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Solid polymer electrolytes (SPEs) are promising substitutes for current flammable liquid electrolytes to achieve high-safety and high-energy-density lithium metal batteries. Polyethylene oxide (PEO) based solid polymer electrolytes have attracted increasing attention because of their excellent flexibility, manufacturability, light weight, and low-cost processing, while they often suffer from low ionic conductivity at room temperature, low lithium transference number and unsatisfactory interfacial resistance, which largely restrain their practical application. Herein, two-dimensional holey silica nanosheets (2D-HSN) as the fillers, together with LiNO3as the electrolyte additive, are introduced in a PEO/poly(vinylidene fiuoride-co-hexafluoropropylene) (PVDF-HFP) blended polymer matrix to obtain a SPE. The incorporation of HSN filler creates supplementary channels for lithium ion migration and lowers the crystallinity of the polymer, thereby facilitating the movement of lithium ions. The HSN-based SPE demonstrates higher ionic conductivity up to 3.7 × 10−4 S cm−1at 30 °C, larger Li+transference number close to 0.34, and more stable lithium plating/stripping than that without the fillers, and HSN can promote the formation of more stable solid electrolyte interphase (SEI) layer. The as-assembled LiFePO4||Li batteries deliver a high specific capacity of 159 mA h g−1with the capacity retention of 95.5% after 200 cycles at 30 °C, as well as superior rate performance and cycling stability compared to that using the blank SPE.

Ketone coupling via aldol condensation is one of the promising routes to produce cyclic and value-added precursors for renewable hydrocarbon biofuels. A first-principles-based microkinetic modeling is performed to evaluate the surface-mediated reaction mechanisms and the role of water molecules in the observed activities for 2-pentanone and 3-pentanone aldol condensation on dehydroxylated MgO(111) surface and hydroxylated terminated surface[OH-MgO(111)]. We have identified the enhancement of the surface OH group to MgO(111) surface catalytic activity by destabilizing the binding strength of reaction intermediates and reducing the energy barriers of rate-determining steps(proton transfer and dehydration steps). The 2-pentanone has one elementary step less in the complete reaction mechanism of aldol condensation and preferable energy barrier for proton transfer and dehydration steps, revealing 2-pentanone as terminal ketone is more reactive than 3-pentanone as central ketone. The water molecules dominated the OH-MgO(111) surface after further addition of water, leading to the reduction of turnover frequency of the aldol condensation dimer product as the loss of aldol condensation reaction intermediates in competitive adsorption with water molecules.

The catalytic hydrodeoxygenation (HDO) reaction is of considerable interest for biomass conversion to valuable chemicals and fuels, where one of the critical bottlenecks is the lack of cost-effective and efficient catalysts. To discover cost-efficient catalysts for the HDO reaction, we employed a density functional theory-based hierarchical catalyst design strategy based on catalytic descriptors, reaction energy profiles, and microkinetic modeling (MKM). We focused on the carbide and nitride catalyst space, for which we calculated 121 catalyst surfaces of Mo2C, MoC, Mo2N, W2C, NbC, VC, VN, and NbN catalysts. Based on the computed surface energies, reaction energies of oxygen removal, carbon binding strength, and the surface area of nanoparticles, the likely active facets are the Mo2C(111), MoC(011), VN(100), Mo2N(001), Mo2N(011), and Mo2N(100) surfaces. Further, detailed energy profiles were obtained, and MKM was performed for a model reaction (glycolaldehyde + 2H2→ ethylene + 2H2O) on the Mo2C(111), VN(100), and MoC(100) surfaces. Based on the computed volcano map obtained from MKM, the predicted active facets for this HDO reaction are the Mo2C(111), MoC(011), VN(011), Mo2N(001), Mo2N(011), and Mo2N(100) surfaces. Additionally, none of the carbide and nitride catalyst surfaces are located in the optimal catalytic activity part. Therefore, it is essential to modify the catalyst viaadding dopants or alloying to improve the catalytic activity. Catalytic modifications that can destabilize the surface adsorption of O*/H2O* and decrease the energy barriers of O–H bond formation are recommended to facilitate the HDO on the carbide and nitride catalysts. These a priori investigations provide guidelines for future low-cost HDO catalyst development.

Thyroid cancer is the fastest growing cancer among all solid tumors in recent decades. Papillary thyroid carcinoma (PTC) is the most predominant type of thyroid cancer. Around 30% of PTC patients with distant metastases and local invasion receive poor prognosis. Thus, the identification of new druggable biological targets is of great importance. Accumulating evidence indicates that solute carrier family numbers have emerged as obligate effectors during the progression of multiple malignancies. Here, we uncovered the functional significance, molecular mechanisms, and clinical impact of solute carrier family 34 member A2 (SLC34A2) in PTC. SLC34A2 was markedly overexpressed in PTC tissues at both mRNA and protein levels compared with matched adjacent normal tissues due to promoter hypomethylation mediated by the DNA methyltransferase 3 beta (DNMT3B). Furthermore, a series of in vivo and in vitro gain- or loss-of-functional assays elucidated the role of SLC34A2 in boosting cell proliferation, cell cycle progression, migration, invasion, and adhesion of PTC cells. Using immunoprecipitation and mass spectrometry, we discovered that SLC34A2 bound to the actin-binding repeats domain of Cortactin (CTTN), thereby inducing the invadopodia formation of PTC cells to promote the metastasis potential of PTC cells. Besides, our mechanistic studies, as well as gene set enrichment analysis (GSEA), have pinpointed the PTEN/AKT/FOXO3a pathway as a major signaling functioning downstream of SLC34A2 regulated cell growth. Taken together, our results highlighted that SLC34A2 plays a pivotal oncogenic role during carcinogenesis and metastasis through distinct mechanisms in PTC.

The role of Ni dopant in a molybdenum carbide (Mo2C) catalyst for butadiene and propyne production from furan is investigated by using a Mo2C(001) surface model and first-principles-based microkinetic modeling (MKM). A reaction mechanism including 18 reaction steps is generated to compute the turnover frequency (TOF) of butadiene and propyne from furan gas. The butadiene production is dominant with the TOF being 3–6 orders of magnitude higher than the TOF of propyne on a bare Mo2C surface due to an active C–O bond scission reaction compared to C–C bond cleavage reaction. The exothermic binding of ring-opened furan (CHCHCHCHO*) inhibits the activity of a bare Mo2C surface for butadiene and propyne production. Calculations predict that Mo2C surface modification with a Ni dopant energetically destabilizes the adsorption of CHCHCHCHO*, which facilitates the formation of butadiene and propyne. In the presence of Ni dopants on a Mo2C(001) surface, the selectivity toward the butadiene formation is decreased compared to propyne due to relatively favorable C–C bond scission as opposed to the C–O bond scission. This first-principles-based study provides mechanistic and kinetic insights into the role of dopants in cost-efficient Mo2C catalysts during the vapor phase conversion of furan to gaseous products.

Alpha B-crystallin (CRYAB) is an important member of the small heat shock protein family, and plays a protective and therapeutic role in neurological inflammation. CRYAB expression was assessed in cultured HT29 and Caco-2 cells and inflamed mucosa of patients with inflammatory bowel disease (IBD) and colitis models in mice. Lentivirus-overexpressing and CRSIPR/Cas9 systems were used in different cells to upregulate and silence CRYAB expression, respectively. Cell permeable recombined fusion protein TAT-CRYAB was injected intraperitoneally into dextran sulfate sodium (DSS)- or 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice to assess its anti-inflammatory effects. CRYAB was found to be significantly decreased in the inflamed mucosa from IBD patients and DSS-induced colitis in mice, and negatively correlated with the levels of TNF-α and IL-6, respectively. Enforced expression of CRYAB suppressed expression of proinflammatory cytokines (e.g., TNF-α, IL-6, IL-1β, and IL-8) via inhibiting the IKK complex formation, whereas lack of CRYAB expression markedly enhanced proinflammatory responses. Consistently, administration of TAT-CRYAB fusion protein significantly alleviated DSS- or TNBS-induced colitis in mice and protected intestinal barrier integrity. CRYAB regulates inflammatory response in intestinal mucosa by inhibiting IKKβ-mediated signaling and may serve as a novel therapeutic approach in the treatment of IBD.

Alpha B-crystallin (CRYAB) is an important member of the small heat shock protein family, and plays a protective and therapeutic role in neurological inflammation. CRYAB expression was assessed in cultured HT29 and Caco-2 cells and inflamed mucosa of patients with inflammatory bowel disease (IBD) and colitis models in mice. Lentivirus-overexpressing and CRSIPR/Cas9 systems were used in different cells to upregulate and silence CRYAB expression, respectively. Cell permeable recombined fusion protein TAT-CRYAB was injected intraperitoneally into dextran sulfate sodium (DSS)- or 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice to assess its anti-inflammatory effects. CRYAB was found to be significantly decreased in the inflamed mucosa from IBD patients and DSS-induced colitis in mice, and negatively correlated with the levels of TNF-α and IL-6, respectively. Enforced expression of CRYAB suppressed expression of proinflammatory cytokines (e.g., TNF-α, IL-6, IL-1β, and IL-8) via inhibiting the IKK complex formation, whereas lack of CRYAB expression markedly enhanced proinflammatory responses. Consistently, administration of TAT-CRYAB fusion protein significantly alleviated DSS- or TNBS-induced colitis in mice and protected intestinal barrier integrity. CRYAB regulates inflammatory response in intestinal mucosa by inhibiting IKKβ-mediated signaling and may serve as a novel therapeutic approach in the treatment of IBD.

The furan ring-opening reaction using three catalytic models, HZSM-5, the extra-framework sites [GaO]/ZSM-5, and [Ga(OH)2]/ZSM-5, was investigated using periodic density functional theory as a model reaction for mechanistic understanding of catalytic vapor phase biomass upgrading. The formation of formyl allene from the furan was investigated in detail by computing the energy profiles and reaction barriers. Based on the computed free energy profiles, the HZSM-5 and [Ga(OH)2]/ZSM-5 are active catalysts, whereas [GaO]/ZSM-5 is not active for the furan ring-opening reaction. In HZSM-5, the likely rate-controlling step is furan CH2–O bond cleavage upon protonation (1.70 eV). The computed energy difference between the highest and lowest points in the free energy profile is 1.89 eV. The [Ga(OH)2]+is likely the catalytic center for the gallium-incorporated ZSM-5 catalyst. The rate-controlling step is a hydrogen transfer reaction, which requires a reaction barrier of 2.48 eV. The computed energy difference between the highest and lowest points in the Ga(OH)2catalyzed free energy profile is 2.61 eV. These computational studies provide new mechanistic understanding of the role of catalytic extra-framework sites in the vapor phase upgrading reactions.

Objective Prognostic prediction of colorectal cancer (CRC) remains challenging because of its heterogeneity. Aberrant expression of caudal-type homeobox transcription factor 2 (CDX2) is strongly correlated with the prognosis of CRC.Methods Tissue samples of patients with CRC who underwent surgery in Xinhua Hospital (Shanghai, China) from January 2010 to January 2013 were collected. CDX2 expression was semiquantitatively evaluated via immunohistochemistry.Results In total, 138 patients were enrolled in this study from a prospectively maintained institutional cancer database. The median follow-up duration was 57.5 months (interquartile range, 17.0–71.0 months). In the Cox proportional hazards model, low CDX2 expression combined with stage T4 CRC was significantly the worst prognostic factor for disease-free survival (hazard ratio = 7.020, 95% confidence interval = 3.922–12.564) and overall survival (hazard ratio = 5.176, 95% CI = 3.237–10.091). In the Kaplan–Meier survival analysis, patients with low CDX2 expression and stage T4 CRC showed significantly worse disease-free survival and overall survival than those with low CDX2 expression alone.Conclusion CDX2 expression combined with the T stage was more accurate for predicting the prognosis of CRC. Determining the prognosis of CRC using more than one variable is valuable in developing appropriate treatment and follow-up strategies.

Density functional theory (DFT) calculations were used to investigate the effect of Ni dopants on the removal of chemisorbed oxygen (O*) from the Mo-terminated (TMo) and C-terminated (TC) Mo2C(001) surfaces. The removal of adsorbed oxygen from the catalytic site is essential to maintain the long-term activity and selectivity of the carbide catalysts in the deoxygenation process related to bio-oil stabilization and upgrading. In this contribution, the computed reaction energetics and reaction barriers of O* removal were compared among undoped and Ni-doped Mo2C(001) surfaces. The DFT calculations indicate that selected Ni-doped surfaces such as Ni adsorbed on TMoand TCMo2C(001) surfaces enable weaker binding of important reactive intermediates (O*, OH*) compared to the undoped counterparts, which is beneficial for the O* removal from the catalyst surface. This study thus confirms the promoting effect of the Ni dopant on O* removal reaction on the TMoMo2C(001) and TCMo2C(001) surfaces. This computational prediction has been confirmed by the temperature-programmed reduction profiles of Mo2C and Ni-doped Mo2C catalysts, which had been passivated and stored in an oxygen environment.

The practical application of high-energy-density lithium-sulfur (Li-S) batteries have been highly praised for energy storage devices, while are largely hindered by the “shuttling effect”. Herein, core-shell carbon spheres composed of interlinked porous core and lamellar shell were designed to restrain the polysulfide shuttling. The microporous structure with pore size of around 1 nm effectively trap lithium polysulfides. Furthermore, the interconnected porous core shortens the ion transfer distance and the lamellar carbon shell endows the carbon spheres with fast electron conduction, finally facilitating polysulfide conversion kinetics. Therefore, the Li-S batteries with the carbon spheres as the interlayer show high discharge specific capacity of 1002 mAh/g at 2 C with 574 mAh/g remaining after 600 cycles, and high areal capacity of 5.48 mAh/cm2with sulfur loading of 4.67 mg/cm2at 0.1 C. The corresponding pouch cells also exhibit stable cycling stability with an initial discharge specific capacity of 1082 mAh/g at 0.1 C.

Additive manufacturing (AM) technology has been widely used in the aerospace, automotive, and healthcare industries over the last few decades. However, the dependability of AM process in producing high-quality manufactured goods remains an open and challenging task. To address this challenge, this study presents a data-driven predictive model based on multiple machine learning algorithms for Fused Deposition Modeling (FDM) process. Temperature and vibration data from multiple sensors (thermocouples, infrared thermometers, and accelerometers) are collected and divided to extract the time-frequency feature accordingly. Then, the sensing data and process parameters are fused to predict dimensional deviations between the printed model and the original one. To quantify the importance of different process parameters and sensing data, a sensitivity analysis experiment is performed on the training data. Experimental evaluation has shown that the prediction model based on the Residual Attention neural network outperforms other machine learning models, such as 1D Convolutional Neural Network and Convolutional Neural & Long Short-Term Memory Network. The proposed robust model can improve the quality assurance of additive manufacturing in practice after optimization.

Through polarization and spectra analysis of the magnetic field observed by the Van Allen Probe A, we present two typical cases of O+band electromagnetic ion cyclotron (EMIC) waves in the outer plasmasphere or plasma trough. Although such O+band EMIC waves are rarely observed, 18 different events of O+band EMIC waves (16 events in the outer plasmasphere and two events in the plasma trough) are found from September 2012 to August 2014 with observations of the Van Allen Probe A. We find that the preferred region for the occurrence of O+band EMIC waves is in L= 2–5 and magnetic local time  = 03–13, 19–20, which is in accordance with the occurrence region of O+ion torus. Therefore, our result suggests that the O+ion torus in the outer plasmasphere during geomagnetic activities should play an important role in the generation of EMIC waves in O+band. In situ evidence to EMIC waves in O+bandPreferred occurrence region for EMIC waves in O+bandEMIC waves in the plasma of multiple ions

Highly reversible Mg plating/stripping is key for rechargeable Mg batteries and has typically been successfully demonstrated using transient electrochemical techniques such as cyclic voltammetry measurements. However, little effort has been invested in studying the stability of the electrode/electrolyte interface over an extended time. We report here the development of an in situ generated surface film for Mg anodes based on electrodeposited bismuth (E_Bi). This film improves the interfacial stability of Mg in contact with the electrolyte, particularly over an extended time, and possesses fast charge-transfer kinetics (<30 Ω∙cm2) and low non-time-sensitive interfacial film resistance (ca. 5 Ω∙cm2) for active Mg species.

Growing evidence indicates that N6-methyladenosine (m6A) is the most pervasive RNA modification in eukaryotic cells. However, the specific role of METTL3 in papillary thyroid carcinoma (PTC) initiation and development remains elusive. Here we found that downregulation of METTL3 was correlated with malignant progression and poor prognosis in PTC. A variety of gain- and loss-of-function studies clarified the effect of METTL3 on regulation of growth and metastasis of PTC cells in vitroand in vivo. By combining RNA sequencing (RNA-seq) and methylated RNA immunoprecipitation sequencing (meRIP-seq), our mechanistic studies pinpointed c-Rel and RelA as downstream m6A targets of METTL3. Disruption of METTL3 elicited secretion of interleukin-8 (IL-8), and elevated concentrations of IL-8 promoted recruitment of tumor-associated neutrophils (TANs) in chemotaxis assays and mouse models. Administration of the IL-8 antagonist SB225002 substantially retarded tumor growth and abolished TAN accumulation in immunodeficient mice. Our findings revealed that METTL3 played a pivotal tumor-suppressor role in PTC carcinogenesis through c-Rel and RelA inactivation of the nuclear factor κB (NF-κB) pathway by cooperating with YTHDF2 and altered TAN infiltration to regulate tumor growth, which extends our understanding of the relationship between m6A modification and plasticity of the tumor microenvironment.

The reaction mechanism of non-aqueous Li-O2batteries is based on the deposition and decomposition of Li2O2. The polarization of Li-O2batteries can be rapidly increased by operation under a high rate condition, resulting in the early capacity fade of the cells. Therefore, a well-designed catalyst with a unique structure and excellent catalytic ability is an important way to boost the round-trip performance of Li-O2batteries, especially under high current density. In this work, a unique nanoflower structure assembled with Co3O4nanosheets is synthesized by using 2-methylimidazole (2-MIM) as a structural directing agent. X-ray photoelectron spectroscopy (XPS) and Raman spectra reveal abundant oxygen vacancies on the surface of the Co3O4nanoflower, which are beneficial for oxygen reduction and evolution reactions and long round-trip lifetime. Density functional theory results demonstrate that Co3O4catalyst with oxygen vacancies could promote the wetting of Li2O2on substrate and formation of a Li2O2nanofilm, thereby boosting the discharge capacity of Li-O2batteries. On account of the synergistic effect of abundant oxygen vacancies, the unique structure, and excellent oxygen evolution reaction, Co3O4nanoflower-based cells could deliver ultralong lifetime of 276 and 248 cycles with a discharge capacity of 1000 mAh g−1under charge/discharge current densities of 0.5 A g−1and 1 A g−1, respectively. This study has shed light on a new strategy for catalyst preparation for long lifetime Li-O2batteries.