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Ice‐templated porous biomaterials possess transformative potential in regenerative medicine; yet, scaling up ice‐templating processes for broader applications—owing to inconsistent pore formation—remains challenging. This study reports an innovative semi‐solid freeze‐casting technique that draws inspiration from semi‐solid metal processing (SSMP) combined with ice cream‐production routines. This versatile approach allows for the large‐scale assembly of various materials, from polymers to inorganic particles, into isotropic 3D scaffolds featuring uniformly equiaxed pores throughout the centimeter scale. Through (cryo‐)electron microscopy, X‐ray tomography, and finite element modeling, the structural evolution of ice grains/pores is elucidated, demonstrating how the method increases the initial ice nucleus density by pre‐fabricating a semi‐frozen slurry, which facilitates a transition from columnar to equiaxed grain structures. For a practical demonstration, as‐prepared scaffolds are integrated into a bilayer tissue patch using biodegradable waterborne polyurethane (WPU) for large‐scale oral mucosal reconstruction in minipigs. Systematic analyses, including histology and RNA sequencing, prove that the patch modulates the healing process toward near‐scarless mucosal remodeling via innate and adaptive immunomodulation and activation of pro‐healing genes converging on matrix synthesis and epithelialization. This study not only advances the field of ice‐templating fabrication but sets a promising precedent for scaffold‐based large‐scale tissue regeneration. [ABSTRACT FROM AUTHOR]

Abstract In response to sexual assault on campus, most Australian universities have websites that educate the university community on sexual consent and policies that deal with sexual misconduct. This article [...]

To reduce the low-order vibrations of high-voltage transmission towers in response to strong winds, a tuned mass damper (TMD) that uses eddy current damping (ECD) with omnidirectional damping function (ECD-TMD) is proposed here. Compared with previous similar devices, the outstanding advantage of the proposed ECD-TMD lies in its use of non-contact ECD, structural simplicity, lack of internal friction, ability to sense micro-vibrations, and in the asymmetric cantilever pendulum structure that enables omnidirectional vibration suppression. Aero-elastic model wind tunnel test and field measurements were used for analyzing and validating the vibration responses of a 50-m-tall transmission tower with and without the proposed ECD-TMD. The results demonstrated that the proposed ECD-TMD reduced transmission tower's first-order bending vibrations along and across the direction of transmission line. For the mass ratio of approximately 2%, approximately 18–27% reduction of acceleration and 10–25% reduction of displacement occurred. Because the first-order resonance of the tower body in response to wind accounts for a small fraction of the background response, the addition of a TMD device suppresses structural wind vibrations in a limiter manner but can significantly increase the first-order bending damping ratio of the tower. [ABSTRACT FROM AUTHOR]

Although the application of biological materials has shown potential in improving the environment of salinized soil, the impact on the transformation of soil phosphorus forms in salinized soil, especially when combined with B. mucilaginosus (BM), has rarely been studied. Therefore, this study investigated soil's properties and phosphorus forms, as well as their relationship, in salinized soil after the application of different biological materials, including rice straw (RS), biochar (B), acidified biochar (AB), BM, RS+BM, B+BM, and AB+BM. A sequential extraction procedure was employed to determine the soil organic/inorganic phosphorus forms (Po/Pi). In our study, the contents of the soil's resin-P, NaHCO3-Pi, NaOH-Pi, and HCl-P increased by 50–341.66%, 4.08–184.63%, 37.45–163.45%, and 10.19–38.29%, respectively, with the application of the biological materials compared to with conventional fertilization (CK1). However, the contents of the soil's NaHCO3-Po, NaOH-Po, and residual-P significantly decreased in comparison to with CK1, particularly in the soils that received a combined application with biological materials and BM. Furthermore, the results from the statistical analysis revealed that the application of biological materials could increase the level of soil stable phosphorus, facilitate the transformation from soil stable phosphorus and soil unstable Po to soil unstable Pi, and enhance the effectiveness of soil phosphorus, especially when combined with BM, particularly in soil with AB+BM. [ABSTRACT FROM AUTHOR]

Species turnover with elevation is a widespread phenomenon and provides valuable information on why and how ecological communities might reorganize as the climate warms. It is commonly assumed that species interactions are more likely to set warm range limits, while physiological tolerances determine cold range limits. However, most studies are from temperate systems and rely on correlations between thermal physiological traits and range limits; little is known about how physiological traits and biotic interactions change simultaneously along continuous thermal gradients. We used a combination of correlational and experimental approaches to investigate communities of Drosophila flies in rainforests of the Australian Wet Tropics, where there is substantial species turnover with elevation. Our experiments quantified individual‐level and population‐level responses to temperature, as well as the impact of interspecific competition under different temperature regimes. Species' distributions were better explained by their performance at extreme temperatures than by their thermal optima. Upper thermal limits varied less among species than lower thermal limits. Nonetheless, these small differences were associated with differences in the centered elevation of distribution. Low‐elevation species were not those with the lowest tolerance to cold, suggesting that cold temperatures were not limiting their abundance at high elevations. Instead, under upland temperature regimes, abundances of these low‐elevation species were reduced by competition with a high‐elevation species, in both short‐ and long‐term competition experiments. Our results demonstrate that high‐elevation species are confined to their current ranges by high temperatures at lower elevations, indicating that their ranges will be highly sensitive to future warming. Counter to expectation, species interactions strongly influenced community composition at cooler, high‐elevation sites. Together, these results raise the possibility that tropical communities differ from better‐studied temperate communities in terms of the relative importance of biotic interactions and abiotic factors in shaping community composition and how the impact of these factors will change as temperatures increase. [ABSTRACT FROM AUTHOR]

Bismuth vanadate (BVO) is regarded as an exceptional photoanode material for photoelectrochemical (PEC) water splitting, but it is restricted by the severe photocorrosion and slow water oxidation kinetics. Herein, a synergistic strategy combined with a Co3(HPO4)2(OH)2 (CoPH) cocatalyst and an Al2O3 (ALO) passivation layer was proposed for enhanced PEC performance. The CoPH/ALO/BVO photoanode exhibits an impressive photocurrent density of 4.9 mA cm−2 at 1.23 VRHE and an applied bias photon-to-current efficiency (ABPE) of 1.47% at 0.76 VRHE. This outstanding PEC performance can be ascribed to the suppressed surface charge recombination, facilitated interfacial charge transfer, and accelerated water oxidation kinetics with the introduction of the CoPH cocatalyst and ALO passivation layer. This work provides a novel and synergistic approach to design an efficient and stable photoanode for PEC applications by combining an oxygen evolution cocatalyst and a passivation layer. [ABSTRACT FROM AUTHOR]

In view of the accident of main transformer being broken due to tower at incoming lines of Tunlan substation caused by lightning strike, the problems of lightning protection measures of the incoming lines were analyzed and researched. The research results show that the lightning protection of the incoming lines has problems such as excessive grounding resistance of the tower, too high lines insulation level, and mismatching between action value of arrester and lines insulation level. In view of the existing problems and hidden dangers, the following modification measures were proposed: optimize impulse grounding of the tower at incoming lines by using dendritic radioactive grounding body; use adjustable overvoltage protection gap to match lines arresters on the terminal tower, so as to form refined comprehensive protection of the incoming lines; install gap-free zinc oxide arrester on the terminal tower at incoming lines. The ATP-EMTP simulation results show that the combined effects of the three modification measures can effectively reduce amplitude and steepness of lightning intruding wave and ensure safe operation of the mine power grid.

In order to explore the influence of vegetation on homogeneity of surface particle size distribution (PSD) and heterogeneity of soil structure, observations, theory, and multifractal results were synthesized to highlight the evolution of the soil particle composition in the Jilantai Salt Lake Protection System (Jilantai system) after long‐term wind‐sand activities and its soil structure characteristics. From flowing sand dune to saline‐alkali wasteland areas, the mean grain size and surface particle sorting degree gradually increased and decreased, respectively, whereas the shape of the particle frequency curve gradually changed from extremely positive deviation to negative deviation, and the peak shape of the curve gradually changed from narrow to wide. Furthermore, the inhomogeneity of the soil particle composition gradually decreased, whereas the range of the soil PSD gradually increased, and the soil increasingly became fine‐grained. Therefore, the contents of clay and silt in shelterbelt soil increased by 16% and 18.36%, respectively, over 1986 levels. Additionally, clay and silt play a vital role in determining soil particle parameters such as standard deviation (SD), skewness (SKI), and monofractal (D), while vegetation factors are the main controlling factors of clay and silt. In conclusion, the Jilantai system could increase heterogeneity and homogeneity and decrease the concentration of soil PSD by changing the sedimentary environment, while this affect depends largely on the fractional vegetation cover, vegetation height, and light penetrating porosity. Moreover, the multifractal and particle parameters could describe the soil structure characteristics and sedimentary process, respectively, after long‐term wind‐sand activities. [ABSTRACT FROM AUTHOR]

As mean temperatures increase and heatwaves become more frequent, species are expanding their distributions to colonise new habitats. The resulting novel species interactions will simultaneously shape the temperature‐driven reorganization of resident communities. The interactive effects of climate change and climate change‐facilitated invasion have rarely been studied in multi‐trophic communities, and are likely to differ depending on the nature of the climatic driver (i.e., climate extremes or constant warming). We re‐created under laboratory conditions a host‐parasitoid community typical of high‐elevation rainforest sites in Queensland, Australia, comprising four Drosophila species and two associated parasitoid species. We subjected these communities to an equivalent increase in average temperature in the form of periodic heatwaves or constant warming, in combination with an invasion treatment involving a novel host species from lower‐elevation habitats. The two parasitoid species were sensitive to both warming and heatwaves, while the demographic responses of Drosophila species were highly idiosyncratic, reflecting the combined effects of thermal tolerance, parasitism, competition, and facilitation. After multiple generations, our heatwave treatment promoted the establishment of low‐elevation species in upland communities. Invasion of the low‐elevation species correlated negatively with the abundance of one of the parasitoid species, leading to cascading effects on its hosts and their competitors. Our study, therefore, reveals differing, sometimes contrasting, impacts of extreme temperatures and constant warming on community composition. It also highlights how the scale and direction of climate impacts could be further modified by invading species within a bi‐trophic community network. [ABSTRACT FROM AUTHOR]

The improvement effect of willow (Salix matsudana cv. zhuliu) cultivation on coastal saline soil and the main factors affecting soil properties were studied. Three treatments were designed: willow seeding site (SS), willow afforestation site (AS) and natural control site (CK). The results showed that soil pH and ECe decreased from 8.50 to 7.43 and from 6.8 dS/m to 0.8 dS/m at 0–20 cm layer, respectively. Willow cultivation significantly increased soil organic matter both in SS (3.64 g kg−1 – 4.05 g kg −1) and AS (2.82 g kg−1 – 3.92 g kg −1) treatments. The soil total nitrogen and available potassium of different treatments were increased with time and ranked AS > SS > CK. The AS16 treatment has a higher soil enzyme activity (soil urease, catalase, sucrase and phosphatase) and soil microbial population (bacteria, fungi and actinomycetes). Redundancy analysis suggested that soil pH and salinity were the key factors (85.4%) determining soil microbial quantities. Principal component analysis showed that the soil improvement by willow cultivation was significantly affected by soil enzyme activity, and AS16 had a better effect on costal saline soil especially in reducing soil salinity and improving microbial environment [ABSTRACT FROM AUTHOR]

Long-gap peripheral nerve injury remains a major challenge in regenerative medicine and results in permanent sensory and motor dysfunction. Nerve guidance scaffolds (NGSs) are known as a promising alternative to autologous nerve grafting. The latter, the current "gold standard" in clinical practice, is frequently constrained by the limited availability of sources and the inevitable damage to the donor area. Given the electrophysiological properties of nerves, electroactive biomaterials are being intensively investigated in nerve tissue engineering. In this study, we engineered a conductive NGS compounded of biodegradable waterborne polyurethane (WPU) and polydopamine-reduced graphene oxide (pGO) for repairing impaired peripheral nerves. The incorporation of pGO at the optimal concentration (3 wt%) promoted in vitro spreading of Schwann cells (SCs) with high expression of the proliferation marker S100 protein. In an in vivo study of sciatic nerve transection injury, WPU/pGO NGSs were found to regulate the immune microenvironment by activating macrophage M2 polarization and upregulate growth-associated protein 43 (GAP43) to facilitate axonal elongation. Histological and motor function analysis demonstrated that WPU/pGO NGSs had a neuroprosthetic effect close to that of an autograft, which significantly promoted the regeneration of myelinated axons, reduced gastrocnemius atrophy, and enhanced hindlimb motor function. These findings together suggested that electroactive WPU/pGO NGSs may represent a safe and effective strategy to manage large nerve defects. [ABSTRACT FROM AUTHOR]

Gas insulated switchgear (GIS) is widely used in the construction of State Grid Substations, and it is usually necessary to do insulation withstand voltage tests before GIS is put into production. To locate faulty equipment on site, according to the practical application environment, a fast and effective method was presented to locate the fault equipment in GIS insulation withstand voltage test by using distributed acoustic sensing (DAS) system. Through the back Rayleigh scattering signal of the optical fiber itself, the phase heterodyne was adopted phase-sensitive optical time-domain reflectometer (φ-OTDR) multi wavelength multi path modulation and demodulation method, which can visually and real-time monitor the optical fiber vibration signals at different positions of the metal shell of the GIS system to reduce the test blind spots. The experimental test results show that, fast and accurate positioning of fault equipment in GIS can be realized with the developed DAS system, and the positioning accuracy can reach within 3 m. It has a good reference value for timely troubleshooting and maintenance of GIS field faults and ensuring the safe operation of power equipment. [ABSTRACT FROM AUTHOR]

This study aims at developing novel methodology to prepare antibacterial cotton fabric with excellent antibacterial durability, and a "grafting through" approach was adopted to enhance affinity of Ag NPs with cotton fiber surfaces. The surface modification was carried out by covalently linking acrylic acid (AA) molecules onto the fibers, then 4‐vinylpyridine was copolymerized with the AA moieties as a polymeric binder. Once the coordination bonds were formed between silver nanoparticles (Ag NPs) and the pyridine nitrogen, Ag NPs could be stably immobilized on the cotton fabric. Experimental results showed that the AA‐co‐PVP grafting copolymer had a significant regulatory effect on the dispersion and particle size of Ag particles, and the resulting cotton fabric presented a high antibacterial property with excellent durability. Even after 120 washing cycles, the bacterial reduction rates of the modified fabric against both Staphylococcus aureus and Escherichia coli retained a level higher than 99%. In addition, other textile attributes, such as vapor transmissibility, water absorbability and flexibility, could be largely retained in the modified fabrics. [ABSTRACT FROM AUTHOR]

The paper introduced some basic situations of lightning protection measures of inlet line of a mining area 110 kV substation, analyzed causes of lightning strike of 35 kV inlet line of the substation, namely line insulation level increased by people is mismatch with on-site insulation level and inlet line tower grounding resistance is too high, and proposed corresponding renovation measures, namely adopting difference protection measures of installation of insulator protection gap with lightning arrester and dendritic grounding device.ATP-EMTP simulation results verify feasibility of the reform measures.

In view of present status that current coal mine gas drainage station using independent lightning rod for direct lightning stroke protection, problems and hidden troubles of the status were analyzed, and a new type of lightning protection and grounding method was proposed. The method uses lightning protection framework and upper lightning protection network to replace lightning rod for the direct lightning stroke protection, uses sideward lightning shield wire against shielding failure for lightning shielding failure protection. Meanwhile, it introduces grounding device outside the station, so as to keep a certain safety distance from the grounding device to flammable and explosive materials inside the station. The actual application result shows the method has good lightning protection effect, and also has reference value for direct lightning protection and grounding of oil deport, gas station and other flammable and explosive place.

The physical and chemical properties of tissue engineering scaffolds have considerable effects on the inflammatory response at the implant site in soft tissue repair. The development of inflammation-modulating polymer scaffolds for soft tissue repair is attracting increasing attention. In this study, in order to regulate the inflammatory response at the implant site, a series of waterborne polyurethane (WPU) scaffolds with different properties were synthesized using polyethylene glycol (PEG), polycaprolactone (PCL) and poly (lactic acid)–glycolic acid copolymers (PLGAs) with three lactic acid/glycolic acid (LA/GA) ratios as the soft segments. Then, scaffolds were obtained using freeze-drying. The WPU scaffolds exhibited a porous cellular structure, high porosity, proper mechanical properties for repairing nerve tissue and an adjustable degradation rate. In vitro cellular experiments showed that the degradation solution possessed high biocompatibility. The in vitro inflammatory response of C57BL/6 mouse brain microglia (immortalized) (BV2) cells demonstrated that the LA/GA ratio of the PLGA in WPU scaffolds can regulate the external inflammatory response by altering the secretion of IL-10 and TNF-α. Even the IL-10/TNF-α of PU5050 (3.64) reached 69 times that of the control group (0.053). The results of the PC12 culture on the scaffolds showed that the scaffolds had positive effects on the growth, proliferation and differentiation of nerve cells and could even promote the formation of synapses. Overall, these scaffolds, particularly the PU5050, indeed prevent BV2 cells from differentiating into a pro-inflammatory M1 phenotype, which makes them promising candidates for reducing the inflammatory response and repairing nerve tissue. Furthermore, PU5050 had the best effect on preventing the transformation of BV2 cells into the pro-inflammatory M1 phenotype. [ABSTRACT FROM AUTHOR]

Decellularized extracellular matrix (dECM) nerve guide conduits (NGCs) are a promising strategy to replace autogenous nerve grafting for the treatment of peripheral nerve system (PNS) injury. However, dECM conduits with mechanical properties that match those of peripheral nerves are yet to be well developed. Herein, we developed polyurethane-based NGCs incorporating decellularized spinal cord (BWPU-DSC NGCs) to repair peripheral nerves. BWPU-DSC NGCs have an inner three-dimensional micro–nanostructure. The mechanical properties of BWPU-DSC NGCs were similar to those of polyurethane NGCs, which were proven to promote peripheral nerve regeneration. An in vitro study indicated that BWPU-DSC NGCs could boost the proliferation and growth of cell processes in Schwann and neuron-like cells. In a rat sciatic nerve transected injury model, BWPU-DSC NGCs exhibited a dramatic increase in nerve repair, similar to that obtained by the current gold standard autograft implantation at only 6 weeks post-implantation, whereas polyurethane NGCs still displayed incomplete nerve repair. Histological analysis revealed that BWPU-DSC NGCs could induce the reprogramming of Schwann cells to promote axon regeneration and remyelination. Moreover, reprogrammed Schwann cells together with BWPU-DSC NGCs had anti-inflammatory effects and altered the activation state of macrophages to M2 phenotypes to enhance PNS regeneration. In this study, we provided a strategy to prepare polyurethane-based dECM NGCs enriched with bioactive molecules to promote PNS regeneration. [ABSTRACT FROM AUTHOR]

Salt-affected soils frequently experience leaching and desalination issues, which severely restrict plant growth and water uptake. Hence, in this experiment, four treatments including CG (no amendments addition); OF (organic fertilizer addition); OH (organic fertilizer and Hekang amendment addition); and OB (organic fertilizer and fulvic acid addition) were designed to examine the effect of organic amendment on soil chemical properties, water and salt transport, and soil desalination laws of coastal saline soil. The results showed that the addition of organic amendments significantly reduced soil pH (8.47–8.52) and salt content (2.06–2.34 g kg−1), while increasing soil organic matter content, available phosphorus, and available potassium. OH treatment has a higher available phosphorus content than other treatments. OH and OB treatments elevated the soil desalination ratio (32.95% and 32.12%, respectively) by raising the leaching volume and leaching rate. Organic amendments significantly promoted Na+ (4.5–32%) and SO42− (12–27%) leaching compared to CG. Organic treatments, particularly OB treatment, not only increased the content of soil organic matter and available nutrients but also promoted salt ion leaching, improved soil permeability and increased soil desalination and water leaching rates. Our results may provide a theoretical basis for revealing the desalination law of coastal saline soil. [ABSTRACT FROM AUTHOR]

Summary: Multi‐robot systems are widely used to handle complex and cooperative missions in various industrial applications. Although robotic middleware has become the key to reducing the complexity of multi‐robot application development, existing works still have limitations in controlling multiple robots to perform missions cooperatively. To enable multi‐robot cooperation, middleware should provide high‐level abstraction support, dynamic configuration, communication, and synchronization. In this article, we propose GraphWare, a novel middleware that provides a graph‐based programming abstraction and its underlying runtime kernel for programming and building multi‐robot cooperation applications. The graph‐based programming abstraction can express cooperative missions without exposing the complexity of managing multiple robots. The runtime kernel configures and manages multiple heterogeneous robots to intelligently perform cooperative missions. We implement GraphWare and evaluate its performance with ball collection missions which are cooperatively accomplished by a group of mobile robots, and study the fault‐tolerance, flexibility, and scalability of the middleware in the realistic simulation. The experimental results demonstrate that GraphWare facilitates the multi‐robot cooperative mission with efficient mission completion time, high success rate, and marginal runtime overhead. [ABSTRACT FROM AUTHOR]

This paper proposes a novel image encryption algorithm based on an integer form of chaotic mapping and 2-order bit compass diffusion technique. Chaotic mapping has been widely used in image encryption. If the floating-point number generated by chaotic mapping is applied to image encryption algorithm, it will slow encryption and increase the difficulty of hardware implementation. An innovative pseudo-random integer sequence generator is proposed. In chaotic system, the result of one-iteration is used as the shift value of two binary sequences, the original symmetry relationship is changed, and then XOR operation is performed to generate a new binary sequence. Multiple iterations can generate pseudo-random integer sequences. Here integer sequences have been used in scrambling of pixel positions. Meanwhile, this paper demonstrates that there is an inverse operation in the XOR operation of two binary sequences. A new pixel diffusion technique based on bit compass coding is proposed. The key vector of the algorithm comes from the original image and is hidden by image encryption. The efficiency of our proposed method in encrypting a large number of images is evaluated using security analysis and time complexity. The performance evaluation of algorithm includes key space, histogram differential attacks, gray value distribution(GDV),correlation coefficient, PSNR, entropy, and sensitivity. The comparison between the results of coefficient, entropy, PSNR, GDV, and time complexity further proves the effectiveness of the algorithm. [ABSTRACT FROM AUTHOR]