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Fabrication of versatile hydrogels in a facile and effective manner represents a pivotal challenge in the field of biomaterials. Herein, a novel strategy is presented for preparing on‐demand degradable hydrogels with multilevel responsiveness. By employing selenol‐dichlorotetrazine nucleophilic aromatic substitution (SNAr) to synthesize hydrogels under mild conditions in a buffer solution, the necessity of additives or posttreatments can be obviated. The nucleophilic and redox reactions between selenol and tetrazine culminate in the formation of three degradable chemical bonds—diselenide, aryl selenide, and dearomatized selenide—in a single, expeditious step. The resultant hydrogel manifests exceptional adaptability to intricate environments in conjunction with self‐healing and on‐demand degradation properties. Furthermore, the resulting material demonstrated light‐triggered antibacterial activity. Animal studies further underscore the potential of integrating metformin into Se‐Tz hydrogels under green light irradiation, as it effectively stimulates angiogenesis and collagen deposition, thereby fostering efficient wound healing. In comparison to previously documented hydrogels, Se‐Tz hydrogels exhibit controlled degradation and drug release, outstanding antibacterial activity, mechanical robustness, and bioactivity, all without the need for costly and intricate preparation procedures. These findings underscore Se‐Tz hydrogels as a safe and effective therapeutic option for diabetic wound dressings. [ABSTRACT FROM AUTHOR]

Patients who undergo resection for melanoma face challenges, such as delayed healing and radiation dermatitis. Moreover, incomplete tumor resection is a key factor contributing to poor prognosis and increased recurrence rates. However, a therapeutic platform that can effectively prevent tumor recurrence and promote wound healing remains a challenge. Hence, a pioneering approach is presented using melanoma‐derived cancer cell membrane (CM) as a tumor antigen to encapsulate copper (Cu)‐based metal‐organic framework (MOF) nanomaterials to fabricate nanomaterials termed MOF@CM. Then MOF@CM is adsorbed onto polydopamine (PDA)‐modified poly lactic‐co‐glycolic acid (PLGA) porous microspheres (PLGA/PDA) to develop the copper nanomaterials‐decorated microspheres termed PLGA/PDA‐CCM (PLGA/PDA loaded with CM‐coated MOF). It exerts homologous tumor targeting and photothermal effects, inducing immunogenic cell death. Simultaneously, the sustained release of MOF@CM shows enhanced antigen presentation in dendritic cells (DCs) with the help of CpG, and induces DC maturation and activated immune responses, acting as an effective vaccine to prevent tumor recurrence. The platform harnesses the combined advantages of the local thermal effect and the presence of a Cu‐based MOF, which endow antibacterial properties and stimulate angiogenesis, thereby facilitating wound healing and mitigating radiation dermatitis. This integrated microsphere treatment platform represents a promising strategy for addressing melanoma. [ABSTRACT FROM AUTHOR]

Objective: To construct a hollow copper sulfide nano-enzyme lipid composite nanocarrier CuS@LIP, and to further investigate the effect and mechanism of CuS@LIP combined laser irradiation on killing melanoma B6-F10 cells. Methods: (2, 3-dioleoyloxy-propyl) -3-trimethylammonium-propane (chloride salt) (DOTAP) cationic liposomes (LIPs) were applied to encapsulate copper sulfide (CuS) to construct cationic liposome-coated copper sulfide nanocarriers (CuS@LIP). The photothermal properties and stability of CuS and CuS@LIP at different concentrations were studied under 1 064 nm laser irradiation. The peroxidase-like activity of CuS@LIP was verified by a catalytic activity detecting system of hydrogen peroxide (H2O2) and 3, 3', 5, 5' -tetramethylbenzidine (TMB). B16-F10 cells were treated respectively with a series of mass concentration gradients of CuS or CuS@LIP with or without laser. The cell viability of B16-F10 cells was determined via CCK-8 assay. Calcein-AM/PI staining and Annexin V-FITC/PI staining combined with flow cytometry detected the effects of 20 μg/mL CuS or CuS@LIP on the cell viability and apoptosis of B16-F10 cells under laser or non-laser irradiation, respectively. Results: The average particle size of successfully prepared CuS@LIP was (178.23±6.46) nm and the average Zeta potential was (20.47±0.93) mV. The highest temperature of 80 μg/mL CuS@LIP under laser irradiation was 65.4 °C, which was higher than that of CuS at 63.4 °C. The endpoint temperature of CuS@LIP was basically unchanged through the cyclic test of three laser on/off switches. In addition, CuS@LIP had the same peroxidase-like catalytic activity as CuS. CuS@LIP had no significant effect on the proliferation activity of B16-F10 cells in vitro when it was less than 20 μg/mL (P>0.05), but the survival rate was significantly reduced by 58.18% after laser irradiation ([29.76±3.60]% vs [87.95±8.18]%, P<0.000 1). The apoptosis rate was significantly increased ([19.34±4.41]% vs [13.36±0.86]%, P<0.01). Conclusion: The prepared CuS@LIP has physical and chemical properties, good photothermal properties and excellent peroxidase-like catalytic activity that meet the design requirements, and it shows a better effect of killing B16-F10 cells when combined with laser irradiation. [ABSTRACT FROM AUTHOR]

Although there seems to be a widely shared expectation that polycentricity increases economic competitiveness, the empirical findings are inconsistent. As the first meta-analysis, this paper examines whether emerging empirical evidence provides an insight into the polycentricity–productivity effect. Based on 139 estimates, we find no compelling evidence to support that polycentricity is either beneficial or detrimental for economic development. Further meta-logit regressions show that the measurement of polycentricity and the control of agglomeration economies indeed affect the polycentricity–productivity effect. In contrast, measuring polycentricity from different perspectives and the potential endogeneity do not appear to significantly influence this effect. [ABSTRACT FROM AUTHOR]

Polycentric planning strategies have often failed to achieve the expected effects. The ensuing uncertainty associated with the desirability of polycentric strategies is also reflected in the early literature which offers no clear conclusion about whether the polycentricity affects economic performance and how. This paper aims at offering a clear conclusion about it, especially its dependence on city size. Against this backdrop, we conceptualize polycentricity as a process of reclustering after decentralization to reevaluate its impact on performance. To this end, we use the city proper level Chinese Economic Census (2004, 2008, and 2013) and apply a fixed-effects panel model, the results of which show that the dependence of the urban economy on spatial structure is contingent on city size. More specifically, both decentralization and clustering (and therefore the polycentric structure) facilitate economic performance only when cities reach a certain size. We use our findings as the basis for outlining an emergent research agenda for urban polycentricity. [ABSTRACT FROM AUTHOR]

Light-emitting lead halide perovskite materials have attracted great attention due to their excellent optoelectrical properties. However, the combination of perovskites and conjugated polymers forming an exciplex has not been reported due to the limitations of fabrication. In this work, we introduce a strategy by using an ultraviolet (UV)-polymerizable acrylic monomer to fabricate perovskite–polymer composite films in the polymer matrix. Significantly, we systematically examined the exciton dynamics in composite films by time resolved photoluminescence and transient absorption spectra. We observed the formation of an exciplex and the emission from it. The energy levels and exciton dynamics of perovskite light-emitting polymers in the composite is proved to be influenced by the photopolymer matrix and the energy levels in the polymer matrix make the charge transfer and exciplex formation feasible. Furthermore, light-emitting devices were fabricated using the composite materials as phosphors on a 395 nm UV chip. The devices illustrate excellent water-repellent properties, which can work in an aqueous atmosphere for a long time. This method provides a facile strategy for the preparation of ultrastable composites employing both perovskites and light-emitting polymers and deepens our understanding of the exciton dynamics in such composite materials. It is beneficial for the development of next-generation light-emitting devices and displays. [ABSTRACT FROM AUTHOR]

The advent of the "information age" ushered in renewed expectations of systematic urban spatial structure transformation. However, few studies have quantitatively assessed these changes, especially the decentralisation of manufacturing employment. This paper tests hypotheses regarding the decentralisation–centralisation effect of information and communication technology (ICT) on manufacturing. Further, the work employs an IV‐GMM estimation technique to estimate the models, to alleviate potential bias brought by endogeneity. The results suggest that the adoption of ICT is highly related to the decentralisation of manufacturing employment on the city‐proper scale in China. The conclusion drawn is that ICT has shaped the manufacturing decentralisation of cities in China. [ABSTRACT FROM AUTHOR]

Although the literature often suggests that the economic prowess of 'polycentric urban regions' partly results from the ability of their constituent cities to promote functional spillovers through 'borrowed size', the empirical evidence remains scarce. This paper finds that polycentricity boosts the positive functional spillovers of producer service sector of city clusters beyond their boundaries only when city clusters have larger population and better urban infrastructure connectivity. And consequently, functional spillovers increase urban labour productivity. The labour division among cities could be the essential mechanism for the linkage between polycentricity and regional functional spillovers. [ABSTRACT FROM AUTHOR]

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ABSTRACT Using data from 161 Chinese cities, this paper investigates the effects of various dimensions of urban spatial structure on the ownership and commute mode split of automobile. Results confirm the positive effects of city size on auto ownership and mode split and the negative effect of density on auto ownership. Echoing a small number of studies, this research discovers the seemingly counterintuitive effect of jobs-housing balance on the use of automobiles, probably due to the potential advantage of public transit relative to driving in dense and congested Chinese cities. Cities should emphasize public transit and maintain density in the future. [ABSTRACT FROM AUTHOR]

Urban traffic is embedded in and fundamentally shaped by the spatial pattern of urban land use, such as city size, density, extent of polycentricity, and the relationship between employment and residential locations. Previous evidence, mainly from European and American cities, suggests that the duration of commute trips increases with city size and the spatial separation between jobs and housing. On the other hand, the influences of density and polycentricity are less clear. Using data from 164 cities in China, this study empirically analyzes the relationship between city average commute duration and multiple dimensions of urban spatial structure. Controlling for economic, demographic, and infrastructure characteristics, we find that commute duration correlates positively with city size and jobs–housing separation but negatively with density and polycentricity. As one of the earliest studies on commute cost in the rapidly urbanizing and motorizing Chinese cities, this study can help Chinese decision makers improve urban economic and environmental efficiency through spatial planning and policy making. Specifically, compact, mixed-use, and polycentric spatial development may ease the burden of commute, and thus substitute for unnecessary infrastructure investment and energy consumption during a period of rapid urban expansion in China. [ABSTRACT FROM AUTHOR]

A single-channel algorithm was proposed in order to study effect of intermittent hypoxic training on hypoxia tolerance based on EEG pattern. EEG was decomposed by ensemble empirical mode decomposition into a finite number of intrinsic mode functions (IMFs) based on the intrinsic local characteristic time scale. Analytic amplitude, analytic frequency, and recurrence property quantified by recurrence quantification analysis were explored on IMFs, and the first two scales revealed difference between normal EEG and hypoxia EEG. Classification accuracy of hypoxia EEG and normal EEG could reach 67.8% before decline of neurobehavioral ability, which represented that hypoxia EEG pattern could be detected at an early stage. Classification accuracy of hypoxia EEG and normal EEG increased with time and deepened intensity of hypoxia was observed by regular shift of hypoxia EEG pattern with time in a three dimensional subspace. The reduced shift and classification accuracy after intermittent hypoxic training represented that hypoxia tolerance enhanced. [ABSTRACT FROM AUTHOR]