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Colloidal properties of nanoparticles are intricately linked to their morphology. Traditionally, achieving high-concentration dispersions of two-dimensional (2D) nanosheets has proven challenging as they tend to agglomerate or re-stack under increased surface contact and Van der Waals attraction. Here, we unveil an excluded volume effect enabled by 2D morphology, which can be coupled with electrostatic repulsion to synthesize high-concentration aqueous graphene dispersions. To achieve this, we designed a sequential process involving edge oxidation, bubble expansion and mechanical shearing, through which graphite flakes were exfoliated into aqueous dispersions with ~94.5 wt.% yield of few-layer graphene, high concentration exceeding 100 mg mL -1 , long-term stability over ~550 days, and large-scale wet processability. Structural analysis and theoretical modeling suggested that the 2D morphology of the resultant graphene nanosheets facilitates inter-sheet repulsive excluded volume interactions, leading to a fractal jammed network structure composed of nanosheets and tactoids to prevent their agglomeration. This effect was further leveraged in a continuous stirred tank reactor for the pilot-scale production of concentrated graphene dispersions. Our study unveils the role of excluded volume effect in stabilizing 2D-material colloids for industrial production and processing., Competing Interests: Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Colloidal clusters with well-controlled shapes have attracted extensive interest in the fields of materials, chemistry, physics, and biology. This communication reports the controllable fabrication of photoresponsive colloidal clusters with a wide range of adjustable sizes and complex architectures through an approach of microsphere formation and fusion. The clusters of colloidal spheres were obtained via adding ethanol dropwise into a tetrahydrofuran solution of an isosorbide-based azo compound (IAC-4). In the process, the colloidal spheres with soft and sticky shells were first formed in the dispersion. After stirring at an appropriate rate and time, clusters composed of controlled numbers of colloidal spheres were obtained. With increasing stirring time, the colloidal spheres in the clusters underwent fusion transforming into a range of structures with particular architectures. The structure formation, evolution and control were investigated by scanning electron microscopy (SEM) and dynamic light scattering (DLS). Under linearly polarized light irradiation, colloidal spheres in the clusters in the solid state were observed to be stretched along the direction of electric-field oscillation and these clusters were thus transformed into complex particles with unique morphologies. This exploration can lead to a new methodology to effectively fabricate colloidal clusters with complex architectures and shed new light on colloidal packing and organization under the driving forces of extrinsic energy input.

Two-dimensional materials with ultrahigh in-plane thermal conductivity are ideal for heat spreader applications but cause significant thermal contact resistance in complex interfaces, limiting their use as thermal interface materials. In this study, we present an interfacial phonon bridge strategy to reduce the thermal contact resistance of boron nitride nanosheets-based composites. By using a low-molecular-weight polymer, we are able to manipulate the alignment of boron nitride nanosheets through sequential stacking and cutting, ultimately achieving flexible thin films with a layer of arc-like structure superimposed on perpendicularly aligned ones. Our results suggest that arc-like structure can act as a phonon bridge to lower the contact resistance by 70% through reducing phonon back-reflection and enhancing phonon coupling efficiency at the boundary. The resulting composites exhibit ultralow thermal contact resistance of 0.059 in 2 KW -1 , demonstrating effective cooling of fast-charging batteries at a thickness 2-5 times thinner than commercial products., (© 2024. The Author(s).)

Deleted in breast cancer 1 (DBC1) is a human nuclear protein that modulates the activities of various proteins involved in cell survival and cancer progression. Oxidized form of nicotinamide adenine dinucleotide (NAD + ) is suggested to bind to the Nudix homology domains (NHDs) of DBC1, thereby regulating DBC1-Poly (ADP-ribose) polymerase 1 (PARP1) interactions, resulting in the restoration of DNA repair. Using Nuclear Magnetic Resonance (NMR) and Isothermal Titration Calorimetry (ITC), we confirmed NAD + and its precursor nicotinamide mononucleotide (NMN) both bind the NHD domain of DBC1 (DBC1 354 - 396 ). NAD + likely interacts with DBC1 354 - 396 through hydrogen bonding, with a binding affinity (8.99 μM) nearly twice that of NMN (17.0 μM), and the key binding sites are primarily residues E363 and D372, in the agreement with Molecular Docking experiments. Molecular Dynamics (MD) simulation further demonstrated E363 and D372's anchoring role in the binding process. Additional mutagenesis experiments of E363 and D372 confirmed their critical involvement of ligand-protein interactions. These findings lead to a better understanding of how NAD + and NMN regulate DBC1, thereby offering insights for the development of targeted therapies and drug research focused on DBC1-associated tumors., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Hexagonal boron nitride nanosheets (BNNSs) exhibit remarkable thermal and dielectric properties. However, their self-assembly and alignment in macroscopic forms remain challenging due to the chemical inertness of boron nitride, thereby limiting their performance in applications such as thermal management. In this study, we present a coaxial wet spinning approach for the fabrication of BNNSs/polymer composite fibers with high nanosheet orientation. The composite fibers were prepared using a superacid-based solvent system and showed a layered structure comprising an aramid core and an aramid/BNNSs sheath. Notably, the coaxial fibers exhibited significantly higher BNNSs alignment compared to uniaxial aramid/BNNSs fibers, primarily due to the additional compressive forces exerted at the core-sheath interface during the hot drawing process. With a BNNSs loading of 60 wt%, the resulting coaxial fibers showed exceptional properties, including an ultrahigh Herman orientation parameter of 0.81, thermal conductivity of 17.2 W m -1  K -1 , and tensile strength of 192.5 MPa. These results surpassed those of uniaxial fibers and previously reported BNNSs composite fibers, making them highly suitable for applications such as wearable thermal management textiles. Our findings present a promising strategy for fabricating high-performance composite fibers based on BNNSs., (© 2023. The Author(s).)

Ion adsorption within nanopores is involved in numerous applications. However, a comprehensive understanding of the fundamental relationship between in-pore ion concentration and pore size, particularly in the sub-2 nm range, is scarce. This study investigates the ion-species-dependent concentration in multilayered graphene membranes (MGMs) with tunable nanoslit sizes (0.5-1.6 nm) using nuclear magnetic resonance and computational simulations. For Na + -based electrolytes in MGMs, the concentration of anions in graphene nanoslits increases in correlation with their chaotropic properties. As the nanoslit size decreases, the concentration of chaotropic ion (BF 4 - ) increases, whereas the concentration of kosmotropic ions (Cit 3- , PO 4 3- ) and other ions (Ac - , F - ) decreases or changes slightly. Notably, anions remain more concentrated than counter Na + ions, leading to electroneutrality breakdown and unipolar anion packing in MGMs. A continuum modeling approach, integrating molecular dynamic simulation with the Poisson-Boltzmann model, elucidates these observations by considering water-mediated ion-graphene non-electrostatic interactions and charge screening from graphene walls.

While photoluminescent graphene quantum dots (GQDs) have long been considered very suitable for bioimaging owing to their protein-like size, superhigh photostability and in vivo long-term biosafety, their unique and crucial bioimaging applications in vivo remain unreachable. Herein, planted GQDs are presented as an excellent tool for in vivo fluorescent, sustainable and multimodality tumor bioimaging in various scenarios. The GQDs are in situ planted in the poly(ethylene glycol) (PEG) layer of PEGylated nanoparticles via a bottom-up molecular approach to obtain the NPs-GQDs-PEG nanocomposite. The planted GQDs show more than four times prolonged blood circulation and 7-8 times increased tumor accumulation than typical GQDs in vivo. After accessible specificity modification, the multifunctional NPs-GQDs-PEG provides targeted, multimodal molecular imaging for various tumor models in vitro or in vivo. Moreover, the highly photostable GQDs enable long-term, real-time visualization of the local pharmacokinetics of NPs in vivo. Planting GQDs in PEGylated nanomedicine offers a new strategy for broad in vivo biomedical applications of GQDs., (© 2023 Wiley-VCH GmbH.)

Assembling two-dimensional (2D) nanomaterials into laminar membranes with a subnanometer (subnm) interlayer spacing provides a material platform for studying a range of nanoconfinement effects and exploring the technological applications related to the transport of electrons, ions and molecules. However, the strong tendency for 2D nanomaterials to restack to their bulk crystalline-like structure makes it challenging to control their spacing at the subnm scale. It is thus necessary to understand what nanotextures can be formed at the subnm scale and how they can be engineered experimentally. In this work, with dense reduced graphene oxide membranes as a model system, we combine synchrotron-based X-ray scattering and ionic electrosorption analysis to reveal that their subnanometric stacking can result in a hybrid nanostructure of subnm channels and graphitized clusters. We demonstrate that the ratio of these two structural units, their sizes and connectivity can be engineered by stacking kinetics through the reduction temperature to allow the realization of high-performance compact capacitive energy storage. This work highlights the great complexity of subnm stacking of 2D nanomaterials and provides potential methods to engineer their nanotextures at will.

Background: To develop and validate an MRI texture-based machine learning model for the noninvasive assessment of renal function., Methods: A retrospective study of 174 diabetic patients (training cohort, n = 123; validation cohort, n = 51) who underwent renal MRI scans was included. They were assigned to normal function (n = 71), mild or moderate impairment (n = 69), and severe impairment groups (n = 34) according to renal function. Four methods of kidney segmentation on T2-weighted images (T2WI) were compared, including regions of interest covering all coronal slices (All-K), the largest coronal slices (LC-K), and subregions of the largest coronal slices (TLCO-K and PIZZA-K). The speeded-up robust features (SURF) and support vector machine (SVM) algorithms were used for texture feature extraction and model construction, respectively. Receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic performance of models., Results: The models based on LC-K and All-K achieved the nonsignificantly highest accuracy in the classification of renal function (all p values > 0.05). The optimal model yielded high performance in classifying the normal function, mild or moderate impairment, and severe impairment, with an area under the curve of 0.938 (95% confidence interval [CI] 0.935-0.940), 0.919 (95%CI 0.916-0.922), and 0.959 (95%CI 0.956-0.962) in the training cohorts, respectively, as well as 0.802 (95%CI 0.800-0.807), 0.852 (95%CI 0.846-0.857), and 0.863 (95%CI 0.857-0.887) in the validation cohorts, respectively., Conclusion: We developed and internally validated an MRI-based machine-learning model that can accurately evaluate renal function. Once externally validated, this model has the potential to facilitate the monitoring of patients with impaired renal function., (© 2023. The Author(s).)

The electrical and biological interfacial properties of invasive electrodes have a significant impact on the performance and longevity of neural recordings in the brain. In this study, we demonstrated rapid electrophoretic deposition and electrochemical reduction of graphene oxide (GO) on metal-based neural electrodes. Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and other characterizations confirmed the existence of a uniform and effectively reduced graphene oxide coating. Electrochemically reduced graphene oxide (ErGO) coated Pt/Ir neural electrodes exhibited 15.2-fold increase in charge storage capacity (CSC) and 90% decrease in impedance with only 3.8% increase in electrode diameter. Patch clamp electrophysiology and calcium imaging of primary rat hippocampus neurons cultured on ErGO demonstrated that there was no adverse impact on the functional development of neurons. Immunostaining showed a balanced growth of excitatory and inhibitory neurons, and astrocytes. Acute recordings from the auditory cortex and chronic recordings (19 days) from the somatosensory cortex found ErGO coating improved the performance of neural electrodes in signal-to-noise ratio (SNR) and amplitude of signals. The proposed approach not only provides an in-depth evaluation of the effect of ErGO coating on neural electrodes but also widens the coating methods of commercial neural electrodes.

Purpose: Accurate identification of nodal status enables adequate neck irradiation for nasopharyngeal carcinoma (NPC). However, most conventional techniques are unable to pick up occult metastases, leading to underestimation of tumor extensions. Here we investigate the clinical significance of carbonic anhydrase IX (CAIX) in human NPC samples, and develop a CAIX-targeted imaging strategy to identify occult lymph node metastases (LNMs) and extranodal extension (ENE) in animal studies., Methods: A total of 211 NPC samples are performed CAIX staining, and clinical outcomes are analyzed. The metastatic murine models are generated by foot pad injection of NPC cells, and a CAIX-targeted imaging agent (CAIX-800) is intravenously administered. We adopt fluorescence molecular tomography and ultrasonography (US)-guided spectroscopic photoacoustic (sPA) imaging to perform in vivo studies. Histological and immunohistochemical characterization are carried out via node-by-node analysis., Results: For clinical samples, 90.1% (91/101) primary tumors, 73.3% (66/90) metastases, and 100% (20/20) local recurrences are CAIX positive. In metastases group, 84.7% (61/72) nodal metastases and 22.2% (4/18) organ metastases are CAIX positive. CAIX expression in primary tumors is significantly associated with NPC stage and prognosis. For animal studies, CAIX-800-based fluorescence imaging achieves 81.3% sensitivity and 93.8% specificity in detecting occult LNMs in vivo, with a minimum detectable diameter of 1.7 mm. Coupled with CAIX-800, US-guided sPA imaging could not only detect subcapsular deposits of metastatic cancer cells 2 weeks earlier than conventional techniques, but also successfully track pathological ENE., Conclusion: CAIX remarkably expresses in human NPCs and stratifies patient prognosis. In preclinical studies, CAIX-800-based imaging successfully identifies occult LNMs and tracks early stage of pathological ENE. This attractive method shows potential in clinic, allowing medical workers to longitudinally monitor nodal status and helping to reduce unnecessary nodal biopsy for patients with NPC. The schematic diagram for the study. CAIX, carbonic anhydrase IX; NPC, nasopharyngeal carcinoma; US, ultrasonography; sPA, spectroscopic photoacoustic., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The recent emergence of electrically conductive nanoporous membranes based on graphene and other 2D materials opens up new opportunities to revisit some longstanding nanoconfined ion transport problems under electrification. This work probes the ionic resistance in electrified multilayered graphene membranes with electrochemical impedance spectroscopy. This study demonstrates that the combination of additive-free feature and tunable slit pore sizes in the sub-10 nm range in graphene-based membranes has made it possible to deconvolute the different ionic processes from the impedance obtained and examine the exclusive influence of pore size on the ionic resistance in a quantitative manner. The trends revealed for the ionic resistance at the pore entrance and inside the pores under severe nanoconfinement (<2 nm) are found to be generally consistent with the microscale theoretical simulations previously reported. It also allows a quantitative analysis of the relative effects of the external polarization potential and ion identity under nanoconfinement. The results suggest that the classic electrochemical impedance spectroscopy technique, when applied to appropriate nanoporous electrode materials, can provide rich information about nanoconfined ion transport phenomena under electrification for fundamental understanding and application development., (© 2022 The Authors. Small Methods published by Wiley-VCH GmbH.)

Tumour recurrence and drug resistance in hepatocellular carcinoma remain challenging. Cancer stem cells (CSCs) are responsible for tumour initiation because of their stemness characteristics. CSCs accounting for drug resistance and tumour relapse are promising therapeutic targets. We report that Abelson interactor 2 (ABI2) is a novel therapeutic target of HCC CSCs. First, ABI2 was upregulated in HCC tissues compared with liver tissues and was associated with tumour size, pathological grade, liver cirrhosis, worse prognosis and a high recurrence rate. Functional studies illustrate that ABI2 knockdown suppresses cell growth, migration, invasion and sorafenib resistance in vitro. Furthermore, ABI2 knockdown inhibited HCC sphere formation and decreased the CD24 + , CD133 + and CD326 + CSCs populations, suggesting the suppression of HCC stemness characteristics. A tumour xenograft model and limiting dilution assay demonstrated the inhibition of tumorigenicity and tumour initiation. Moreover, molecular mechanism studies showed that ABI2 recruits and directly interacts with the transcription factor MEOX2, which binds to the KLF4 and NANOG promoter regions to activate their transcription. Furthermore, overexpression of MEOX2 restored HCC malignant behaviour and the CSC population. The ABI2-mediated transcriptional axis MEOX2/KLF4-NANOG promotes HCC growth, metastasis and sorafenib resistance by maintaining the CSC population, suggesting that ABI2 is a promising CSC target in HCC treatment., (© 2022 The Authors. Liver International published by John Wiley & Sons Ltd.)

Traumatic bone marrow lesions (TBMLs) are considered to represent a range of concealed bone injuries, including haemorrhage, infarction, and localised oedema caused by trabecular microfracture occurring in the cancellous bone. If TBMLs are not managed timeously, they potentially cause a series of complications that can lead to irreversible morbidity and prolonged recovery time. This article reviews interesting image findings of bone marrow lesions in dual-energy computed tomography (DECT). In addition to combining the benefits of traditional CT imaging, DECT also reveals and identifies various structures using diverse attenuation characteristics of different radiographic spectra. Therefore, DECT has the capacity to detect TBMLs, which have traditionally been diagnosed using MRI. Through evaluating DECT virtual non-calcium maps, the detection of TBMLs is rendered easier and more efficient in some acute accidents., (© 2022. The Author(s).)

Eardrum perforation and associated hearing loss is a global health problem. Grafting perforated eardrum with autologous tissues in clinic can restore low-frequency hearing but often leaves poor recovery of high-frequency hearing. In this study, the potential of incorporating a thin multilayered graphene membrane (MGM) into the eardrum for broadband hearing recovery in rats is examined. The MGM shows good biocompatibility and biostability to promote the growth of eardrum cells in a regulated manner with little sign of tissue rejection and inflammatory response. After three weeks of implantation, the MGM is found to be encapsulated by a thin layer of newly grown tissue on both sides without a significant folded overgrowth that is often seen in natural healing. The perforation is well sealed, and broadband hearing recovery (1-32 kHz) is enabled and maintained for at least 2 months. Mechanical simulations show that the high elastic modulus of MGM and thin thickness of the reconstructed eardrum play a critical role in the recovery of high-frequency hearing. This work demonstrates the promise of the use of MGM as a functional graft for perforated eardrum to recover hearing in the broadband frequency region and suggests a new acoustics-related medical application for graphene-related 2D materials., (© 2022 The Authors. Advanced Healthcare Materials published by Wiley-VCH GmbH.)

Objectives: To investigate the effects of transcatheter arterial chemoembolization (TACE) combined with radiofrequency ablation (RFA) on liver function and immune function in patients with hepatocellular carcinoma (HCC)., Methods: From December 2016 to January 2019, patients with primary liver cancer who could not be operated on were selected as the study subjects. 170 patients were randomly divided into two groups. The control group was treated with transcatheter arterial chemoembolization ( n  = 85). The patients in the observation group were treated with transcatheter arterial chemoembolization combined with radiofrequency ablation ( n  = 85). The clinical effects of the two groups were analyzed. The changes of liver function and immune function were detected by automatic biochemical analyzer before and after treatment. The changes of hypoxia inducible factor-1 (HIF1) alpha and vascular endothelial growth factor (VEGF) levels before and after treatment were analyzed by enzyme-linked immunosorbent assay (ELISA)., Results: The total effective rate in the observation group was significantly higher than that in the control group ( P < 0.05). After treatment, serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), CD8+, HIF1 alpha, and VEGF decreased significantly ( P < 0.05), while levels of total bilirubin, direct bilirubin, indirect bilirubin, CD3+, CD4+, and CD4+/CD8+ increased significantly ( P < 0.05). The changes of the above indexes in the observation group were more significant than those in the control group ( P < 0.05)., Conclusion: Hepatic arterial chemoembolization combined with radiofrequency ablation has a significant effect on liver function and immune function in patients with liver cancer, which may be related to the abnormal levels of HIF1 α and vascular endothelial growth factor., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as potential conflicts of interest., (Copyright © 2022 Yan Zhou et al.)

Background: Transcatheter arterial chemoembolization (TACE) is the mainstay of therapy for intermediate-stage hepatocellular carcinoma (HCC); yet its efficacy varies between patients with the same tumor stage. Accurate prediction of TACE response remains a major concern to avoid overtreatment. Thus, we aimed to develop and validate an artificial intelligence system for real-time automatic prediction of TACE response in HCC patients based on digital subtraction angiography (DSA) videos via a deep learning approach., Methods: This retrospective cohort study included a total of 605 patients with intermediate-stage HCC who received TACE as their initial therapy. A fully automated framework (i.e., DSA-Net) contained a U-net model for automatic tumor segmentation (Model 1) and a ResNet model for the prediction of treatment response to the first TACE (Model 2). The two models were trained in 360 patients, internally validated in 124 patients, and externally validated in 121 patients. Dice coefficient and receiver operating characteristic curves were used to evaluate the performance of Models 1 and 2, respectively., Results: Model 1 yielded a Dice coefficient of 0.75 (95% confidence interval [CI]: 0.73-0.78) and 0.73 (95% CI: 0.71-0.75) for the internal validation and external validation cohorts, respectively. Integrating the DSA videos, segmentation results, and clinical variables (mainly demographics and liver function parameters), Model 2 predicted treatment response to first TACE with an accuracy of 78.2% (95%CI: 74.2-82.3), sensitivity of 77.6% (95%CI: 70.7-84.0), and specificity of 78.7% (95%CI: 72.9-84.1) for the internal validation cohort, and accuracy of 75.1% (95% CI: 73.1-81.7), sensitivity of 50.5% (95%CI: 40.0-61.5), and specificity of 83.5% (95%CI: 79.2-87.7) for the external validation cohort. Kaplan-Meier curves showed a significant difference in progression-free survival between the responders and non-responders divided by Model 2 (p = 0.002)., Conclusions: Our multi-task deep learning framework provided a real-time effective approach for decoding DSA videos and can offer clinical-decision support for TACE treatment in intermediate-stage HCC patients in real-world settings., (© 2022. The Author(s).)

Stiffness and viscoelasticity of neural implants regulate the foreign body response. Recent studies have suggested the use of elastic or viscoelastic materials with tissue-like stiffness for long-term neural electrical interfacing. Herein, the authors find that a viscoelastic multilayered graphene hydrogel (MGH) membrane, despite exhibiting a much higher Young's modulus than nerve tissues, shows little inflammatory response after 8-week implantation in rat sciatic nerves. The MGH membrane shows significant viscoelasticity due to the slippage between graphene nanosheets, facilitating its seamless yet minimally compressive interfacing with nerves to reduce the inflammation caused by the stiffness mismatch. When used as neural stimulation electrodes, the MGH membrane can offer abundant ion-accessible surfaces to bring a charge injection capacity 1-2 orders of magnitude higher than its traditional Pt counterpart, and further demonstrates chronic neural therapy potential in low-voltage modulation of rat blood pressure. This work suggests that the emergence of 2D nanomaterials and particularly their unique structural attributes can be harnessed to enable new bio-interfacing design strategies., (© 2022 The Authors. Small Methods published by Wiley-VCH GmbH.)

Objectives: To develop and validate a radiomic model to predict the rapid progression (defined as volume growth of pneumonia lesions > 50% within seven days) in patients with coronavirus disease 2019 (COVID-19)., Methods: Patients with laboratory-confirmed COVID-19 who underwent longitudinal chest CT between January 01 and February 18, 2020 were included. A total of 1316 radiomic features were extracted from the lung parenchyma window for each CT. The least absolute shrinkage and selection operator (LASSO), Relief, Las Vegas Wrapper (LVW), L1-norm-Support Vector Machine (L1-norm-SVM), and recursive feature elimination (RFE) were applied to select the features that associated with rapid progression. Four machine learning classifiers were used for modeling, including Support Vector Machine (SVM), Random Forest (RF), Logistic Regression (LR), and Decision Tree (DT). Accordingly, 20 radiomic models were developed on the basis of 296 CT scans and validated in 74 CT scans. Model performance was determined by the receiver operating characteristic curve., Results: A total of 107 patients (median age, 49.0 years, interquartile range, 35-54) were evaluated. The patients underwent a total of 370 chest CT scans with a median interval of 4 days (interquartile range, 3-5 days). The combination methods of L1-norm SVM and SVM with 17 radiomic features yielded the highest performance in predicting the likelihood of rapid progression of pneumonia lesions on next CT scan, with an AUC of 0.857 (95% CI: 0.766-0.947), sensitivity of 87.5%, and specificity of 70.7%., Conclusions: Our radiomic model based on longitudinal chest CT data could predict the rapid progression of pneumonia lesions, which may facilitate the CT follow-up intervals and reduce the radiation., Advances in Knowledge: Radiomic features extracted from the current chest CT have potential in predicting the likelihood of rapid progression of pneumonia lesions on the next chest CT, which would improve clinical decision-making regarding timely treatment.

Graphene-based nanoporous materials have been extensively explored as high-capacity ion electrosorption electrodes for supercapacitors. However, little attention has been paid to exploiting the interactions between electrons that reside in the graphene lattice and the ions adsorbed between the individual graphene sheets. Here we report that the electronic conductance of a multilayered reduced graphene oxide membrane, when used as a supercapacitor electrode, can be modulated by the ionic charging state of the membrane, which gives rise to a collective electrolyte gating effect. This gating effect provides an in-operando approach for probing the charging dynamics of supercapacitors electrically. Using this approach, we observed a pore-size-dependent ionic hysteresis or memory effect in reduced graphene oxide membranes when the interlayer distance is comparable to the ion diameter. Our results may stimulate the design of novel devices based on the ion-electron interactions under nanoconfinement.

Restacking of 2D nanomaterials is often deemed to be detrimental to their applications. In contrast to this common notion, here we demonstrate that tightly packed stacked MoS2 exhibits a higher electrocatalytic activity for hydrogen evolution than the more loosely stacked ones.

A new class of robust superhydrophobic cotton fabric was prepared by chemically grafting method for removing oil from contaminated waters. Furthermore, the mechanical, chemical, and thermal durability of superhydrophobic cotton fabric was evaluated in detail. The superhydrophobic cotton fabric did not only showed excellent separation efficiency (ca.100%) and ultrafast separation rate (ca. 13,600 L/h m 2 ) but also exhibited excellent durability. Especially, the oil/water separation rate was almost 10 times than that reported in previous works. The work provides a new method to design and large-scale prepare oil/water separation materials with high performance for industrial use.

Nanoporous laminar membranes composed of multilayered 2D nanomaterials (2D-NLMs) are increasingly being exploited as a unique material platform for understanding solvated ion transport under nanoconfinement and exploring novel nanoionics-related applications, such as ion sieving, energy storage and harvesting, and in other new ionic devices. Here, the fundamentals of solvation-involved nanoionics in terms of ionic interactions and their effect on ionic transport behaviors are discussed. This is followed by a summary of key requirements for materials that are being used for solvation-involved nanoionics research, culminating in a demonstration of unique features of 2D-NLMs. Selected examples of using 2D-NLMs to address the key scientific problems related to nanoconfined ion transport and storage are then presented to demonstrate their enormous potential and capabilities for nanoionics research and applications. To conclude, a personal perspective on the challenges and opportunities in this emerging field is presented., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Purpose: Accurate evaluation of hypoxia is particularly important in patients with nasopharyngeal carcinoma (NPC) undergoing radiotherapy. The aim of this study was to propose a novel imaging strategy for quantitative three-dimensional (3D) evaluation of hypoxia in a small animal model of NPC., Methods: A carbonic anhydrase IX (CAIX)-specific molecular probe (CAIX-800) was developed for imaging of hypoxia. Mouse models of subcutaneous, orthotopic, and spontaneous lymph node metastasis from NPC (5 mice per group) were established to assess the imaging strategy. A multi-modality imaging method that consisted of a hybrid combination of fluorescence molecular tomography-computed tomography (FMT-CT) and multispectral optoacoustic tomography (MSOT) was used for 3D quantitative evaluation of tumour hypoxia. Magnetic resonance imaging, histological examination, and immunohistochemical analysis were used as references for comparison and validation., Results: In the early stage of NPC (2 weeks after implantation), FMT-CT enabled precise 3D localisation of the hypoxia biomarker with high sensitivity. At the advanced stage (6 weeks after implantation), MSOT allowed multispectral analysis of the biomarker and haemoglobin molecules with high resolution. The combination of high sensitivity and high resolution from FMT-CT and MSOT could not only detect hypoxia in small-sized NPCs but also visualise the heterogeneity of hypoxia in 3D., Conclusions: Integration of FMT-CT and MSOT could allow comprehensive and quantifiable evaluation of hypoxia in NPC. These findings may potentially benefit patients with NPC undergoing radiotherapy in the future. Graphical abstract A novel multimodality imaging strategy for three-dimensional evaluation of tumour hypoxia in an orthotopic model of nasopharyngeal carcinoma.

In this work, reduced graphene oxide (RGO) was used as a material to fabricate superhydrophobic lotus-leaf-like surfaces through soft-lithographic duplication. In the process, a polydimethylsiloxane (PDMS) stamp was prepared by replica molding against the surfaces of fresh lotus leaves that functioned as masters. A dispersion of octadecylamine-modified reduced graphene oxide (ODA-RGO) in tetrahydrofuran (THF) was used as "ink". The lotus-leaf-like surfaces were fabricated by microcontact printing on the solid substrates. The results showed that due to the good processibility of the ODA-RGO dispersion, the printed layers display papillary micro/nano-structures with high fidelity to the surfaces of lotus leaves. The RGO-based lotus-leaf-like surfaces possess superhydrophobic characteristics with a water contact angle larger than 160° and the contact angle hysteresis less than 5°. Due to the excellent chemical stability of the RGO sheets, as-prepared surfaces show remarkable superhydrophobic stability. The lotus-leaf-like surfaces maintain the superhydrophobicity after heating treatment at 150 °C for 24 h or being exposed to corrosive solutions with different pH values for 12 h. The present findings prove that the RGO-based material is an ideal candidate for fabrication of environment-durable lotus-leaf-like surfaces, which can be expected to have applications in different areas., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

A series of polymers containing nunchaku-like unit with an azo chromophore and a mesogen group was successfully prepared and photoinduced anisotropy of the obtained polymers was minutely investigated. Firstly, monomers containing nunchaku-like unit with an azo chromophore and a mesogen group linked by flexible group were synthesized. The structure of the monomers was confirmed via NMR COSY spectra. Subsequently, the obtained monomers were polymerized into corresponding polymers through RAFT polymerization. The prepared polymer samples were characterized through NMR, FTIR, gel permeation chromatography (GPC), and UV-vis testing while the thermal properties of the samples were investigated through differential scanning calorimeter (DSC) and thermogravimetric analysis (TGA) measurements. The photoinduced isomerization of the polymers, which was researched in situ via measuring UV-vis spectra of the polymer solutions and spin-coated films under irradiation with 450 nm light or putting in darkness, demonstrated the rapid trans - cis - trans isomerization of the polymers. When irradiated with a linearly polarized light, significant photoinduced birefringence and dichroism were observed, suggesting photoinduced isomerization of azobenzene can drive orientation of mesogen in the system. This study blazes a way to design the optical materials with light-controllable birefringence and dichroism.

Crosslinker-free electrochemically-derived graphene oxide membranes are found to be extraordinarily stable in aqueous solutions and exhibit superior ionic sieving performance because of their unique chemical structure.

Properly controlling the rheological properties of nanoparticle inks is crucial to their printability. Here, it is reported that colloidal gels containing a dynamic network of graphene oxide (GO) sheets can display unusual rheological properties after high-rate shearing. When mixed with polyaniline nanofiber dispersions, the GO network not only facilitates the gelation process but also serves as an effective energy-transmission network to allow fast structural recovery after the gel is deformed by high-rate shearing. This extraordinary fast recovery phenomenon has made it possible to use the conventional air-brush spray technique to print the gel with high-throughput and high fidelity on nonplanar flexible surfaces. The as-printed micro-supercapacitors exhibit an areal capacitance 4-6 times higher than traditionally spray-printed ones. This work highlights the hidden potential of 2D materials as functional yet highly efficient rheological enhancers to facilitate industrial processing of nanomaterial-based devices., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A new class of superhydrophobic surface based on multiple hybrid coatings is proposed and prepared to improve mechanical and reproduction stability. It does not only show a large water contact angle (ca. 174.5°) but also a slight decrease (ca. 6.4%) of water contact angle after 100 mechanical abrasion cycles. Furthermore, the water contact angle changes slightly (relative standard deviation, 0.14%) for the three superhydrophobic surfaces prepared with the same procedure. The application of superhydrophobic multiple hybrid coatings in corrosion protection is further investigated by the Tafel polarization curves and electrochemical impedance spectroscopy. The superhydrophobic multiple hybrid coatings showed lower corrosion current (1.4 × 10 -11 A/cm 2 ), lower corrosion rate (ca. 1.6 × 10 -7 mm/year), and larger polarization resistance (7.9 × 10 4 MΩ cm 2 ) in 3.5 wt % NaCl aqueous solution compared to other superhydrophobic coatings reported in previous works. This work not only confirms the formation of robust superhydrophobic surface for real application in corrosion protection but also provides a new model of superhydrophobic surface based on multiple hybrid coatings with high mechanical, chemical, and reproduction stability for various applications.

To improve the success of medical devices, implants with strong surface bioactivity are urgently required. Coatings with a macroporous structure produced by micro-arc oxidation possess advantages, such as strong adhesion to substrate and excellent resistance to wear and corrosion. Mesoporous structures contain pores with sizes of 2-50 nm, which can endow the biomaterials with the ability to enhance osteogenesis and to be loaded with diverse drugs. Thus, in this study, we aimed to evaluate the effects of both macroporous and mesoporous structures using a hierarchical macro/mesoporous structure to modify the titanium implant surface. The behaviors of SaOS-2 human osteosarcoma cells on the macro/mesoporous structure, including initial adhesion, proliferation, alkaline phosphatase (ALP) activity, and collagen secretion, were investigated. Cells that attached on the macro/mesoporous surface showed the highest cell numbers and greatest spreading area after incubation for 1, 2, and 4 h compared with the polished smooth substrate and macroporous surface in the presence of fetal bovine serum (FBS). However, in the absence of FBS, cell adhesion on the polished substrate, macroporous structure, and macro/mesoporous structure did not differ significantly. Cell proliferation on the macroporous and macro/mesoporous surfaces increased compared with that on the smooth substrate surface. Furthermore, ALP activity and collagen secretion were enhanced on the macro/mesoporous structure. Our findings provided important insights into the cellular responses to macro/mesoporous structures in the field of implant surface modification. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1896-1902, 2018., (© 2018 Wiley Periodicals, Inc.)

Herein we report a new approach to fabricating nanoscrolls through the self-assembly of graphene oxide (GO) sheets in a dispersion. The assembly process for GO nanosheets was induced by the dropwise addition of an appropriate organic solvent such as N,N-dimethylformamide (DMF) into the aqueous dispersion. The results show that nanoscrolls were gradually formed from the GO sheets by rolling-up in a piece-by-piece manner with the increase of the DMF content. The transmission electron microscopic analysis indicates that for a typical case, the nanoscrolls have an average diameter of 242 ± 102 nm at the central part and the interlayer spacing between adjacent GO layers is 0.58 nm. The scrolls were estimated to have 207 turns and include on average 42 pieces of GO sheets per scroll. By this method, GO sheets with different sizes and oxidation degrees were proved to be able to form GO nanoscrolls in a similar way. Moreover, it is interesting that the diffraction efficiency of surface-relief-gratings photoinduced on the film of azo molecular glass was significantly enhanced by doping the GO nanoscrolls with a very low content (0.5 wt%); this suggests a possible new application for the GO scrolls in optical devices. This facile approach, which is also feasible by using other organic solvents such as ethanol, can be used to fabricate GO nanoscrolls for large scale applications in supercapacitors, sensors and other devices.

Micro/nanostructured TiO 2 /ZnO coating has been shown to possess multiple functions, including antibacterial activity and bioactivity. Osteoblast-like SaOS-2 cells were employed for evaluating the in vitro osteogenic capacity of this coating and positive results were obtained. However, traditional principles of osseointegration focus only on the osteogenic differentiation alone. The effects of immunomodulation on the osteogenic activity have been largely ignored. In this study, the inflammatory responses of macrophages on the micro/nanostructured TiO 2 /ZnO coating were investigated. The extract media of macrophage cell line RAW264.7 cultured on the TiO 2 /ZnO coating were collected as indirect co-culture conditioned media. The osteogenic activity of SaOS-2 cells in the conditioned media was investigated. Adhesion, ALP activity and extracellular mineralization of cells grown in the conditioned media extracted from the micro/nanostructured TiO 2 /ZnO coating were found to be enhanced, compared to those grown in the conditioned media extracted from the macroporous TiO 2 coating. The immune microenvironment produced by the micro/nanostructured TiO 2 /ZnO coating showed excellent capacity to promote osteogenesis, indicating that this coating could be a promising candidate for implant surface modification in orthopaedic and dental applications. Furthermore, this work could help us understand the interplay between the host immune system and the osteoimmunomodulatory properties of the biomaterials, and optimize the design for coating biomaterials.

A dual-layer TiO 2 surface with hierarchical macro and mesoporous structure was prepared by a combinational approach of micro-arc oxidation followed by evaporation-induced self-assembly of nano-crystallites. The mesoporous layer contains pores with an average size of <10nm and consists of anatase TiO 2 nanocrystallites. The dual-layer hierarchical macro/mesoporous structured TiO 2 surface improves the hydrophilicity and fibronectin adsorption ability in comparison with the sole macroporous or smooth TiO 2 surface. With the formation of an additional mesoporous layer on macroporous TiO 2 surface, the attached number of human osteogenic sarcoma cells (SaOS-2) increases in the initial incubation of 4h but it does not show significant difference after 24h compared to that attached on the macroporous or smooth surfaces. Whereas, it was noticed that SaOS-2 cells have larger spread area and more stress fibers on the macro/mesoporous structured surface than those on the other surfaces. To understand the intracellular mechanism of the initial cell adhesion on the macro/mesoporous surface, the Rho/ROCK pathway was investigated to reveal the topography-induced biological functions by introducing the ROCK inhibitor Y-27632 during cell culture. In the presence of Y-27632, cells on the macroporous surface and macro/mesoporous surface both show stellate appearance, with poor assembly stress fibers and long cell membrane protrusions. Cells on the smooth surface have larger spread areas compared to the former two surfaces. And the attached cells significantly reduced but there are no differences among the three surfaces. It reveals that the ROCK inhibitor invalidates the promotion of initial cell adhesion on the macro/mesoporous structure. This study may shed light on the mechanism behind the enhancement effect of macro/mesoporous structure for initial cell adhesion., (Copyright © 2017. Published by Elsevier B.V.)

Mechanically tough large-area hierarchical porous graphene films are fabricated by blade-casting of graphene oxide hydrogel and postcasting reduction. The as-prepared graphene films, which consist of well-exfoliated graphene nanosheets, possess interpenetrating 3D hierarchical porous structures, high strength and modulus, large specific area, and high electrical conductivity. Flexible film supercapacitors fabricated with the graphene electrodes show superior areal capacitance, good rate performance, and excellent mechanical stability., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Photo-cross-linkable multilayer films composed of sulfonated reduced graphene oxide (SRGO) and polystyrene-based diazonium salt (PSDAS) were fabricated by electrostatic layer-by-layer (LbL) self-assembly. Polystyrene with narrow molecular weight distribution was synthesized by atom transfer radical polymerization (ATRP), and cationic PSDAS was prepared through nitration, reduction, and diazotization reactions. Negatively charged SRGO nanosheets were prepared through prereduced by NaBH4, modified by diazonium salt of sulfanilic acid, and then further reduced by hydrazine. The multilayer films were obtained by alternately dipping substrates in the PSDAS solution and SRGO dispersion in acidic conditions. The cross-linking between the components occurred during the multilayer formation process and was further achieved by the UV light irradiation after the film preparation. The assembling process and surface morphology of LbL multilayer films were monitored by UV-vis spectroscopy, atomic force microscopy (AFM), and scanning electron microscopy (SEM). The cross-linking between SRGO and PSDAS was verified by attenuated total reflectance FTIR (ATR-FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and contact angle measurement. The graphene nanosheets were found to be homogeneously distributed in the cross-linked network of the films. The large accessible surface area of graphene nanosheets and the cross-linking structure afforded the LbL films with high specific capacitance and excellent cyclic stability when used as supercapacitor electrodes. At a sweeping rate of 10 mV/s, the film with nine bilayers exhibited a specific capacitance of 150.4 F/g with ideal rectangular cyclic voltammogram. Large capacitance retention of 97% was observed after 10 000 charge-discharge cycles under the scanning rate of 1000 mV/s. This new approach for preparing graphene-containing multilayer films can be used to develop supercapacitor electrodes and other functional devices.