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Repair of periodontal and maxillofacial bone defects is a major challenge in clinical. Guided bone regeneration (GBR) is considered one of the most effective methods. However, the efficacy of currently available GBR membranes for repair is frequently limited by their poor osteogenic potential and lack of antibacterial activity. The first step in this investigation was to construct a zinc-based zeolite-imidazolate framework loaded with copper ions (Cu@ZIF-8). Following that, a novel polycaprolactone/polylactic acid/nano-hydroxyapatite/Cu@ZIF-8 (PCL/PLA/n-HA/Cu@ZIF-8) GBR membrane was developed using a simple porogen with nonsolvent-induced phase separation (NIPS) approach. The produced membrane with asymmetric porous structure (one smooth side and one rough side) possesses hydrophilicity corresponding to the roughness of its two sides. The superior mechanical property, stability of degradation, and ion release capability of the membrane all contribute to the clinical feasibility. Additionally, in vitro biological experiments demonstrated that the PCL/PLA/n-HA/Cu@ZIF-8 membrane had favorable osteogenic and antibacterial properties, which suggests the high potential for application in the GBR procedure.

Oral wounds under diabetic conditions display a significant delay during the healing process, mainly due to oxidative stress-induced inflammatory status and abnormal immune responses. Besides, the wet and complicated dynamic environment of the oral cavity impedes stable treatment of oral wounds. To overcome these, a biomimetic hydrogel adhesive was innovatively developed based on a mussel-inspired multifunctional structure. The adhesive displays efficient adhesion and mechanical harmony on the oral mucosa through enhanced bonding in an acidic proinflammatory environment. The bioadhesive hydrogel exhibits excellent antioxidative properties by mimicking antioxidative enzymatic activities to reverse reactive oxygen species (ROS)-mediated immune disorders. Experiments on oral wounds of diabetic rats showed that this hydrogel adhesive could effectively protect against mucosal wounds and obviously shorten the inflammatory phase, thus promoting the wound-healing process. Therefore, this study offers a promising therapeutic choice with the potential to advance the clinical treatment of diabetic oral wounds.

Stereochemistry can significantly affect the chemical and physical properties of synthetic polymers. Compared to the structural precision of natural biomacromolecules (e.g. proteins and nucleic acids) that are chiral and enantiopure, fully controlling the stereochemistry of synthetic polymers is considerably more challenging. However, the development of next generation polymer materials will require increasing levels of microstructural control and an in-depth understanding of structure-property relationships. Herein, we assemble an unprecedented library of enantiopure oligomers, specifically indene-maleimide-indene trimers, with identical primary structure but different stereochemistry through a novel highly stereoselective radical addition process. Full characterization of these unique trimers reveals that the structural rigidity and molecular compactness are responsible for their unique physical properties, including crystallization, glass transition temperature and optical activity. This strategy provides an innovative means to build oligomeric blocks for synthetic polymers and tailor their physical properties.

Healthy and sustainable high-quality development needs to rely on scientific planning and design of assessment system, enabling high-quality assessment to become an important tool to lead and drive high-quality development in China. A high-quality development evaluation index system is proposed, consisting of six dimensions: economic operation, innovation-driven, coordinated development, green ecology, open development, and sharing and harmony, and the temporal and spatial Differentiation in China's inter-provincial high-quality development levels are discussed after being measured using the entropy weight method. The results show that from the time dimension, China's overall high quality development level shows a fluctuating upward trend with an obvious growth rate, and Jiangsu, Zhejiang and Shanghai maintained a high level of high-quality development during this period. From the spatial dimension, it is found that China's high-quality development level has a significant positive spatial correlation between regions from 2014 to 2020, with a stable "high-high" agglomeration in the eastern coastal areas and the middle and lower reaches of the Yangtze River, the "low-high" agglomeration is mainly distributed in the central plains, and the "low-low" agglomeration effect in the western provinces and regions has spread on a larger scale after 2015, with significant performance in the north-western provinces and regions. &nbsp

Critical-sized maxillofacial bone defects have been a tough clinical challenge considering their requirements for functional and structural repair. In this study, an injectable in-situ forming double cross-linked hydrogel was prepared from gelatin (Gel), 20 mg/mL alginate dialdehyde (ADA), 4.5 mg/mL Ca

UV/sulfite systems with oxygen have recently been considered as advanced oxidation processes in view of the participation of oxysulfur radicals. However, the contribution of •OH and the efficiency of destructing emerging contaminants (ECs) in water remain largely unclear. Here, the UV/S(IV) process was applied with natural reoxygenation to degrade two typical ECs, diethyl phthalate (DEP) and bisphenol A (BPA) showing different properties. Solution pH played the key role in determining the reactive species, and both DEP and BPA were more favorably degraded at more alkaline conditions with higher utilization efficiency of SO32−. Specifically, the H•, O2•−, •OH and SO3•− were identified at acidic condition, but the amount of •OH accumulated significantly with the elevation of pH. Competitive quenching experiments showed that eaq− and •OH dominated the degradation of DEP and BPA at alkaline condition, respectively. Besides, DEP showed higher quantum efficiency for the indirect photolysis and mineralization degree than that of BPA at pH 9.2 mainly due to the direct use of the primary photoproduct. The possible transformation mechanisms of S(IV) and mineralization routes of both pollutants were proposed. This study may provide new insights into the mechanisms involved in UV/S(IV) process and a promising alternative for efficient removal of ECs in water.

Liver tumor segmentation networks are generally based on U-shaped encoder-decoder network with 2D or 3D structure. However, 2D networks lose the inter-layer information of continuous slices and 3D networks might introduce unacceptable parameters for GPU memory. As a result, 2.5D networks were proposed to balance the memory consumption and 3D context. Different from the canonical 2.5D design, which utilizes a 2D network combined with RNN, we propose a new 2.5D design called UV-Net to encode the inter-layer information in the context of 3D convolution, and reconstruct the high-resolution results with 2D deconvolution. At the same time, the multi-scale convolution structure enables multi-scale feature extraction without extra computational cost, which effectively mines structured information, reduces information redundancy, strengthens independent features, and makes feature dimension sparse, to enhance network capacity and efficiency. Combined with the proposed preprocessing method of removing mean energy, UV-Net significantly outperforms the existing methods in liver tumor segmentation and especially improves the segmentation accuracy of small objects on the LiTS2017 dataset.

Completely separating and recovering metals and nonmetals from waste printed circuit boards (WPCBs) is key to e-waste recycling. Here we proposed a novel approach, slurry or suspension electrolysis, to separate metals and nonmetals from WPCBs. The factors that impact the separation rate during the slurry electrolysis were discussed in detail. The results indicate that CuSO4·5H2O, NaCl, H2SO4, WPCBs dosage, current and time could impact metals separating from WPCBs. Increasing NaCl and H2SO4 concentration and extending electrolysis time could effectively increase the metal and nonmetal separation rate, while increasing WPCBs dosage and current have negative impacts on the metal and nonmetal separation rate. Slurry electrolysis could directly and completely separate and recover metals from WPCBs with a separation rate up to 97.79% under the conditions of 3 g WPCBs dosage in 100 mL electrolyte, 30 g/L CuSO4·5H2O, 40 g/L NaCl, 150 g/L H2SO4, 0.5 A and 9 h. The separated micro-metal powders are mainly Cu, about 86.6%, without any nonmetal powders. Copper recovered is dendritic, with a copper recovery rate up to nearly 99%. Thus, slurry electrolysis shows a prospective future in e-waste reutilization, providing a way to enrich metals for all kinds of urban mines.

Industrialized textile dyeing technology has inspired a scalable and low-cost process for immobilization of a photoredox catalyst onto commercial cotton threads to prepare unique heterogeneous cata...

Biomimetic synthesis merges the unprecedented properties of biominerals with the unique characteristics of synthetic materials to yield hybrid materials with hierarchical morphologies and tunable properties difficult to achieve via traditional physical or chemical synthesis. The biomimetic synthesis of coordination networks, such as metal–organic frameworks and amorphous coordination networks, is a relatively new member in the family of bioinspired or biomimetic materials. There is a growing interest in synthesizing organic–inorganic hybrid materials using biomimetic routes to exploit the synergistic properties of both the synthetic materials and biomaterials. These hybrid biomimetic materials show potential ground-breaking applications in nanotechnology and biomedicine ranging from gas separation to drug delivery and biocatalysis. In this review, we summarize the current state of synthesizing coordination networks using biomimetic routes, utilizing three major classes of materials, including synthetic polymers, biomolecules, and living entities. The biomimetic synthesis of coordination networks from these functional substrates has the potential to address global challenges in energy, healthcare, and environmental sustainability.

Natural fibrous cellulose (cotton) and household porous cellulose (sponge) as supporting monolithic materials were employed for the immobilization of a photoredox catalyst to prepare unique heterogeneous catalyst composites, which were able to effectively regulate controlled radical polymerization of diverse monomers under low energy visible light. Metalloporphyrin (e.g. zinc porphyrin), a highly efficient photocatalyst for photoinduced electron/energy transfer–reversible addition–fragmentation chain transfer (PET-RAFT) polymerization, was conjugated to the supports by effortless chemical grafting approaches. By virtue of the elasticity and robustness of cellulose monoliths, separation and recovery of the catalyst was accomplished through simply squeezing and washing with negligible catalyst leaching. The recyclability of the immobilized catalyst was comprehensively assessed, suggesting that catalytic performance had been sustained in the first three cycles. It is interesting to note that the catalytic activity of the composites after three cycles decreased due to demetallation of the zinc porphyrin during polymerization. Nevertheless, using free-base porphyrin with added co-catalyst (tertiary amine as a sacrificial agent) could prevent metal contamination of the final polymer products.

137Cs+/90Sr2+ adsorption kinetics on natural Ca-bentonite under the impact of different adsorption conditions was examined in detail. The results indicate that natural Ca-bentonite shows a strong adsorption capacity for Cs+/Sr2+. The adsorption reached at equilibrium after 2 hours for Cs+. Cs+/Sr2+removal efficiency reaches the highest when the pH value is 5 to 8 and increases with the increase of Ca-bentonite adding amount. Cs+ removal efficiency increases with the increase of Cs+ initial concentration, while Sr2+ removal efficiency slightly varies around 70%. The adsorption of Cs+/Sr2+ by Ca-bentonite follows the pseudo-second-order model and is controlled by chemical adsorption. Meanwhile, the results of intraparticle diffusion modelling indicate that intraparticle diffusion is a kinetics controlling step, besides surface adsorption and liquid film diffusion.

The necessity of sustainable development in the chemical industry has continuously drawn attention to find safe, environmentally friendly and atom-economic chemical processes, which is defined in the 12 principles of green chemistry. Merging photoredox catalysis and reversible addition–fragmentation chain transfer (RAFT) polymerisation, the photoinduced electron/energy transfer (PET)-RAFT process has opened up a new way of performing reversible deactivation radical polymerisation for well-defined polymer synthesis using light as an external stimulus. While providing an increased level of control (spatiotemporal, wavelength, and intensity control) over the polymerisation, PET-RAFT has many attractive attributes (abundant catalyst availability, catalyst recyclability, selectivity and oxygen tolerance) to be green and sustainable, which is intriguing for precision polymer manufacturing in industry.

Glucagon-like peptide-1 (GLP-1) and GLP-1 receptor agonists are actively pursued as therapeutic agents for type 2 diabetes mellitus (T2DM). However, the therapeutic utility of GLP-1 is limited due to its rapid inactivation by dipeptidyl peptidase IV, and many GLP-1 receptor agonists suffer from innegligible adverse effects. In the present study, in order to develop long-acting GLP-1 derivatives with improved hypoglycemic activity, native GLP-1 (7-36)-NH2 was loaded into sterically stabilized phospholipid micelles (SSM), affording GLP-1-SSM. In vitro stability test and in vivo pharmacokinetic study demonstrated that the association of GLP-1 with SSM led to enhanced stability and drug utilization without affecting its insulinotropic and glucose-lowering activities. Single and multiple glucose tolerance tests confirmed that GLP-1-SSM was a long-acting antidiabetic agent comparable or even better than exendin-4. More importantly, preclinical studies found out that a chronic twice daily treatment of GLP-1-SSM in type 2 diabetic db/db mice suppressed body weight gain and food uptake, decreased HbA1c value, and restored the glucose tolerance ability. Collectively, our results suggest that GLP-1-SSM is a promising therapy for the treatment of T2DM and deserves further investigation.

It is hard to segmentation brain MR images for the bias fields. In this paper, a new fuzzy anisotropic diffusion function is presented to reduce the effect of the noise. We use Legendre polynomial functions to reconstruct the bias field, which make the entropy of the recovered image be smallest. But it needs to compute a lot of parameters to reconstruct the bias. The traditional method uses the gradient descending method to compute the parameters. The method plunges into local best easily. In order to deal with this problem, Particle swarm optimization (PSO) method is analyzed. A new particle swarm technique is proposed that incorporates initial location information and use mutate operation make the particles away from local maxima. The experiments show that the new method can get accurate result robustly.

The concentrated metal scraps, obtained by the mechanical process for waste printed circuit board (WPCB) recycling, were pressed as the anode, which was directly electrolyzed to produce copper powders. The effects of CuSO4·5H2O, NaCl and H2SO4 concentration, current density and electrolysis time on current efficiency and copper powder size were investigated in detail. The results indicated that current efficiency increased rapidly as the increase of CuSO4·5H2O, H2SO4 concentration and current density. The obtained copper powders became finer with the increase of current density and NaCl concentration; and copper powders became coarser with the increase of CuSO4·5H2O concentration. Under the optimum conditions (50 g/L CuSO4·5H2O, 40 g/L NaCl, 118 g/L H2SO4, 80 mA/cm2 for 3 h), current efficiency was the highest (98.12%) and the particle size was the finest (9.35 μm). The experimental studies also revealed that the purity of copper obtained at the highest current efficiency was higher to 98.06%. Produced copper powders were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). XRD analysis indicated that copper was the main phase; SEM analysis showed that dendritic structure was the main characteristic of the obtained copper powders; TEM results indicated that at the end of the dendritic structure, the copper surface was coated with a layer of dense Cu2O. It is believed that the process is effective for copper recovery from concentrated WPCB metal scraps.

137Cs+/90Sr2+ adsorption kinetics on natural Ca-bentonite under the impact of different adsorption conditions was examined in detail. The results indicate that natural Ca-bentonite shows a strong adsorption capacity for Cs+/Sr2+. The adsorption reached at equilibrium after 2 hours for Cs+. Cs+/Sr2+removal efficiency reaches the highest when the pH value is 5 to 8 and increases with the increase of Ca-bentonite adding amount. Cs+ removal efficiency increases with the increase of Cs+ initial concentration, while Sr2+ removal efficiency slightly varies around 70%. The adsorption of Cs+/Sr2+ by Ca-bentonite follows the pseudo-second-order model and is controlled by chemical adsorption. Meanwhile, the results of intraparticle diffusion modelling indicate that intraparticle diffusion is a kinetics controlling step, besides surface adsorption and liquid film diffusion.

137Cs+/90Sr2+-containing radioactive wastewater is one of the most important problems that the world has been facing with. A by-product, activated porous calcium silicate, is generated at high levels by the pre-desiliconizing and soda-lime-sintering processes for producing Al2O3 from high-alumina fly ash. In order to examine if this by-product could be used as an absorbent for removal of 137Cs+/90Sr2+ from radioactive wastewater, various parameters, such as pH, adsorbent dose, contact time, and initial concentration, were discussed. Results indicated that the equilibrium reached in about 2 hr. Activated porous calcium silicate was highly pH sensitive and able to remove Cs+/Sr2+ in a near-neutral environment. The adsorption equilibrium was best described by Freundlich isotherm equations, and the adsorption of Cs+/Sr2+ was a physical process. The adsorption kinetic data could be better fitted by the pseudo-second-order model, and the adsorption was controlled by multidiffusion. Current study showed that act...

Tropical savannas cover over 20% of land surface. They sustain a high diversity of mammalian herbivores and promote frequent fires, both of which are dependent on the underlying grass composition. These habitats are typically dominated by relatively few taxa, and the evolutionary origins of the dominant grass species are largely unknown. Here, we trace the origins of the genus Themeda, which contains a number of widespread grass species dominating tropical savannas. Complete chloroplast genomes were assembled for seven samples and supplemented with chloroplast and nuclear ITS markers for 71 samples representing 18 of the 27 Themeda species. Phylogenetic analysis supports a South Asian origin for both the genus and the widespread dominant T. triandra. This species emerged ~1.5 Ma from a group that had lived in the savannas of Asia for several million years. It migrated to Australia ~1.3 Ma and to mainland Africa ~0.5 Ma, where it rapidly spread in pre-existing savannas and displaced other species. Themeda quadrivalvis, the second most widespread Themeda species, is nested within T. triandra based on whole chloroplast genomes, and may represent a recent evolution of an annual growth form that is otherwise almost indistinguishable from T. triandra. The recent spread and modern-day dominance of T. triandra highlight the dynamism of tropical grassy biomes over millennial time-scales that has not been appreciated, with dramatic shifts in species dominance in recent evolutionary times. The ensuing species replacements likely had profound effects on fire and herbivore regimes across tropical savannas.

¹³⁷Cs⁺/⁹⁰Sr²⁺-containing radioactive wastewater is one of the most important problems that the world has been facing with. A by-product, activated porous calcium silicate, is generated at high levels by the pre-desiliconizing and soda-lime-sintering processes for producing Al₂O₃from high-alumina fly ash. In order to examine if this by-product could be used as an absorbent for removal of ¹³⁷Cs⁺/⁹⁰Sr²⁺ from radioactive wastewater, various parameters, such as pH, adsorbent dose, contact time, and initial concentration, were discussed. Results indicated that the equilibrium reached in about 2 hr. Activated porous calcium silicate was highly pH sensitive and able to remove Cs(+)/Sr²⁺ in a near-neutral environment. The adsorption equilibrium was best described by Freundlich isotherm equations, and the adsorption of Cs⁺/Sr²⁺ was a physical process. The adsorption kinetic data could be better fitted by the pseudo-second-order model, and the adsorption was controlled by multidiffusion. Current study showed that activated porous calcium silicate has a good adsorption of Cs⁺/Sr²⁺ for their removal. However, other characteristics, such as selectivity because of coexisting cations, elution and regeneration, thermal stability, and acid resistance, should be discussed carefully before using it in an actual field.

This paper uses Legendre polynomial functions to reconstruct the bias, which make the entropy of the recovered image be smallest. In order to calculate the parameters of the basis functions, a new particle swarm technique is proposed that incorporates initial location information and use mutate operation make the particles away from local maxima. The experiments show that the new method can get accurate result robustly.

LTE-Advanced technology is required to support 100MHz channel bandwidth and transfer rates in excess of 1Gbps. The 2.6GHz band is one of the core band of LTE-Advanced technology. This paper provide the detailed design of the RF front-end. The receiver uses the traditional double-conversion superheterodyne structure, while transmitter uses a zero-IF structure, able to obtain high receiver sensitivity and channel selectivity and small size. The tests' results show that the overall system performance is generally satisfactory. In the transmitter, the maximum output power is up to 23dBm and IMD3 is better than 45dB, for the 100MHz 16-QAM signal, the modulation accuracy is better than 4.18%; in the receiver, the gain flatness is less than 2.66dB, for the 5MHz 16-QAM modulated signals within the passband, the modulation accuracy is better than 1.34%. The transceiver switch time is less than 1.72µs.

In this paper, the design of the RF front-end transceiver of base-station for 2600MHz TD-LTE-A communication which bandwidth is 100MHz is provided. High performance is obtained. For the transmitter, the IMD3 is less than −40dB when the transmitting power is 0.2W. In the signal test of 16-QAM modulation, the TX EVM is less than 1.8% under the condition of 10M symbol per second (sps), and less than 8.2% under the condition of 100M sps. For the receiver, the RX EVMs of splicing sub-carriers in each band within the pass band are no more than 2.3%. The transceiver switch time is about 1.7µs.

In this paper, the design of a high performance RF transceiver which supports wireless data-rate up to 1Gb/s is presented. The RF transceiver operates at 3.45GHz, the channel bandwidth is 100MHz. Excellent RF performance is obtained. The IMD3 is less than −40dBc when output power is 25dBm. Both TX and RX EVM are less than 3% when tested with a 20MHz TD-LTE signal. The transceiver has a 60dB dynamic gain control range both in the TX and RX link.