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With the rising incidence of various diseases in China and the constant development of the pharmaceutical industry, there is a growing demand for floxacin-type antibiotics. Due to the large-scale production and high cost of waste treatment, the parent drug and its metabolites constantly enter the water environment through domestic sewage, production wastewater, and other pathways. In recent years, the pollution of the aquatic environment by floxacin has become increasingly serious, making the technology to degrade floxacin in the aquatic environment a research hotspot in the field of environmental science. Metal–organic frameworks (MOFs), as a new type of porous material, have attracted much attention in recent years. In this paper, four photocatalytic materials, MIL-53(Fe), NH2-MIL-53(Fe), MIL-100(Fe), and g-C3N4, were synthesised and applied to the study of the removal of ofloxacin and enrofloxacin. Among them, the MIL-100(Fe) material exhibited the best photocatalytic effect. The degradation efficiency of ofloxacin reached 95.1% after 3 h under visible light, while enrofloxacin was basically completely degraded. The effects of different materials on the visible photocatalytic degradation of the floxacin were investigated. Furthermore, the photocatalytic mechanism of enrofloxacin and ofloxacin was revealed by the use of three trappers (▪O2−, h+, and ▪OH), demonstrating that the role of ▪O2− promoted the degradation effect of the materials under photocatalysis. [ABSTRACT FROM AUTHOR]

In this paper, we put forward a class of weighted extended tree-like fractals and further use them as test bed to unveil the impact of weight heterogeneity on random walks. Specifically, a family of weighted extended tree-like fractals are first proposed, which are parameterized by a growth parameter m and weight parameter w. Then, we explore standard weight-dependent walk on the networks by deploying three traps at initial three nodes. To this end, we derive analytically the average trapping time (ATT) to measure the trapping efficiency and the obtained results show that depending on values of w , ATT may grow sub-linearly, linearly and super-linearly with the network size. Besides, it can also quantitatively impact the leading behavior and pre-factor of ATT simultaneously. Finally, more challenging mixed weight-dependent random walk that takes non-nearest-neighbor hopping is addressed. Analytical solutions of ATT derived under this new scenario imply that weight parameter w still can qualitatively, quantitatively steer leading behavior and quantitatively affect pre-factor of ATT. As to the stochastic parameter controlling mixed random walk, it could only impact the pre-factor of ATT and only have negligible effect on the leading behavior of ATT. In summary, this work could further augment our understanding of random walks on networks. [ABSTRACT FROM AUTHOR]

We propose a surface measurement method based on optical frequency comb heterodyne interferometry ranging. A digital micromirror device is used to establish a single-pixel detection system without a mechanical scanning device and realize high-speed sampling. The measurement range of the step height is extended by synthetic wavelength interferometry from half of the carrier wavelength to half of the synthetic wavelength (40 μm in this system). Thus, a sample composed of three gauge blocks and an MEMS device of the teardrop-shaped groove were measured with an accuracy of 5 nm and a measurement time of 27 ms. [ABSTRACT FROM AUTHOR]

A surface acoustic wave (SAW)-driven acoustofluidic chip of high energy efficiency is proposed through model analysis. The chip supports propagation of Lamb waves in the lid above a fluid-filled channel. Eigenmode resonance in the on-chip channel is then achieved by coupling both the SAWs and the Lamb waves into the fluid. Specifically, the phase velocity of the Lamb mode equals the SAW speed along the substrate, and the leaky angles of both match that required by the expected channel mode. Compared to resonant SAW acoustofluidics (RSA), Lamb wave coupled RSA can make the energy tripled or higher. Meanwhile, the obtained resonance frequency deviates very slightly from the designed value, limiting the error to 0.5, while RSA chips exhibit errors as high as 5.7. The proposed design protocol can help to promote the energy efficiencies and contain the in-channel temperature rise and resonance frequency deviations in SAW acoustofluidics. [ABSTRACT FROM AUTHOR]

How to effectively control the trapping process in complex systems is of great importance in the study of trapping problem. Recently, the approach of delayed random walk has been introduced into several deterministic network models to steer trapping process. However, exploring delayed random walk on pseudo-fractal web with the co-evolution of topology and weight has remained out of reach. In this paper, we employ delayed random walk to guide trapping process on a salient deterministic weighted scale-free small-world network with the co-evolution of topology and weight. In greater detail, we first place a deep trap at one of initial nodes of the network. Then, a tunable parameter p is introduced to modulate the transition probability of random walk and dominate the trapping process. Subsequently, trapping efficiency is used as readout of trapping process and average trapping time is employed to measure trapping efficiency. Finally, the closed form solution of average trapping time (ATT) is deduced analytically, which agrees with corresponding numerical solution. The analytical solution of ATT shows that the delayed parameter p only modifies the prefactor of ATT, and keeps the leading scaling unchanged. In other words, ATT grows sublinearly with network size, whatever values p takes. In summary, the work may serves as one piece of clues for modulating trapping process toward desired efficiency on more general deterministic networks. [ABSTRACT FROM AUTHOR]

• 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]

Sonodynamic therapy (SDT) activated by ultrasound is attractive as a potential alternative to conventional phototriggered therapies owing to the deeper penetration depth and the absence of phototoxicity. Nevertheless, the low quantum yield of nano‐sonosensitizer and the tumor hypoxia remain significant challenges for SDT. Herein, a novel TiO2‐based nano‐sonosensitizer is reported to bilaterally enhance the quantum yield by simultaneous integration of precious metal Pt nanoparticles (NPs) and an oxygen‐deficient layer. Furthermore, the hollow cavity of TiO2 serves as a reservoir to load doxorubicin, an anticancer drug for chemotherapy as well as a molecular sonosensitizer for SDT. The decorated Pt NPs act as nanozymes to catalyze the decomposition of endogenous hydrogen peroxide for the generation of oxygen to alleviate tumor hypoxia, reduce resistance to chemotherapy, and provide sufficient oxygen source for subsequently facilitating SDT‐induced reactive oxygen species production. The high chemo‐sonodynamic synergistic efficacy is systematically demonstrated both in vitro and in vivo. More importantly, it is believed that the novel design and the new finding in the synthesis of Pt–TiO2 heterostructures can be popularized for the preparation and application of the semiconductor‐based nanoplatforms in many fields. [ABSTRACT FROM AUTHOR]

In modelling acoustofluidic chips actuated by surface acoustic waves (SAWs) and using polydimethylsilane (PDMS) as a channel material, reduced models are often adopted to describe the acoustic behaviors of PDMS. Here, based on a standing SAW (SSAW) acoustophoresis chip, we compared three different descriptions of a PDMS chamber and looked into in-chamber physical fields and ensuing particle motion processes through finite element (FE) simulations. Specifically, the PDMS domain was considered as an elastic solid material, a non-flow fluid, and a lossy wall, respectively. The major findings include: (a) the shear waves that propagated in a solid PDMS wall did not influence the in-chamber pressure and ARF fields severely, but induced an observable difference in the acoustic streaming (AS) patterns, and distinctly changed the trajectories of polystyrene particles, especially those whose radii were below 1.5 μm; and (b) the equivalent damping coefficients were linearly dependent on the SAW frequency, characterized by a fixed loss per wavelength, indicating the wave leakage at the interface being the main source of the transmission loss of SAWs. Meanwhile, the acoustic radiation force (ARF) can be overestimated when describing PDMS as a lossy wall, especially at the bottom corners of the chamber, which could cause inaccurate predictions of the motion of big particles. Based on the damping mechanism, a rough protocol is provided for scaling of pressure fields between different models. Some suggestions for device designs and operations are also given based on the obtained findings. [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]

Multiple-input multiple-output (MIMO) radar is an enabling technique for high-resolution imaging, which is especially useful for near-field electromagnetic scattering diagnosis of complex targets. Among others, high sidelobes and radar cross section (RCS) calibration uncertainty are the major challenges for such applications, due to array nonuniformity, imperfect channels, and antenna pattern tapering. These shortcomings prevent a MIMO radar from obtaining high-quality images with enough dynamic range and RCS accuracy. In this paper, we develop a complete solution for these problems. A novel adaptive weighting technique is proposed, where the complex weights are optimized for exact amplitude and phase error calibration of a MIMO array and for azimuth sidelobe reduction. A MIMO filtered backprojection algorithm is developed for image formation with improved RCS calibration accuracy, where propagation path-loss, antenna pattern tapering, and phase distortion due to the near-field spherical wave front are compensated. Both indoor and outdoor field test results are presented to show the high-quality images obtained using the proposed techniques, demonstrating the applicability of a MIMO radar for diagnostic RCS imaging of complex targets. [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]

Influenced by the interplay of global climate change and urbanization, urban plants have become increasingly homogenized in China. However, regional effects of biotic homogenization cannot be clearly explained due to the lack of continuous large-scale data. Thus, we explored the characteristics and regional effects of biotic homogenization, which not only contributes to the improvement of urban biodiversity, but also has important value for human well-being. Here, we analyzed the woody plants of 101 cities in 8 major urban agglomerations in China. The diversity patterns and influencing factors were explored using generalized additive, geographically weighted regression, and structural equation models. The main results were as follows: (1) The issue of woody plant homogenization is primarily manifested in urban greening species in China. (2) The characteristics of woody plant homogenization exhibit notable regional effects at a large scale. (3) Latitude, urban area, altitude and climatic factors all impact the woody plant homogenization. Thus, we found that the homogenization characteristics of urban greening species exhibit regional variations, influenced by both natural and anthropogenic factors. Finally, we suggested that urban biodiversity management should be considered specific regional environmental, both to meet the needs of residents. [Display omitted] • Woody plants in urban greening had a more similar species composition. • Homogenization characteristics are more obvious in northern China, affected by altitude, climate and human activities. • We examine the regional effects on woody plant diversity patterns. • Suggestions were provided on the scientific application and management of urban greening woody plants. [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]