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• All port cities experienced dramatic growth in artificial surfaces in 2000–2020. • We identified the coordination of urbanization-vegetation cover in port cities. • Overall coordination of urbanization-vegetation cover improved in port cities. • Coordination changes varied across cities at different economic levels. • Identifying coordination relationships to promote sustainable development in port cities. The sustainability of port cities affects the competitiveness of their hinterland in international shipping and maritime trade, however, the coordinated relationship between urbanization and ecological environment in port cities has received less attention. In this study, we quantitatively analyzed the urban expansion process and vegetation cover changes in 44 port cities along the Maritime Silk Road during 2000–2020 based on multi-source remote sensing data. Adopting the urbanization-vegetation cover index (UVCI), we measured the coordination relationship between urban expansion and vegetation cover and the dynamics during 2000–2020. The results found that all port cities experienced dramatic development from 2000 to 2020, with an average increase in artificial surface area of 127.81%. The 63.64% of port cities experienced increased vegetation cover, thus the overall UVCI in the port city moved toward a more coordinated and sustainable pattern with significant heterogeneity at the economic levels. High-economy port cities have generally become more coordinated, while most low- and medium-economy cities still face challenges of conflicting urban expansion and ecological preservation. This study contributes to the development of government policies that support green and sustainable urban development in port cities, and provides insights for rationalizing development policies in port cities worldwide. [ABSTRACT FROM AUTHOR]

Thermal contact resistance is a crucial parameter for the thermal management of electronic devices, as it directly impacts the heat dissipation efficiency across densely packed component interfaces. This paper proposes a finite element modeling approach to predict thermal contact resistance. The model is based on the optically measured surface topography of Al6061 alloy pairs using a white light interferometer. A mechanical-thermal sequential coupling approach is developed to simulate the contact area and temperature distribution of the contact model. Elastic-plastic deformable mechanics and interface heat transfer in terms of spots and gap conduction are incorporated into the approach. The research indicates that the pressure between longitudinal surfaces significantly influences heat transfer preceding the solid contact point. At an upper surface load pressure of 0.15 MPa, the thermal contact resistance is 329 mm²·K/W. With a gradual increase in load up to 0.6 MPa, the thermal resistance decreases to 244 mm²·K/W. Moreover, the transition of interstitial gas from free molecules to a continuous state results in decreased thermal conductivity. Specifically, at gas pressures of 5 Pa and 1 atm, the thermal contact resistance reduces from 557 mm²·K/W to 270 mm²·K/W. Furthermore, the numerical results, when compared to experimental data under different gas pressures, exhibit a discrepancy of less than 15%. This outcome effectively validates the accuracy of the proposed method. [ABSTRACT FROM AUTHOR]

Long-term soil chronosequences are valuable model systems for investigating pedogenesis and investigating the process of element coupling. Here, we assessed the coupling relationships among C, Fe, and Fe-reducing bacteria (Anaeromyxobacter, Geobacter, and Shewanella) in a paddy soil chronosequence of approximately 50 to 1000 years. Soils of the chronosequence originated from tidal marsh under nearly identical landscape and climate conditions. During 1000 years of rice cultivation, soil organic carbon (SOC) contents in surface horizons (0–20 cm) increased from 10.4 to 21.8 g kg−1. In contrast, total Fe contents declined from 59.6 to 45.1 g kg−1 during the initial 50 years of paddy rice cultivation and then further decreased at a low rate of 0.004 g kg−1 soil year−1 (equivalent to 10 kg ha−1 soil year−1). Organically complexed Fe oxides (Fep) increased from 219 to 642 mg g−1 with increasing time of pedogenesis, but free total Fe oxides (Fed) and amorphous Fe oxides (Feo) declined at early stage of soil development, followed by a slow accumulation at later stages of the chronosequence. Gene copy numbers of Anaeromyxobacter and Geobacter increased from 4.6 × 105 and 3.6 × 106 copies g−1 to 3.8 × 107 and 3.6 × 107 copies g−1 dry soil with continuous paddy rice cultivation, while concurrently Shewanella gene abundance decreased gradually from 4.5 × 105 to 9.3 × 104 copies g−1 dry soil. Using structural equation modeling (SEM), different coupling relationships were observed among C, Fe, and Fe-reducing bacteria for the first 300 years of paddy chronosequence and thereafter. Overall, all Fe-reducing bacteria did not show consistent variation. With the stable microbial community and iron oxide fractions, the microbially mediated dissimilatory coupling relationship between C and Fe becomes simple during 1000 years of paddy soil development. [ABSTRACT FROM AUTHOR]

Highlights • A novel dynamic evaluation system is proposed for monitoring urban ambient air condition. • The enhanced sine cosine algorithm is proposed to tune the parameters of forecast engine. • The fuzzy synthetic evaluation model with entropy weight is used to perform the air quality levels. • Three real data examples are conducted to investigate the proposed monitoring system. Abstract Accurate real-time prediction of urban air quality is one of the most important problems in control and improve ambient air condition globally. Therefore, the modeling and applications of air pollutant forecasting and evaluation has attracted the attention of researchers in recent years. Based on the method of fuzzy mathematical synthetic evaluation, this paper built a dynamic evaluation model for the purpose of mastering the future air quality immediately. A newly proposed computational intelligence optimization algorithm is improved to optimize the least square support vector machine, which can generate rolling forecasts of six air pollutants concentration. The information of future air quality status is built by the fuzzy synthetic assessment model based on entropy weighing method. The results and analysis of air quality monitoring show that accurate and reliable forecast of urban air pollutants concentration are possible and the air quality conditions can be evaluated objectively. Through the simulation design, it proves that the proposed dynamic evaluation model can provide a practical tool for ambient air ambient quality evaluation. [ABSTRACT FROM AUTHOR]

Wave energy forecasting modeling is critical for promoting renewable energy storage technology as well as for energy sustainability and global carbon neutrality goals. However, due to the irregular volatility and complexity in wave energy data, all the effective information cannot be fully utilized by a traditional forecasting model; moreover, the point forecasting results cannot be used to effectively analyze the uncertainty of the time series. To overcome these shortcomings, a multistep point-interval combined significant wave height forecasting system based on the multiobjective grasshopper optimization algorithm and the fuzzy information granulation strategy is proposed to forecast the half-hour actual wave height at different buoy locations. Applying this system, Pareto optimal weights can be obtained to integrate the respective advantages of deep learning and neural network models in the combined forecasting module, achieve the best point and interval forecasting accuracy and accurately analyze the uncertainty of point forecasting results. Among the combined models, the proposed system has a more comprehensive and scientific prediction performance than other models (MAPE = 4.9866 for Site 1, MAPE = 4.9138 for Site 2, and MAPE = 3.9572 for Site 3). The forecasting outcomes indicate that the developed system significantly improves forecasting accuracy and stability, which provides reliable technical support for the sustainable development of wave power generation. [ABSTRACT FROM AUTHOR]

Encouraged by the successful fabrication of C60‐GNR (GNR=graphene nanoribbon) single‐molecule transistors in experiments, four Fe‐containing derived double‐layered devices of Fe@C60‐GNR are designed by employing different electrode linkages and their transport properties are investigated by using density functional theory (DFT) and nonequilibrium Green's function (NEGF) methods. Regardless of electrode connection, all these devices give rise to a smaller negative differential resistance (NDR) peak at V=0.2 and a higher peak at 1.2 V, suggesting their stable maneuverability as molecular devices and good candidates for developing on(off)‐off(on)‐on(off) current switches. The macroscopic NDR performance depends on the delocalization character and the crossing mechanism of the frontier orbitals. The peak‐to‐valley current ratios (Rmax) range from 454 to 2737, determined by the electrode linkage. Such a large Rmax‐value is necessary for developing dynamic random‐access memory (DRAM) cells. Encapsulating the Fe atom inside C60 not only improves the conductivity but also introduces the spin‐polarized transport property. The spin‐filtering efficiency (SFE) of almost all devices oscillates up and down in response to the bias voltage, indicating the possibility of designing on(off)‐off(on)‐on(off) spin switches and up‐down spin switches. All these fascinating properties provide an important clue for designing similar molecular devices with multiple functions by trapping magnetic transition metal atoms inside fullerenes. [ABSTRACT FROM AUTHOR]

Encouraged by the promising performance of C60-graphene single-molecule transistors observed in experiments, two types of Fen/C60-GNR (n = 2 and 4 and GNR = graphene nanoribbon) molecules with Fe atoms sandwiched between the upper and lower GNR layers were designed and their electronic and transport properties were investigated by employing density functional theory (DFT) and nonequilibrium Green's function (NEGF) methods. Adding the Fe atoms induces high spin magnetism in the systems. Within the considered bias, almost all Fe2/C60-GNR devices generate double NDR peaks, and some of the Fen/C60-GNR devices (n = 2 and 4) possess a large peak-to-valley current ratio R = Ipeak/Ivalley (>400), implying potential applications in developing on–off–on/off–on–off current switches. The NDR character originates from the crossing of the frontier molecular orbitals. In addition, these systems show distinct spin-polarized transport characteristics, with up-spin channels displaying higher conductivity than down-spin pathways. The spin filter efficiency (SFE) oscillates up and down as bias is scanned for almost all devices, suggesting the possibility of designing on–off–on/off–on–off current switches as well as up–down spin switches. All these findings provide guidance for exploring single molecular devices with promising properties combined with graphene, fullerenes, and transition metals. [ABSTRACT FROM AUTHOR]

As a predominant ecosystem-providing area and distinctive landscape in arid regions, an oasis plays an important role in maintaining land stability, human production, and daily activities. Studying the dynamics of oasis and its driving factors is vital to supporting arid regions' sustainable development. As a typical mountain–desert–oasis landscape, the Turpan–Hami (Tuha) Basin, located in Xinjiang, China, includes complex interactions among different land types. For this study, we revealed the spatio-temporal patterns and transition processes of the oasis using a complex network method between 1990 and 2020 in the Tuha Basin. In the oasis transition network, the degree value, betweenness centrality, and average path length were calculated to express the transition relationship, key oasis type, and oasis structural stability, respectively. Six factors related to climate change and human actives were selected to investigate the driving forces behind oasis transitions, including the average temperature and precipitation in the growing season, the total power of agricultural machinery (TAMP), the production of raw coal (PRC), the total output value of the plantation industry (TPI), and the population (Pop). Our results show that the oasis area of the Tuha Basin, including the natural oasis and artificial oasis, all grew from 1990 to 2020, with the natural oasis expanding more than the artificial oasis. The transitions between oasis types became more frequent as the area of oasis land types increased throughout the study period. Grassland acted as the most important oasis type in the network, with the highest betweenness centrality, but its importance declined due to the increasing complexity of the oasis transition network from 1990 to 2020. The transitions between oasis types became simpler, and the oasis structural stability decreased. Through driving force analysis, the oasis changes showed a positive correlation with the temperature (p-value < 0.05, r = 0.88), and urbanization and industrialization factors prompted transitions to built-up areas and cropland from grassland and shrubland. In summary, our results suggest that to create a harmonious symbiotic relationship between the natural environment in dryland and human activities, preventing grassland degradation and excessive reclamation of land cover is an available way. Meanwhile, the protection of shrubland and water resources is also important. This study provided reference and theory support for promoting the sustainable development of oases. [ABSTRACT FROM AUTHOR]

Bi2MoO6 was one of the important bismuth-based semiconductors with a narrow bandgap, and has been widely used in selective oxidation catalysts, supercapacitors, and energy-storage devices. A series of Bi2MoO6/ZnO composite photocatalysts with different mass ratios were synthesized by the hydrothermal method. The synthesized samples were characterized by XRD, PL, UV-Vis, SEM, TEM, XPS, and BET analysis techniques. Under visible light conditions, Methylene blue (MB) was used as the target degradation product to evaluate its photocatalytic performance. The results showed that the degradation rate constant of Bi2MoO6/ZnO (0.4-BZO) was about twice that of the traditional photocatalysis of ZnO. The Bi2MoO6/ZnO composite catalyst maintained stable performance after four consecutive runs. The high photocatalytic activity of Bi2MoO6/ZnO was attributed to the efficient electron transport of the heterojunction, which accelerates the separation of electron-hole pairs and reduces the probability of carrier recombination near the Bi2MoO6/ZnO heterojunction. Bi2MoO6/ZnO nanocomposites have potential applications in the field of photodegradation. [ABSTRACT FROM AUTHOR]

The monkeypox virus (MPXV) is a linear double-stranded DNA virus with a large genome that causes tens of thousands of infections and hundreds of deaths in at least 40 countries and regions worldwide. Therefore, timely and accurate diagnostic testing could be an important measure to prevent the ongoing spread of MPXV and widespread epidemics. Here, we designed multiple sets of primers for the target region of MPXV for loop-mediated isothermal amplification (LAMP) detection and identified the optimal primer set. Then, the specificity in fluorescent LAMP detection was verified using the plasmids containing the target gene, pseudovirus and other DNA/RNA viruses. We also evaluated the sensitivity of the colorimetric LAMP detection system using the plasmid and pseudovirus samples, respectively. Besides, we used monkeypox pseudovirus to simulate real samples for detection. Subsequent to the establishment and introduction of a magnetic beads (MBs)-based nucleic acid extraction technique, an integrated device was developed, characterized by rapidity, high sensitivity, and remarkable specificity. This portable system demonstrated a visual detection limit of 137 copies/mL, achieving sample-to-answer detection within 1 h. The device has the advantages of integration, simplicity, miniaturization, and visualization, which help promote the realization of accurate, rapid, portable, and low-cost testing. Meanwhile, this platform could facilitate efficient, cost-effective and easy-operable point-of-care testing (POCT) in diverse resource-limited settings in addition to the laboratory. Fig. Schematic diagram of the integrated assay device. The integrated sample-to-answer device was fabricated with three modules, including nucleic acid extraction, LAMP reaction, and colorimetric readout. [Display omitted] • An integrated visual nucleic acid self-testing device based on LAMP assay. • Efficient enrichment of nucleic acids using Si-OH magnetic beads without elution. • Visual results can be obtained within 1 h using the sample-to-answer device. • The LOD for monkeypox virus nucleic acid is as low as 137 copies/mL. • The LAMP-based self-testing device is suitable for point-of-care testing. [ABSTRACT FROM AUTHOR]

Refractory high entropy alloys (RHEAs) with single-phase structure hold far great potential in the field of surface protection application under extreme environment such as high temperature, abrasion and corrosion. In this work, the effects of Cr, Zr and W on the microstructure evolution and properties of a single-phase body-centered-cubic (BCC) NbTaTiV RHEA coating have been investigated. Experimentally, in addition to a small amount of Laves phase introduced by Cr element, NbTaTiV-(Cr, Zr, W) RHEA coatings basically maintain the single BCC structure. The addition of different elements affects segregation degrees in dendrite microstructure, and Zr shows nanoscale chemical heterogeneity. Notably, grain refinement, elevated geometrically necessary dislocation density and high-density low angle grain boundaries lead to a dramatically increase of micro-hardness due to elements addition. The wear rate of NbTaTiVCr and NbTaTiVW RHEA coatings reduce by 74.98 % and 70.79 % compared with NbTaTiV coating. The wide passive passivation zones close to 1000 mV obtained by potentiodynamic polarization exhibit excellent corrosion resistance. In addition, the formation mechanism of oxide layers is studied by thermodynamic parameters and oxidation behavior of simple oxides. The current work provides theoretical support for the application of strengthening elements in a single-phase BCC RHEA coating. [Display omitted] • Lattice distortion of BCC phase after adding elements is affected to various degrees. • There exists nanoscale chemical heterogeneity in NbTaTiVZr RHEA coating. • The interaction between different types of grain boundaries and dislocations enhances hardness of RHEA coatings. • The wide passive passivation zones close to 1000 mV are exhibited in potentiodynamic polarization curves. • The thermodynamic parameters and oxidation behavior of simple oxides determine the formation of oxide layers. [ABSTRACT FROM AUTHOR]

• Subsoiling managements improved soil microstructure in the whole soil profile. • Subsoiling with straw favored microbial growth and SOC sequestration in the whole soil profile. • Bacteria and macropore porosity mainly drive the variation in topsoil C within aggregates. • Bacteria and micropore porosity mainly drive the variation in subsoil C within aggregates. • Microbe contributed more to regulate SOC than soil microstructure did. Soil organic carbon (SOC) accumulation is easily susceptible to tillage managements, which strongly affect soil structure and microbial community structure. Subsoiling is developed for mitigating soil compaction and thus improving soil structure. Coupled with straw residue incorporation, it is expected not only to enhance this improvement but also to promote organic carbon (C) storage in soil. However, how subsoiling tillage managements change soil aggregate microstructure, microbial community structure and SOC fractions, and how soil aggregate microstructure and microbial community structure affect SOC in the topsoil and subsoil layers are equally unknown. An in-situ incubation field experiment was conducted in a Mollisol in northeastern China and included conventional tillage (CT), subsoiling tillage (ST) and subsoiling tillage with straw residue incorporation (ST + S). The methods of synchrotron-based X-ray micro-computed tomography scanning, phospholipid fatty acid and SOC density fractionation were used to analyze aggregate pore characteristics, microbial community structure and SOC fractions, respectively. The results showed that both ST and especially ST + S not only improved soil aggregate microstructure but also enhanced microbial biomass and then favored SOC accrual in the topsoil (0–20 cm). In the subsoil (20–35 cm), ST + S exerted similar positive effects as those in the topsoil. However, ST only improved soil aggregate microstructure but decreased microbial community biomass and SOC in the subsoil. Moreover, soil aggregate structure characteristics explained (solely explained 6 % in the topsoil and 12 % in the subsoil, respectively) a smaller part of the variation in SOC within aggregates than soil microbial characteristics did (solely explained 15 % in the topsoil and 25 % in the subsoil, respectively). Specifically, bacteria explained 26 % and 66 % of the variation in SOC within aggregates in the topsoil and subsoil, respectively. The porosity of macropores (>100 μm) also explained 25 % of the variation in SOC within aggregates in the topsoil, whereas the porosity of micropores (<30 μm) explained more variation (12 %) than that of macropores (3 %) in the subsoil. Notably, the substantially different interaction mechanism-processed of pore characteristics, microbial structure and SOC between topsoil and subsoil was probably traceable for the variation in the influx of organic C, pore size distribution and microbial adaptability in soil layers. These results would provide new insights on tillage managements strategies for improving soil conditions in terms of optimizing soil aggregate microstructure–microbes–SOC interactions in the topsoil and subsoil layers. [ABSTRACT FROM AUTHOR]

[Display omitted] • PLA/gel/ZnO nanofiber aerogel scaffolds with three-dimensional nanofibrous structure were developed. • PLA/gel/ZnO nanofiber aerogel scaffolds exhibited good antibacterial properties. • PLA/gel/ZnO nanofiber aerogel scaffolds could decrease inflammatory reactions and promote angiogenesis. • PLA/gel/ZnO nanofiber aerogel scaffolds significantly accelerated the wound healing process. Bacterial infection and severe wound inflammation are two primary harmful problems that bring harm to the human body and may cause death when a large-scale skin defect occurs. Thus, developing an effective and quick wound healing strategy for curing skin damage and trauma is vital. This study has developed a multifunctional PLA/gelatin/ZnO nanofiber aerogel with a three-dimensional structure through electrospinning and freeze-drying technology for wound healing. It has validated that the nanofiber aerogel has an excellent antibacterial property and biocompatibility. Meanwhile, benefiting from its three-dimensional nanofiber structure, the PLA/gelatin/ZnO nanofiber aerogel possesses good water absorption and air permeability. In vivo experiments have determined that the PLA/gel/ZnO nanofiber aerogel scaffolds effectively promote skin infection's wound healing and enhance angiogenesis that is practical with increasing ZnO concentration. [ABSTRACT FROM AUTHOR]

• Phage vB_ValP_IME234 is a novel virulent phage belonging to the podoviridae family, which can infect both V. alginolyticus and vibrio parahaemolyticus. • No integrase gene was detected, suggesting the phage is not temperate — which is important for application. • There were lysis genes and no antibiotic resistance or potential virulence genes in phage vB_ValP_IME234 genome, so this phage may serve as potential agents for phage therapy. Bacterial infections have a negative impact on both animal husbandry industry and medicine, and increasing bacterial drug resistance exacerbates this adverse impact. Phages show promise as an alternative to drugs against drug-resistant bacteria. In this study, a novel virulent bacteriophage (phage) vB_ValP_IME234 against Vibrio alginolyticus and Vibrio parahaemolyticus was isolated from freshwater in Beijing, China. Phage vB_ValP_IME234 had an isometric head (59 nm in diameter) and a short tail (10 nm long), belonging to Podoviridae family. Its complete genome is liner double-stranded DNA (dsDNA) with a GC content of 41.6% while encoding 61 putative proteins. Three transfer RNA (tRNA) and no lysogenic gene was detected. vB_ValP_IME234 had a polyvalent infectivity, a burst of 390 PFU/cell, and is stable under different temperatures (4 °C to 50 °C) and pH (6.0 to 10.0) values. Host range test showed that vB_ValP_IME234 has the ability to infect seven strains of Vibrio in total. Phylogenetic analyses based on terminase and capsid suggested that this phage had a close relationship with Vibrio phages. These results indicate that vB_ValP_IME234 could be used as a potential biocontrol agent against V. alginolyticus strains. [ABSTRACT FROM AUTHOR]

Abstract: In this work, the plasma sprayed wollastonite coating was soaked in 5wt% AgNO3 solution at room temperature to load silver for improving its antibacterial effect. The surface characteristics of the silver-loaded coating were investigated by SEM, EDS and XRD. The release rate of silver from the coating was measured by ICP-OES in deionized water. The osteotoxicity of the silver-loaded coating was evaluated by in vitro cell culturing test. The antibacterial activity against Staphylococcus aureus was examined by Zone of Inhibition test. The results showed that the loaded silver reacted with the wollastonite coating to form silver silicate, which ensured a sustained release of silver in deionized water for as long as 50 days. The antibacterial activity and cell culturing tests confirmed that the silver released from silver-loaded wollastonite coating had strong inhibition against the growth of S. aureus, while they did not exhibit any adverse effects on the osteoblasts proliferation. [Copyright &y& Elsevier]