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• Interactive effects of natural-human factors on vegetation coverage were quantified. • The area with a probability of degeneration ≥80% covered 16.6% of study area. • Models with vegetation coverage (2000) largely accounted for the vegetation variance. • The major drivers of vegetation coverage changed with time and variables. Vegetation coverage in coastal wetlands has been significantly altered in response to multiple disturbances over recent decades. However, the major driving factor of vegetation coverage in coastal wetlands remains unclear, with natural and human factors playing interactive roles at the national scale. To identify the major controls of vegetation coverage in coastal wetlands, structural equation modeling (SEM) was conducted to quantify the relative contribution of natural and human factors to vegetation coverage in coastal wetlands in China over a 16-year period (2000–2015). The results showed that, in brief, vegetation coverage was slightly degraded (k = −0.0035) over the 2000–2015 period. The area with a probability of vegetation coverage degeneration ≥80% covered 16.6% of the study area. Most annual mean vegetation coverage was lower but improved near the sea, with inverse results obtained near land. In 2000, human1 (population and GDP, r = −0.31) and topography (r = 0.32) were the major controls of vegetation coverage. The vegetation coverage (2000) played the most important and positive role (r = 0.62, r = 0.66) in the vegetation coverage in 2015. Our findings highlight that the major drivers of vegetation coverage in coastal wetlands changed with time and selected variables. [ABSTRACT FROM AUTHOR]

• Q-switching performance of Yb:LaCOB crystal laser is investigated for the first time. • Pulsed radiation in 2-W level is produced in passively Q-switched action with 2D MoTe 2. • Maximum pulse energy of 6.6 μJ is generated. The passive Q-switching performance of an Yb:LaCa 4 O(BO 3) 3 crystal laser was investigated for the first time to our knowledge. Stable repetitively pulsed laser action was demonstrated with a 2D MoTe 2 saturable absorber under high output couplings ranging from 70% up to 95%. A maximum pulsed output power of 2.11 W was produced at a repetition rate of 357 kHz, with a slope efficiency of 32% in terms of incident pump power. The largest pulse energy, minimum pulse duration, and highest peak power achievable were, respectively, 6.6 μJ, 103 ns, and 52.4 W. Our work suggests that this relatively new monoclinic oxyborate crystal may be more advantageous over most of other Yb-ion materials in making high-energy pulsed lasers passively Q-switched with 2D saturable absorbers. [ABSTRACT FROM AUTHOR]

Sonoporation has been widely accepted as a significant tool for gene delivery as well as some bio-effects like hemolysis, bringing in high demands of looking into its underlying mechanism. A two-dimensional (2D) boundary element method (BEM) model was developed to investigate microbubble-cell interaction, especially the morphological and mechanical characteristics around the close-to-bubble point (CP) on cell membrane. Based on time evolution analysis of sonoporation, detailed information was extracted from the model for analysis, including volume expansion ratio of the bubble, areal expansion ratio of the cell, jet velocity and CP displacement. Parametric studies were carried out, revealing the influence of different ultrasound parameters ( i.e. , driving frequency and acoustic pressure) and geometrical configurations ( i.e. , bubble-cell distance and initial bubble radius). This model could become a powerful tool not only for understanding bubble-cell interactions, but also for optimizing the strategy of sonoporation, such that it could be safer and of higher efficiency for biological and medical studies especially in clinics. [ABSTRACT FROM AUTHOR]

Highlights • The ability of SPIO-albumin MB of enhancing HIFU-induced thermal effect was evaluated. • SPIO-albumin MBs lead to quicker temperature elevation rate than albumin-shelled MBs. • SPIO-albumin MBs result in higher peak temperature than albumin-shelled MBs. • HIFU-induced thermal effect was further strengthened with more SPIOs added MB’s shell. • The combination of SPIOs changes MBs’ physical properties and cavitation behaviors. Abstract High intensity focused ultrasound (HIFU) has been regarded as a promising technology for treating cancer and other severe diseases noninvasively. In the present study, dual modality magnetic ultrasound contrast agent microbubbles (MBs) were synthesized by loading the super paramagnetic iron oxide nanoparticles (SPIOs) into the albumin-shelled MBs (referred as SPIO-albumin MBs). Then, both experimental measurements and numerical simulations were performed to evaluate the ability of SPIO-albumin MBs of enhancing HIFU-induced thermal effect. The results indicated that, comparing with regular albumin-shelled MBs, the SPIO-albumin MBs would lead to quicker temperature elevation rate and higher peak temperature. This phenomenon could be explained by the changes in MBs’ physical and thermal properties induced by the integration of SPIOs into MB shell materials. In addition, more experimental results demonstrated that the enhancement effect on HIFU-induced temperature elevation could be further strengthened with more SPIOs combined with albumin-shell MBs. These observations suggested that more violent cavitation behaviors might be activated by ultrasound exposures with the presence of SPIOs, which in turn amplified ultrasound-stimulated thermal effect. Based on the present studies, it is reasonable to expect that, with the help of properly designed dual-modality magnetic MBs, the efficiency of HIFU-induced thermal effect could be further improved to achieve better therapeutic outcomes. [ABSTRACT FROM AUTHOR]

• The gabion specimen failure is mainly the opening of mesh and the crushing of a few rock-fill particles. Accompany with the opening of mesh, some rockfill may rush out. • The square gabion undergoes "square - circle - failure" in the compression test, namely square gabion first bulges to a circle shape under loading, then basically acts as cylindrical specimen. • Under quasi-static loading conditions (loading rates vary from 2 to 30 mm/min), the overall influences of loading rates are not obvious. The loading curves display similar. • The ratio of height to diameter (or side length) of the specimen (H/D) has a great effect on the mechanical characteristics of the gabion. At present, the gabion is widely used in practical engineering due to its good working performance. However, the research on the mechanical characteristics of gabion and the interaction mechanism between materials is not yet mature. Therefore, this paper, through uniaxial compression tests, mainly reveal the failure modes and evolution law of mechanical characteristics of gabion specimen involving several influence factors, such as the specimen shape (cylindrical and square), the ratio of height to diameter of the specimen (H/D, including 0.75, 1, 1.25, 1.5, 1.75, 2), and the loading rate (LR, ranging 2 ∼ 30 mm/min). Several test results show that the square gabion gradually undergoes the process of "square - circle - failure" during the compression tests, namely square gabion first develops to a circle shape, then basically experiences the same way as the cylindrical specimen. All the test results may provide valuable references for the preparation of standard test procedures for gabion specimens in the future. [ABSTRACT FROM AUTHOR]

Melanoma could be extremely lethal due to its high invasiveness and rapid proliferation, which causes thousands of deaths worldwide every year. Because of the resistance of melanoma to chemo/radio/immunotherapy, effective treatment of melanoma remains a clinically unsolved puzzle. Some efforts have been made to utilize ultrasound (US) to control the migration of melanoma cells, but the underlying mechanism is still unclear. Here, the impact of US-induced microbubble (MB) cavitation on the migration and cell cycle arrest of A375 melanoma cells was studied. To quantitatively explore the relationship between US-activated MB activity and the changes of A375 cellular response, inertial cavitation dose (ICD) was evaluated at varied acoustic driving pressures and MB concentrations. The pool data results showed that A375 cells' migrating capacity slightly fluctuated till ICD reached a certain threshold (3000 V × μs) and declined rapidly afterwards as the ICD further increased. Similar trend was observed in terms of the changes of G1-phase cell ratio. These findings suggested that, with appropriately selected parameters, MB-mediated cavitation can be effectively utilized to suppress the migration of A375 cells by reducing the proportion of cells arrested in G1 phase. [ABSTRACT FROM AUTHOR]