for tumour imaging and therapy. [ABSTRACT FROM AUTHOR]

BACKGROUND: In recent years, molecular imaging combined with medical imaging technology and targeted molecular probes have gradually become a research focus. The targeted tissues at the molecular level can be observed using molecular imaging, medical imaging technology, and targeted molecular probes in combination to realize non-invasive imaging of the occurrence and development of the diseases. OBJECTIVE: To develop the magnetic targeted nanoparticle probes, observe the ultrasound/CT/MRI imaging properties in vitro, and investigate their targeting ability to rat hepatic stellate cells in vitro. METHODS: Taking poly(lactic-co-glycolic acid) (PLGA) polymer as the shell, cyclic arginine-glycine-aspartic acid (eRGO) octapeptide as the ligand, targeted magnetic nanoparticles with superparamagnetic Fe3O4 embedded in the shell and perfluorooctyl bromide(PFOB) loaded in the core were prepared by double emulsion evaporation method. The physical and chemical properties of the nanoparticles were detected. The ultrasound/CT/MRI multi-modal imaging properties of the nanoparticles at different concentrations diluted with double-distilled water were tested in vitro. Cyclic RGD peptide immobilization on PLGA-Fe3O4-PFOB NPs was completed through the amide condensation reaction. The conjugation efficiency of the eRGO on PLGA-Fe3O4-PFOB NPs and targeting ability of targeted magnetic nanoparticles in vitro were verified. Cytotoxicity experiments were used to measure the toxic effects of nanoparticles at different concentrations on BRL-3A cells in each group. RESULTS AND CONCLUSION: The targeted magnetic nanoparticles with the average size of (221.5±60.3) nm were uniform in dispersion and size. The prepared individual nanoparticle was spherical with the superparamagnetic Fe3O4 scattered on the shell. The encapsulation rate of Fe3O4 was 38%. In vitro ultrasound imaging and CT imaging signal decreased gradually as the concentrations of the nanoparticle suspension decreased. The T2-weighted signal of MRI decreased gradually with the increase of the concentrations of magnetic particle Fe3O4. Flow cytometry results showed that 94.13% of the eRGD was bound to the nanoparticles. In vitro cell targeting experiments showed that compared to PLGA-Fe3O4-PFOB NPs, cRGD-PLGA-Fe3O4-PFOB NPs exhibited greater cell targeting and affinity efficiency to hepatic stellate cells. Cytotoxicity experiments results showed the nanoparticles had no significant influence on cell viability of the BRL-3A cells. These results suggest that targeted magnetic nanoprobe cannot only be used as a multi-modal imaging contrast agent for ultrasound/CT/MRI, but also exhibits a strong specific affinity to rat hepatic stellate cells in vitro. It has great potential for the early diagnosis of liver fibrosis. [ABSTRACT FROM AUTHOR]

Nanoprobes are small enough to circulate within the vasculature and can reach tumour tissues through the endothelial gap, providing a new strategy for accurate tumour monitoring and imaging-guided antitumour therapy at the molecular level. Both photoacoustic and ultrasonic imaging are noninvasive tools for cancer detection via the application of nanoprobes. In this study, a polymeric multifunctional nanoparticle probe loaded with gold nanorods (Au-NRs) and liquid perfluorocarbon (perfluorinated hexane/PFH) and conjugated to a monoclonal antibody (MAGE-1 antibody) to melanoma-associated antigens (MAGE) targeting melanoma was successfully prepared by the double emulsion and carbodiimide methods as a targeted photoacoustic/ultrasound dual-mode imaging contrast agent (MAGE-Au-PFH-NPs). Cell-targeting experiments in vitro showed large amounts of MAGE-Au-PFH-NPs surrounding B16 melanoma cells in the targeted group. The photoacoustic signal in the targeted group was significantly increased, and the duration was longer than that in the untargeted group in vivo . The photoacoustic signal of the nanoprobes was enhanced with increased Au-NR concentration in the photoacoustic experiment in vitro . The enhanced signal was observed by ultrasound after 808-nm laser irradiation. A cytotoxicity and biocompatibility test showed that MAGE-Au-PFH-NPs exhibited good biological safety. The MAGE-Au-PFH-NPs can be used as a photoacoustic/ultrasound dual-mode contrast agent to lay the foundation for a promising new approach for the noninvasive targeting, monitoring and treatment of tumours. [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]

Variations in flowering time and plant architecture have a crucial impact on crop biomass and yield, as well as the aesthetic value of ornamental plants. Aechmea fasciata, a member of the Bromeliaceae family, is a bromeliad variety that is commonly cultivated worldwide. Here, we report the characterization of AfSPL14, a squamosa promoter binding protein-like gene in A. fasciata. AfSPL14 was predominantly expressed in the young vegetative organs of adult plants. The expression of AfSPL14 could be upregulated within 1 h by exogenous ethephon treatment. The constitutive expression of AfSPL14 in Arabidopsis thaliana caused early flowering and variations in plant architecture, including smaller rosette leaves and thicker and increased numbers of main inflorescences. Our findings suggest that AfSPL14 may help facilitate the molecular breeding of A. fasciata, other ornamental and edible bromeliads (e.g., pineapple), and even cereal crops. [ABSTRACT FROM AUTHOR]