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Thermochromic photonic crystal (PC) is a promising material for anti-counterfeiting applications, but there are still challenges to further improve the anti-counterfeiting performance and the practicability in usage. Here, a disposable thermally triggered PC anti-counterfeiting tag with irreversible response and multi-step color changes is developed based on the thermochromic Silica/(Polyethylene glycol-Ethoxylated trimethylolpropane triacrylate) (SiO2/(PEG-ETPTA)) double-layer film. The fast and irreversible thermal response come from the quick melting and infiltration of PEG-ETPTA into the PCs upon heating. The multi-step color change at different temperatures originated from the regioselective control of the UV curing degree of the PEG-ETPTA layer and the resulting thermochromic temperature of the double-layer film. Therefore, the invisible PC pattern on the tag can be revealed part by part upon heating and became invisible again after overheating, which offered diversified visual effects and enhanced anti-counterfeiting performances.
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The environmental tax system is effective in pollution abatement. However, levying an environmental tax may be detrimental to economic growth. Reasonable use of environmental tax revenue may achieve both environmental protection and economic growth. This study proposes to earmark environmental tax revenue for pollution treatment. Taking fiscal expenditure theory into consideration, environmental tax revenue usage is divided into transfer expenditure and purchase expenditure. An environmental computable general equilibrium (CGE) model is established to evaluate the effects of environmental tax revenue usage. The optimal choice is to increase the environmental tax rate and simultaneously use tax revenue for cleaner production subsidies and end-of-pipe treatment expenditures. Under the optimal scenario, pollutant retention decreases by 21.45%, and GDP increases by 0.006%. For most regions in China, it is better to raise the environmental tax rate to the middle level of a specified range. Moreover, the government should distribute environmental tax revenue evenly across the expenditure of different environmental protection projects.
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Poluentes Ambientais , Motivação , Poluição Ambiental , Impostos , Desenvolvimento EconômicoRESUMO
Traditional thermochromic photonic crystal (PC) usually has a slow and reversible thermal response, which limits its application in thermal printing. Here, the authors develop a thermochromic "SiO2 -PC/PEG" double layer structure with a responding time of milliseconds for fast thermal printing. Controlled by the print-head, the polyethylene glycol (PEG) melts, infiltrates, and solidifies within the interparticle voids, which instantly and irreversibly changes the refractive index and produces the PC pattern. Multicolor printing can be realized by tuning the size and type of colloidal particles. Resolution as high as 300 DPI is achieved to print the high-resolution patterns and then the grayscale patterns based on the control of pixel densities. Different from fiber thermal paper, the "SiO2 -PC/PEG" film has no toxic bisphenol A and possesses superior light stability for keeping the images longer. It is fully compatible with the commercial printer, which provides a mature solution for fast and convenient preparation of PC patterns.
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Polietilenoglicóis , Dióxido de Silício , Óptica e Fotônica , Fótons , Impressão TridimensionalRESUMO
Electrocatalytic reduction of carbon dioxide to valuable chemicals is a sustainable technology that can achieve a carbon-neutral energy cycle in the environment. Electrochemical CO2 reduction reaction (CO2 RR) processes using metal-organic frameworks (MOFs), featuring atomically dispersed active sites, large surface area, high porosity, controllable morphology, and remarkable tunability, have attracted considerable research attention. Well-defined MOFs can be constructed to improve conductivity, introduce active centers, and form carbon-based single-atom catalysts (SACs) with enhanced active sites that are accessible for the development of CO2 conversion. In this review, the progress on pristine MOFs, MOF hybrids, and MOF-derived carbon-based SACs is summarized for the electrocatalytic reduction of CO2 . Finally, the limitations and potential improvement directions with respect to the advancement of MOF-related materials for the field of research are discussed. These summaries are expected to provide inspiration on reasonable design to develop stable and high-efficiency MOFs-based electrocatalysts for CO2 RR.
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A highly active and stable Ni-based catalyst is the focal point for research on dry reforming of methane (DRM). Here, NixGay/La2O3-LDO catalysts composed of highly dispersed NixGay and La2O3 nanoparticles supported by the MgO/Al2O3 layered double oxide (LDO) nanosheets were synthesized by chemical methods. According to transmission electron microscopy (TEM), energy-dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), CO2-TPD, diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), and thermal gravitational analysis (TGA), a synergistic reaction mechanism was proposed to explain the superior performance of the Ni0.8Ga0.2/La2O3-LDO catalyst. The NixGay alloy catalyst provides an effective way to balance the speed of CH4 cracking and CO2 disassociation, and the La2O3 promoter enriched the CO2 and ensured the generation of active O in time. They worked together to inhibit carbon accumulation and significantly improve the catalyst's activity and stability.
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OBJECTIVE: (Background): Alzheimer's disease (AD), clinically characterized by the progressive neurodegenerative condition and cognitive impairment, is one of the main causes of disability in elder people worldwide. Recently, several animal studies indicated that the 'gut-brain' axis might contribute to the amyloid deposition of AD. However, data about gut dysbiosis in human AD remains scarce in the literature, especially including the whole process of AD. In this prospective and cross-sectional study, we aimed at identifying differences in microbiome between patients with AD (Pre-onset stage amnestic mild cognitive impairment, aMCI; and AD) and the normal cognition healthy controls (HC). Additionally, the potential association between IM and clinical characteristics of AD was evaluated. METHODS: A total of 97 subjects (33 AD, 32 aMCI, and 32 HC) were recruited in the study. The composition of gut bacterial communities was determined by 16S ribosomal RNA Miseq sequencing. In addition, Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) was used to predict function shift of intestinal microbiota. The Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA) or Clinical Dementia Rating (CDR) scores were used to evaluate the severity of cognitive impairment in patients. RESULTS: The fecal microbial diversity was decreased in AD patients compared with aMCI patients and HC. And the microbial composition was distinct among aMCI, AD and healthy control groups. Among bacterial taxa, the proportion of phylum Firmicutes was significantly reduced (Pâ¯=â¯0.008), whereas Proteobacteria (Pâ¯=â¯0.024) was highly enriched in the AD compared with HC. In addition, similar alterations were observed at the order, class and family levels of these two phyla. And Gammaproteobacteria, Enterobacteriales and Enterobacteriaceae showed a progressive enriched prevalence from HC to aMCI and AD patients. Further, a significant correlation was observed between the clinical severity scores of AD patients and the abundance of altered microbiomes. Moreover, the KEGG results showed the increased modules related to glycan biosynthesis and metabolism in AD and aMCI patients and decreased pathways related to immune system in AD patients. Importantly, the discriminating models based on predominant microbiota could effectively distinguish aMCI and AD from HC (AUCâ¯=â¯0.890, 0.940, respectively), and also AD from aMCI (AUCâ¯=â¯0.925). Notably, the models based on the abundance of family Enterobacteriaceae could distinguish AD from both aMCI (AUCâ¯=â¯0.688) and HC (AUCâ¯=â¯0.698). CONCLUSIONS: Distinct microbial communities, especially enriched Enterobacteriaceae, were associated with patients with AD when compared with predementia stage aMCI and healthy subjects. These novel findings will give new clues to understand the disease and provide new therapeutic target for intervention or a marker for this disease.
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Doença de Alzheimer/diagnóstico , Disfunção Cognitiva/diagnóstico , Microbioma Gastrointestinal/genética , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/genética , Doença de Alzheimer/microbiologia , Amnésia/diagnóstico , Amnésia/microbiologia , Área Sob a Curva , Povo Asiático , Biomarcadores , Encéfalo/fisiopatologia , China , Cognição , Disfunção Cognitiva/genética , Disfunção Cognitiva/microbiologia , Estudos de Coortes , Estudos Transversais , Fezes/microbiologia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Estudos Prospectivos , RNA Ribossômico 16S/genéticaRESUMO
Monodisperse ZnO particles with adjustable size have been produced on a large scale by two-step seeding-growth polyol reactions. Through spin coating of supersaturated ZnO/diethylene glycol solution and evaporation of solvent, opaline ZnO photonic crystal (PC) film with good crystallinity and uniform photonic structures can be prepared from these ZnO particles. Compared with a disorderly stacked ZnO film, the ZnO PC film shows a higher activity in photocatalytic reduction of CO2 due to the generated slow photons at the edge of the photonic band gap and their promotion to the light absorption. When the electronic band gap of ZnO matches the red edge of the photonic band gap of ZnO PC, the enhancement factor of photocatalytic activity represented by CO evolution can be maximized to 2.64-fold in the current experiment. Compared to the traditional inverse opal photocatalysts, the opaline ZnO photocatalysts are prepared by simplified and scalable procedures, and they still possess the same enhancement in activity compared to ZnO without the photonic structure, which might be broadly used in solar energy utilization, environment protection, and many other green chemical processes in the future.
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A Zr-based metal-organic framework (MOF) catalyst, Pt/Au@Pd@UIO-66, is assembled, where UIO-66 is Zr6 O4 (OH)4 (BDC)6 (BDC = 1,4-benzenedicarboxylate). The gold nanoparticles (NPs) act as the core for the epitaxial growth of Pd shells, and the core-shell monodispersed nanosphere Au@Pd is encapsulated into UIO-66 to control its morphology and impart nanoparticle functionality. The microporous nature of UIO-66 assists the adsorption of Pt NPs, which in turn enhances the interaction between NPs and UIO-66, favoring the formation of isolated and well-dispersed Pt NP active sites. This MOF exhibits high catalytic activity and CO product selectivity for the reverse-water-gas-shift reaction in a fixed-bed flow reactor.
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Nonanalogous climates (NACs), climates without modern analogs on Earth, challenge our understanding of eco-evolutionary processes that shape global biodiversity, particularly because of their propensity to promote novel ecosystems. However, NAC studies are generally inadequate and partial. Specifically, systematic comparisons between the future and the past are generally lacking, and hydraulic NACs tend to be underemphasized. In the present study, by adopting a frequency distribution-based method that facilitates the procedures of contributions parsing and conducting multiple comparisons, we provide a global overview of multidimensional NACs for both the past and the future within a unified framework. We show that NACs are globally prevalent, covering roughly half of the land area across the time-periods under investigation, and have a high degree of spatial structure. Patterns of NACs differ dramatically between the past and the future. Hydraulic NACs are more complex both in spatial patterns and in major contributions of variables than are thermal NACs. However, hydraulic NACs are more predictable than originally thought. Generally, hydraulic NACs in the future (2100 AD) exhibit comparable predictability to thermal NACs in the last glacial maximum (LGM) (21k BP). Identifying these NAC patterns has potential implications on climate-adaptive managements and preparing in advance to possibly frequent novel ecosystems. However, a learning-from-the-past strategy might be of limited utility for management under present circumstances.
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Mudança Climática , Ecossistema , Biodiversidade , Evolução Biológica , Clima , Previsões , Modelos TeóricosRESUMO
The uncalcined but highly dispersive oxide-supported metal catalyst for liquid phase reactions may suffer from the agglomeration of metal nanoparticles and the drop of metal catalyst in solution, which will decrease the activity and shorten their life in catalysis. Here, a one-pot successive polyol reaction was developed to prepare M-E xO y colloidal particles as heterogeneous nanocatalysts, which merge the controlled synthesis of metal catalysts and oxide supports, the in situ loading of catalyst, and even the mesopore amplification into a highly integrated process. Unlike the traditional surface-deposited catalysts, the noble metal nanoparticles even with a large amount of loading are internally dispersed in the mesoporous oxide particles, which show higher activity and stability in the hydrogenation of nitroaromatics compared to the isolated nanocatalysts or surface-deposited catalysts. The improved activity and stability comes from the physical confinement of metal nanoparticles and good mass transportation of substrate/product within the support particles. This work proposed a novel method to prepare highly dispersed metal catalysts, which could be potentially useful to heterogeneous catalytic reactions with high-throughput and long-life demands.
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Nitrogen adsorption-desorption for mesopore characterization requires the using of expensive instrumentation, time-consuming processes, and the consumption of liquid nitrogen. Herein, a new method is developed to measure the pore parameters through mixing a mesoporous substance with a supersaturated SiO2 colloidal solution at different temperatures, and subsequent rapid measurement of reflection changes of the precipitated liquid photonic crystals. The pore volumes and diameters of mesoporous silica were measured according to the positive correlation between unit mass reflection change (Δλ/m) and pore volume (V), and the negative correlation between average absorption temperature (T) and pore diameter (D). This new approach may provide an alternative method for fast, convenient and economical characterization of mesoporous materials.
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A test-paper-like photonic crystal (PC) viscometer is fabricated based on the positive correlation between viscosity and the infiltration time for viscous liquid to entirely soak the PC film. It can be broadly used in different occasions to quickly determine the viscosity for many liquids, considering its portable and disposable characteristics and the requirement of little samples.
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BACKGROUND AND AIMS: It is controversial whether patients with cirrhosis benefit from the intensive care unit (ICU) management. To identify the patients in whom ICU care may offer recovery, this study aimed to determine specific risk factors and to establish a novel prognostic score for 3-month mortality in critically ill patients with cirrhosis. METHODS: An observational study was performed from August 2008 to May 2014, encompassing 349 critically ill patients with cirrhosis during their ICU stay (a 70% training and 30% validation set). RESULTS: The overall 3-month mortality rate was 68.1% in training cohort. Prothrombin time, serum bilirubin, use of vasopressors, hepatic encephalopathy, and systemic inflammatory response syndrome at admission were identified as being strongly correlated with the 3-month prognosis. Based on these five variables, a modified score for critically ill cirrhosis (MSCIC) was developed. An increasing MSCIC was significantly correlated with a reduction in the rate of survival (P < 0.001). Moreover, excellent predictive power was found when the MSCIC was used (area under the receiver operating characteristic curve: 0.856 ± 0.047), which was significantly better than the prognostic efficiency of Acute Physiology and Chronic Health Evaluation II (P < 0.001), Model for End-stage Liver Disease (P = 0.02), Simplified Acute Physiology Score (P = 0.023), and the Child-Turcotte-Pugh score (P = 0.01); the MSCIC score was slightly better than that of Chronic Liver Failure-Sequential Organ Failure Assessment (P = 0.068). The similar result was obtained in validation set. CONCLUSIONS: The MSCIC is an easily adopted tool with a high prognostic efficacy for patients with advanced cirrhosis; MSCIC may act as a supplement to the clinical judgment of physicians when considering the prognosis.
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Estado Terminal/mortalidade , Cirrose Hepática/mortalidade , Adulto , Idoso , Estudos de Coortes , Cuidados Críticos , Feminino , Seguimentos , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Curva ROC , Fatores de Risco , Taxa de Sobrevida , Fatores de TempoRESUMO
Fe3O4/ZIF-8 nanoparticles were synthesized through a room-temperature reaction between 2-methylimidazolate and zinc nitrate in the presence of Fe3O4 nanocrystals. The particle size, surface charge, and magnetic loading can be conveniently controlled by the dosage of Zn(NO3)2 and Fe3O4 nanocrystals. The as-prepared particles show both good thermal stability (stable to 550 °C) and large surface area (1174â m(2) g(-1)). The nanoparticles also have a superparamagnetic response, so that they can strongly respond to an external field during magnetic separation and disperse back into the solution after withdrawal of the magnetic field. For the Knoevenagel reaction, which is catalyzed by alkaline active sites on external surface of catalyst, small Fe3O4/ZIF-8 nanoparticles show a higher catalytic activity. At the same time, the nanocatalysts can be continuously used in multiple catalytic reactions through magnetic separation, activation, and redispersion with little loss of activity.
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Óxido Ferroso-Férrico/química , Imidazóis/química , Nanocompostos/química , Nanopartículas/química , Nitratos/química , Compostos de Zinco/química , Catálise , Fenômenos Magnéticos , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Propriedades de SuperfícieRESUMO
Thermochromic photonic crystals are promising materials for thermal printing due to their unfaded colors under chemical/illuminated environments and the absence of toxic chemicals. However, the slow thermochromic response, the multistep printing procedures, the use of inks or developing liquids, and the requirement of expensive parts in printers limit their applications. Here, a thermochromic polyurethane/hydrophobic-SiO2 photonic crystal/paraffin (PU/HPO-SiO2 -PC/Para) film with an integrated multilayer structure is fabricated for all-solid-state and single-step thermal printing that is fully compatible with commercial printers. The fast thermochromic response in milliseconds enables high-resolution and grayscale printing as the paraffin infiltration and the color change can be finely controlled in a microscale range. The integrated and hydrophobic multilayer structure renders the thermochromic film good stability in daily liquids, which addresses the long-existing concern of print fading. Meanwhile, the integrated multilayer structure also enhances the mechanical stability when it is deposited on fibrous paper so that people can fold, cut, or staple the thermal papers, and make notes confidently in practical usage.
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Anticounterfeiting materials based on the photonic crystal (PC) have attracted great interest due to their unique visual effects originating from the changeable structural colors under various external stimuli. However, there still are challenges to improving the anticounterfeiting performance by enhancing the complexity and diversity of the color changes. Here, we fabricated an electrically triggered anticounterfeiting tag by encapsulating the responsive PC with the surface-modified and patterned ITO electrode. The degree of Au deposition or chemical etching in different regions of the ITO was precisely controlled to achieve multi-level differentiated electrical responses, which made the invisible pattern of the tag at 0 V be "revealed in multicolor form" or "gradually revealed" under increasing voltages. The tag possessed two working modes, more diversified visual effects, good usability, and reversibility, which let it become a potentially useful material for anti-counterfeiting applications in the future.
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Selective hydrogenation of nitroaromatics is a crucial industrial reaction, but there are still challenges in developing nanocatalysts with stable active centers, yet easily recyclable characteristics. Here, a magnetically separable Pd/Fe3O4@SiO2 nanocatalyst was prepared through the seeding growth of silica on the Fe3O4 nanocrystal cluster (NC) followed by in situ reduction of Pd nanoparticles (NPs) on the amino group modified Fe3O4@SiO2 nannotube (NT). The nanocatalyst showed good activity and stability in the hydrogenation of a series of nitroaromatics as the Pd NPs were highly dispersed on the nanotubes. Meanwhile, it could be easily separated from the reaction solution and well-redispersed in the solvent for the next-round reaction due to the superparamagnetic property of the Fe3O4 NC and the good dispersibility of silica in many organic solvents. The magnetically separable nanocatalyst combined the high activity of the nanocatalyst and the convenient separation of a traditional heterogeneous catalyst, which effectively promote the practical application of nanomaterials in catalysis.
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While electric vehicles (EVs) are developing at a high speed in China, the power battery market is facing a decommissioning peak. The problem is that the recycling situation of domestic power batteries is not ideal, partly due to neglect by consumers. By considering the recycling system, mode, and policy of China's EV power batteries, we construct a tripartite evolutionary game model of the government, consumers and EV manufacturers; analyse the stable strategy adjustment mechanisms of tripartite participation in this recycling cooperation game; and simulate the tripartite evolutionary game. The results show that when the initial willingness of the government, consumers and EV manufacturers to recycle power batteries is not strong, the government takes the lead, driving EV manufacturers and consumers to participate in power battery recycling. When the government, consumers and EV manufacturers have medium or high levels of initial willingness, the government evolves and chooses a nonregulation strategy. In addition, by simulating the impact of changes in consumer-related influencing factors on this tripartite evolutionary game, we find that subsidies for recycling power batteries are a key factor affecting consumers' strategy choices and that boosting recycling compensation for consumers can improve their enthusiasm to participate in such recycling. Therefore, to improve the recycling of power batteries for EVs, in terms of both efficiency and percentage of deployment, the Chinese government should strengthen public education on power battery recycling, further integrate informal recycling channels, and balance the distribution of profits among consumers for recycling compensation.
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Fontes de Energia Elétrica , Reciclagem , Reciclagem/métodos , China , Teoria dos Jogos , Comportamento Cooperativo , GovernoRESUMO
The gut microbiota plays an important role in the immunology, physiology and growth and development of animals. However, currently, there is a lack of available sequencing data on the gut microbiota of Asian badgers. Studying the gut microbiota of Asian badgers could provide fundamental data for enhancing productivity and immunity of badgers' breeding, as well as for the protection of wild animals. In this study, we first characterized the composition and structure of the gut microbiota in the large intestines of wild and captive Asian badgers during summer and winter by sequencing the V3-V4 region of the 16S ribosomal RNA gene. A total of 9 dominant phyla and 12 genera among the bacterial communities of the large intestines exhibited significant differences. Our results showed that Firmicutes and Proteobacteria were the most predominant in both wild and captive badgers, regardless of the season. Romboutsia, Streptococcus and Enterococcus may represent potential sources of zoonoses, warranting further attention and study. Our findings indicated that the diversity and availability of food resources were the most important influencing factors on the gut microbiota of Asian badgers, providing fundamental data for the protection and conservation of wild animals. Variation in the gut microbiota due to season, age and sex in both wild and captive Asian badgers should be considered in future research directions. Furthermore, combined multi-omics studies could provide more information for wild animal conservation, and enhancing our understanding of the molecular mechanism between the microbiota and host.
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Animais Selvagens , Microbioma Gastrointestinal , Mustelidae , RNA Ribossômico 16S , Estações do Ano , Animais , Mustelidae/microbiologia , RNA Ribossômico 16S/genética , Animais Selvagens/microbiologia , Masculino , Feminino , Bactérias/classificação , Bactérias/genéticaRESUMO
Mineral licks are indispensable habitats to the life history of large mammal herbivores (LMH). Geophagy at licks may provide the necessary minerals for LMH, while LMH may be ecosystem engineers of licks by altering vegetation cover and soil physicochemical properties (SPCP). However, the precise relationship between the LMH and licks remains unclear. To clarify the geophagy function of licks for LMH and their influence on soil at licks, we recorded visitation patterns of sika deer around licks and compared SPCP and microbial communities with the surrounding matrix in a firebreak adjacent to the Sino-Russian border. Our study indirectly supports the "sodium supplementation" hypothesis. Proofs included (1) a significantly higher sodium, iron, and aluminum contents than the matrix, while lower carbon, nitrogen, and moisture contents; (2) significantly higher deer visitation during sodium-demand season (growing season), along with an avoidance of licks with high iron contents, which is toxic when overdose. The microbes at the licks differed from those at the matrix, mainly driven by low soil carbon and nitrogen and altered biogeochemical cycles. The microbial communities of licks are vulnerable because of their unstable state and susceptibility to SPCP changes. Structural equation modeling (SEM) clearly showed a much stronger indirect effect of deer on microbes at licks than at the matrix, especially for bacteria. Multiple deer behaviors at licks, such as grazing, trampling, and excretion, can indirectly shape and stabilize microbes by altering carbon and nitrogen input. Our study is the first to characterize soil microbial communities at mineral licks and demonstrate the processes by which LMH shapes those communities. More studies are required to establish a general relationship between the LMH and licks to promote the conservation of natural licks for wildlife.