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Against the backdrop of an aging population, China is actively experimenting with an innovative elderly care model, so smart community elderly care has recently received widespread attention. However, the results of the implementation of the model have not yet met the expectation due to the variety of interests among the relevant participants. In this study, we identified the most core stakeholders in smart community elderly care, developed a four-party evolutionary game model including local governments, communities, service supply enterprises and households with elderly members. By applying the system dynamics method, we simulate the evolutionary paths and explore the complex interactions at the multiparticipant level in order to facilitate the transition of community elderly care services from traditional to smart, and then propose managerial insights for accelerating the construction of smart community elderly care. The results suggest that: (1) the four players in the game influence each other and are intimately related, and the benign interaction between them will further stimulate the vitality of the smart community elderly care industry; (2) appropriate improvement in policy support will strongly promote smart community elderly care, and the incentive effect on the demand side (households with elderly members) is more significant; (3) when households' preference for smart services increases, and the perceived value to communities and enterprises reaches a certain threshold, communities and enterprises will actively adopt smart solution and technology as well as develop stable portfolio strategy; (4) measures such as simultaneously increasing the level of smart and resource synergy will promote the system evolution toward smart services, and the system is more sensitive to the internal behavior of the enterprise than the external behavior between community and enterprise.
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Serviços de Saúde para Idosos , China , Humanos , Idoso , Teoria dos Jogos , MotivaçãoRESUMO
Magnetoelectric coupling represents a significant breakthrough for next-generation electronics, offering the ability to achieve nonvolatile magnetic control via electrical means. In this comprehensive investigation, leveraging first-principles calculations, we unveil a robust magnetoelectric coupling within multiferroic heterostructures (HSs) by ingeniously integrating a non-van der Waals (non-vdW) magnetic FeTiO3 monolayer with the ferroelectric (FE) Ga2O3. Diverging from conventional van der Waals (vdW) multiferroic HSs, the magnetic states of the FeTiO3 monolayer can be efficiently toggled between ferromagnetic (FM) and antiferromagnetic (AFM) configurations by reversing the polarization of the Ga2O3 monolayer. This intriguing phenomenon arises from polarization-dependent substantial interlayer electron transfers and the interplay between superexchange and direct-exchange magnetic couplings of the iron atoms. The carrier-mediated interfacial interactions induce crucial shifts in Fermi level positions, decisively imparting distinct electronic characteristics near the Fermi level of composite systems. These novel findings offer exciting prospects for the future of magnetoelectric technology.
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Two-dimensional (2D) magnetic materials with large and tunable magnetocrystalline anisotropy (MCA) provide unique opportunities to develop various spintronic devices. We, herein, propose an experimentally feasible 2D material platform, Mn2X2 (X = As, Sb), which is a family of intrinsic ferromagnet. Using first-principles calculations, we show that 2D Mn2X2 (X = As, Sb) with a robust ferromagnetic ground state exhibits not only a large perpendicular magnetic anisotropy (PMA), but also significant strain-driven modulation behaviors under external biaxial strain. The analysis of the results demonstrates that the dominant contribution to the change of MCA of Mn2As2 and Mn2Sb2 primarily arises from the Mn and Sb atoms, respectively. Moreover, we reveal that the underlying origin is the competitive mechanism for the spin-orbit coupling (SOC) between different orbitals and spin channels. These findings indicate that 2D Mn2X2 (X = As, Sb) provides a promising material platform for the next generation of ultra-low energy memory devices.
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In order to develop carbonyl iron-enhanced electromagnetic wave-absorbing composites, this paper utilizes two different morphologies of carbonyl iron powder (CIP), spherical and flake-like, which are blended with aqueous polyurethane (PU) in three different ratios to prepare impregnating solutions. Polyester (PET) needle-punched nonwoven materials are impregnated with these solutions to produce electromagnetic wave-absorbing composites. First, electromagnetic parameters of the two CIP particle types, spherical carbonyl iron (SCIP) and flake-like carbonyl iron (FCIP), are tested with the coaxial method, followed by calculation of the results of their electromagnetic wave absorption performance. Next, the composites are subjected to microscopic morphology observation, tensile testing, and arched frame method electromagnetic wave absorption performance testing. The results indicate that the microwave absorption performance of FCIP is significantly better than that of SCIP. The minimum reflection loss value for F3, a kind of FCIP-modified nonwoven fabric, at the thickness of 1 mm, at 18 GHz is -17 dB. This value is even better than the calculated RL value of CIP at the thickness of 1 mm. The anisotropic shape of flake-like magnetic materials is further strengthened when adhering to the surface of PET fiber material. Additionally, the modified composites with carbonyl iron exhibit higher tensile strength compared with pure PET. The addition of fibrous skeletal materials is expected to enhance the impedance matching of flake-like magnetic particles, forming a wearable and microwave-absorbing composite.
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Two-dimensional (2D) ferromagnetic materials with tunable magnetocrystalline anisotropy (MCA) provide unique opportunities for developing the next-generation data-storage and information devices. Herein we systematically investigate the electronic and magnetic properties of the 1T-MX2 (M = Cr, Mn, Fe, Co; X = As, Sb) monolayers, and identify the stable 2D ferromagnets as well as their MCA energies. Notably, the results demonstrate that the biaxial strain and carrier doping effects have a significant influence on their magnetic behaviors. In addition to the robust FM states, three FM monolayers yield tunable MCA depending on the applied strain type and carrier doping values. The dominant contributions to these complicated modifications in MCA are mainly attributed to the strain or carrier doping induced alterations of specific M-derived 3d states, which in turn lead to the changes of their spin-orbit coupling (SOC) energies. These findings show effective approaches to control 2D magnetism and suggest that these 2D FM materials may be promising candidates to design highly efficient memory devices.
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This study aims to investigate the influences of carbon nanotubes (CNTs) and graphene flakes (GFs) on the microwave absorption performance of nonwovens. Nonwovens were modified with CNTs and GFs through an impregnation method, creating a series of absorption samples with different carbon nanomaterial contents. Then the absorption performance of the samples was tested on both sides in the X-band (8.2~12.4 GHz) and the Ku-band (12~18 GHz) using the arch method. The experimental results showed that the absorption performance of GF-impregnated nonwovens was superior to that of CNT-impregnated nonwovens, and the overall absorption performance in the Ku-band was better than in the X-band. At a CNT content of 5 wt.%, the reflection loss of the impregnated nonwovens on the backside reached a minimum of -14.06 dB and remained below -10 dB in the 17.42~17.88 GHz frequency range. The sample fabricated with 4 wt.% GFs in the impregnation solution exhibited the best absorption performance, with minimum reflection losses of -15.33 dB and -33.18 GHz in the X-band and Ku-band, respectively. When the GFs were at 3 wt.%, the absorption bandwidth below -10 dB reached 4.16 GHz. In contrast to CNT-impregnated nonwovens, the frontside of GF-impregnated nonwovens demonstrated better absorption performance in the Ku-band. The results of this work provide experimental data support for the fabrication and application of microwave absorption materials.
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Ceramic-based nanofiber materials have attracted attention due to their high-temperature resistance, oxidation resistance, chemical stability, and excellent mechanical performance, such as flexibility, tensile, and compression, which endow them with promising application prospects for filtration, water treatment, sound insulation, thermal insulation, etc. According to the above advantages, we, therefore, reviewed the ceramic-based nanofiber materials from the perspectives of components, microstructure, and applications to provide a systematical introduction to ceramic-based nanofiber materials as so-called blankets or aerogels, as well as their applications for thermal insulation, catalysis, and water treatment. We hope that this review will provide some necessary suggestions for further research on ceramic-based nanomaterials.
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Background: The growing problem of adolescent mobile phone addiction has attracted significant attention, underscoring the importance of identifying approaches to address it. Exercise has been found to reduce adolescent mobile phone addiction; however, its mechanism remains unclear. This review aims to elucidate the potential moderating factors between exercise and mobile phone addiction based on previous studies to provide a reference for adolescents to effectively participate in exercise to reduce mobile phone addiction. Methods: Articles were searched in the CNKI, Web of Science, Scopus, Cochrane, PsycINFO, and PubMed databases according to the inclusion criteria and followed the Preferred Reporting Items for Systematic Assessment and Meta-analysis (PRISMA). The quality of the literature was assessed by two independent reviewers using the Cochrane Collaboration Risk of Bias tool for methodological quality assessment. Meta-analysis was performed using Stata 15.1 software for Meta-analysis, standardized mean difference (SMD) was combined using a random effects model, and subgroup analysis was used to explore heterogeneity. Results: A total of 12 studies, 17 samples, and 861 subjects were included in the meta-analysis, and all studies were randomized controlled trials. The findings revealed that the exercise intervention significantly reduced mobile phone addiction in adolescents (SMD = -3.11; 95% CI: -3.91, -2.30; p < 0.001). The intervention effect was moderated by multiple variables, such as the measurement tools, exercise intervention types, cycles, frequency, and duration of a single exercise intervention. Conclusion: Our findings suggest that exercise could serve as an effective strategy for preventing or ameliorating mobile phone addiction in adolescents. Based on the results of this study, we encourage mobile phone-addicted adolescents to engage in a single exercise using a mix of skills for 30-60 min three or more times weekly for more than eight consecutive weeks.
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Introduction: Perioperative hemoglobin (Hb) levels can influence tissue metabolism. For clinical physicians, precise Hb concentration greatly contributes to intraoperative blood transfusion. The reduction in Hb during an operation weakens blood's oxygen-carrying capacity and poses threats to multiple systems and organs of the whole body. Patients can die from perioperative anemia. Thus, a timely and accurate non-invasive prediction for patients' Hb content is of enormous significance. Method: In this study, targeted toward the palpebral conjunctiva images in perioperative patients, a non-invasive model for predicting Hb levels is constructed by means of deep neural semantic segmentation and a convolutional network based on a priori causal knowledge, then an automatic framework was proposed to predict the precise concentration value of Hb. Specifically, according to a priori causal knowledge, the palpebral region was positioned first, and patients' Hb concentration was subjected to regression prediction using a neural network. The model proposed in this study was experimented on using actual medical datasets. Results: The R 2 of the model proposed can reach 0.512, the explained variance score can reach 0.535, and the mean absolute error is 1.521. Discussion: In this study, we proposed to predict the accurate hemoglobin concentration and finally constructed a model using the deep learning method to predict eyelid Hb of perioperative patients based on the a priori casual knowledge.
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Anemia , Hemoglobinas , Humanos , Hemoglobinas/metabolismo , Túnica Conjuntiva , Redes Neurais de ComputaçãoRESUMO
The demand for ultra-compact spintronic devices with lower energy consumption and higher storage density requires two-dimensional (2D) magnetic materials with tunable magnetocrystalline anisotropy (MCA) energy. Employing first-principles calculations, we have investigated the influence of W atom adsorption and biaxial strain on the magnetic properties of layered Fe3GeTe2. We demonstrate that the adsorption mode and applied strain play a critical role in determining their MCA. The Fe3GeTe2 adsorbed with W atoms undergoes a change in spin reorientation from out-of-plane to in-plane magnetization, yielding a colossal MCA up to -13.112 erg cm-2. The dominant contribution to these unexpected changes mainly arises from the W atoms with emerged magnetism and large SOC. Moreover, our results reveal distinct strain-driven modulation behaviors of the MCA in different adsorption configurations. The underlying atomistic mechanism mainly involves the alteration of various W-derived 5d-orbital states under the strain effect, leading to competitive changes of the corresponding spin-orbit coupling energies between the spin-parallel and spin-flip channels. Our findings not only provide useful guidance in optimizing the MCA performance of 2D magnetic crystals but also highlight the potential of W-adsorbed Fe3GeTe2 in the applications of new-generation magnetic memory storage devices.
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Psychological distress among adolescents adversely affects their development and negatively impacts them later in life. The aim of the present study was to determine whether an association exists between physical exercise and psychological distress and to explore the roles of problematic mobile phone use and learning burnout with respect to this association. A total of 2077 Chinese adolescents were evaluated by using the Physical Exercise Questionnaire, the Self-rating Questionnaire for Adolescent Problematic Mobile Phone Use, the Learning Burnout Questionnaire, and the Depression Anxiety Stress Scale-21. A serial multiple mediation model was constructed using the SPSS PROCESS macro. The results showed that physical exercise was negatively associated with psychological distress in this Chinese adolescent population. Serial multiple mediation analysis revealed that problematic mobile phone use and learning burnout both independently and serially mediated the association between physical exercise and psychological distress. These findings provide evidence suggesting that increased attention should be given to problematic mobile phone use and learning burnout when establishing and implementing specific strategies that leverage greater participation in physical exercise to decrease psychological distress in adolescents.
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Esgotamento Profissional , Uso do Telefone Celular , Telefone Celular , Angústia Psicológica , Adolescente , Exercício Físico , Humanos , Inquéritos e QuestionáriosRESUMO
In this paper, we propose a Robust Breast Cancer Diagnostic System (RBCDS) based on multimode Magnetic Resonance (MR) images. Firstly, we design a four-mode convolutional neural network (FMS-PCNN) model to detect whether an image contains a tumor. The features of the images generated by different imaging modes are extracted and fused to form the basis of classification. This classification model utilizes both spatial pyramid pooling (SPP) and principal components analysis (PCA). SPP enables the network to process images of different sizes and avoids the loss due to image resizing. PCA can remove redundant information in the fused features of multi-sequence images. The best accuracy of this model achieves 94.6%. After that, we use our optimized U-Net (SU-Net) to segment the tumor from the entire image. The SU-Net achieves a mean dice coefficient (DC) value of 0.867. Finally, the performance of the system is analyzed to prove that this system is superior to the existing schemes.
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Neoplasias da Mama , Processamento de Imagem Assistida por Computador , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Redes Neurais de ComputaçãoRESUMO
Spin-orbit torques (SOTs) that arise from materials with large spin-orbit coupling offer a new pathway for energy-efficient and fast magnetic information storage. SOTs in conventional heavy metals and topological insulators are explored extensively, while 5d transition metal oxides, which also host ions with strong spin-orbit coupling, are a relatively new territory in the field of spintronics. An all-oxide, SrTiO3 (STO)//La0.7 Sr0.3 MnO3 (LSMO)/SrIrO3 (SIO) heterostructure with lattice-matched crystal structure is synthesized, exhibiting an epitaxial and atomically sharp interface between the ferromagnetic LSMO and the high spin-orbit-coupled metal SIO. Spin-torque ferromagnetic resonance (ST-FMR) is used to probe the effective magnetization and the SOT efficiency in LSMO/SIO heterostructures grown on STO substrates. Remarkably, epitaxial LSMO/SIO exhibits a large SOT efficiency, ξ|| = 1, while retaining a reasonably low shunting factor and increasing the effective magnetization of LSMO by ≈50%. The findings highlight the significance of epitaxy as a powerful tool to achieve a high SOT efficiency, explore the rich physics at the epitaxial interface, and open up a new pathway for designing next-generation energy-efficient spintronic devices.
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A three-layered electromagnetic (EM) wave-absorbing material was prepared by depositing a Fe3O4 and boron nitride (BN) coating onto the surface of a carbon fiber (CF) by in situ hybridization. The structure, chemical composition, morphology, high-temperature resistance, EM characteristics and EM wave absorption of the composite materials were analyzed. The composite materials contained CFs, and Fe3O4 was distributed along the axial direction of the fiber, whereas BN was found in the outermost coating layer. The proposed preparation method improved the oxidation resistance and EM wave absorption of CF. When the solubility of the metal salt was 20 g/100 ml, the decomposition temperature of the prepared CF/Fe3O4(3)/BN increased by more than 200 °C compared with that of CF/Fe3O4(3). The EM wave loss of less than -5 dB ranged within 8.8-18 GHz, and the effective EM wave-absorbing bandwidth (R < -10 dB) was 4.2 GHz (11.2-15.4 GHz). The prepared CF-based composite material had a lightweight structure, wide absorption band, and strong oxidation resistance. All these findings can serve as a reference for the study of other EM wave-absorbing materials.
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Poor ultraviolet (UV) resistance and good hydrophilicity lead to light aging of aramid fabrics and cause heat damage to the human body. This scenario occurs when the absorbed water by the fabric evaporates and forms high-temperature water vapor in a high-temperature fire environment, which may scald the human body. Herein, a superhydrophobic hollow TNT network structure was built on surfaces of aramid fibers by surface coating fluorinated TiO2 nanotubes (TNTs) to develop an air-permeable, UV-protective, and superhydrophobic coating. The as-prepared superhydrophobic aramid fabric exhibited highly superhydrophobic properties against various solutions of sauce, coffee, methylene blue, active red, Au nanoparticles, Ag nanoparticles, HCl, and NaOH with liquid contact angles up to 152-160°. In addition, the superhydrophobic fabric exhibited excellent UV aging resistance (UV protection factor was 100+; 74.58% of strength retention for 24 h of UV radiation compared with 55.15% of untreated fabric), a self-cleaning function against solid soil, and original wearing characteristics, including good breaking strength and air permeability. The developed superhydrophobic coating technology may promote practical application in high-temperature environments for aramid fabrics due to its good UV resistance, chemical resistance, poromericity, superhydrophobicity, anti-fouling, and self-cleaning properties.
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Carbon fiber is an absorbing material with high strength, acid and alkali resistance, high temperature resistance, flexibility, and processability and plays an important role in the electromagnetic (EM) wave absorption of civil buildings and military equipment. However, its EM wave-absorption performance is poor because of its large complex permittivity and no magnetic loss ability. In this study, dopamine hydrochloride and FeCl3 were used as precursors, and the Fe3O4/N-doped carbon coating was successfully grown in situ on the surface of short carbon fiber (SCF) via dopamine deposition, autopolymerization, FeCl3 solution immersion, and calcination at high temperature to improve its EM wave-absorption property. The obtained Fe3O4/N-doped carbon particles were uniformly attached to the SCF in the form of a thin layer to constitute a unique hierarchical structure. The Fe3O4/N-doped carbon coating/SCF displayed an excellent EM wave-absorption performance. An effective bandwidth of 8.64 GHz and lowest reflection loss of -31.38 dB at 3 mm were achieved because of the significant reduction in complex permittivity and improvement in complex permeability, wave impedance, and EM loss ability of the SCF. The Fe3O4/N-doped carbon coating is expected to show great potential in EM wave-absorption fields.
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The realization of robust intrinsic ferromagnetism in two-dimensional (2D) materials in conjunction with the intriguing quantum anomalous Hall (QAH) effect has provided a fertile ground for novel physics and for the next-generation spintronic and topological devices. On the basis of density functional theory (DFT), we predict that layered 5d transition-metal heavier halides (TMHs), such as ReX3 (X = Br, I), show intrinsic ferromagnetism with high spin polarization and high Curie temperatures. The outstanding dynamic and thermodynamic stability ensures their experimental feasibility. The strong spin-orbit coupling (SOC) of Re makes the electronic structure of the ReI3 monolayer topologically nontrivial with a large Chern number (C = -4). DFT+U calculations reveal that the 2D system undergoes a nontrivial to trivial transition with increasing on-site Hubbard Coulomb interaction U through the emergence of a Dirac cone. This transition is corroborated by the emergence of chiral edge states and the anomalous Hall conductivity. These findings not only demonstrate room-temperature ferromagnetism in atomically thin 5d TMHs, but also pave the way for the potential realization of the QAH effect with high Chern numbers in pristine 2D layers.
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BACKGROUND: Retinoic acid induced 14 (RAI14), also known as NORPEG, is reported as being deregulated in non-small-cell lung cancer, together with having involvement in its cell proliferation as a super enhancer related gene. PURPOSE: The objective of this study was to investigate the role of RAI14 in the progression and metastasis of gastric cancer and explore the associated mechanism. MATERIALS AND METHODS: GEPIA database was used to analyze the expression of RAI14 in gastric cancer. MNK45 and AGS cells were transfected with siRNA-RAI14 to block the expression of RAI14. Cell Counting Kit 8 and colony formation assays were performed to measure cell proliferation. Cell migration and invasion capacities was examined by transwell assay. Apoptosis rate was detected using flow cytometry, and the protein levels of apoptosis-related proteins was determined using Western blot assay. Reverse-transcription PCR assay was used to detect the expressions of RAB31. RESULTS: Gene expression profiling interactive analysis revealed that RAI14 was substantially upregu-lated in gastric cancer and higher expression of RAI14 was associated with worse prognosis. We also observed that the knockdown of RAI14 by siRNA-RAI14 transfection suppressed growth capacity of MKN45 and AGS cells. Also, RAI14 knockdown inhibited migration and invasion of MKN45 and AGS cells in vitro. Moreover, RAI14 knockdown was observed to accelerate cell apoptosis via down-regulation of Bcl-2 and upregulation of Bax in MKN45 and AGS cells. Furthermore, downregulation of RAI14 inhibited the activation of Akt pathway, and activation of Akt by IGF-1 could restore the reduced proliferation induced by RAI14 knockdown. In addition, we found that RAI14 had a positive correlation with the RAB31 in gastric cancer by GEPIA reverse-transcription PCR and Western blot assays, and the reduced proliferation caused by RAI14 knockdown was restored by RAB31. CONCLUSION: RAI14 knockdown inhibited proliferation, migration and invasion and promoted apoptosis by downregulating the Akt pathway in gastric cancer cells, and RAB31 might be a downstream target gene of RAI14, providing a novel sight into the molecular mechanism of RAI14 and a potential target for gastric cancer treatment.
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Colorectal cancer (CRC) is ranked third as the most common malignancy, and it develops into metastasis at a high rate. Importantly, distant metastasis is considered to be a key factor for colorectal therapy. In the present study, we identified FOXD4, a transcription factor belonging to the forkhead/winged helix-box (FOX) family, as a novel biomarker for diagnosis and treatment of patients with CRC. We revealed that FOXD4 was up-regulated in CRC tissues and increased the metastatic ability of CRC cells. Additionally, FOXD4 affected the metastasis of CRC by inducing the epithelial-mesenchymal transition (EMT) process. Furthermore, FOXD4 could directly bind the SNAI3 promoter during EMT in CRC and then facilitate CRC metastasis. In summary, the present research strongly suggests that FOXD4 is a valuable marker for CRC, and that targeting FOXD4 may be a novel strategy for enhancing the treatment outcomes of CRC therapy.
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Colorectal cancer (CRC) is one of the most common malignant gastrointestinal cancers. Metastasis is a major leading of death in patients with CRC and many patients have metastatic disease at diagnosis. However, the underlying molecular mechanisms are still elusive. Here, we showed that JMJD1C was overexpressed in colon cancer tissues compared to normal samples and was positively associated with metastasis and poor prognosis. Silencing JMJD1C strongly inhibits CRC migration and invasion both in vitro and in vivo. Further, we found that knockdown of JMJD1C decreased the protein and mRNA levels of ATF2, mechanistically, and JMJD1C regulated the expression of ATF2 by modulating the H3K9me2 but not H3K9me1 activity. In addition, we further performed some "rescues experiments". We found that overexpression of ATF2 could reverse the abrogated migration and invasion ability by knockdown of JMJD1C in CRC. Our results demonstrated that an increase of JMJD1C was observed in colon cancer and knockdown of JMJD1C regulated CRC metastasis by inactivation of the ATF2 pathway. This novel JMJD1C/ATF2 signaling pathway may be a promising therapeutic target for CRC metastasis.