Fast Pathway Research Articles

Constructing Fast Transmembrane Pathways in a Layered Double Hydroxide Nanosheets/Nanoparticles Composite Film for an Inorganic Anion-Exchange Membrane

Anion-exchange membranes (AEMs) with high conductivity are crucial for realizing next-generation energy storage and conversion systems in an alkaline environment, promising a huge advantage in cost reduction without using precious platinum group metal catalysts. Layered double hydroxide (LDH) nanosheets, exhibiting a remarkably high hydroxide ion (OH-) conductivity approaching 10-1 S cm-1 along the in-plane direction, may be regarded as an ideal candidate material for the fabrication of inorganic solid AEMs. However, two-dimensional anisotropy results in a substantially low conductivity of 10-6 S cm-1 along the cross-plane direction, which poses a hurdle to achieve fast ion conduction across the membrane comprising restacked nanosheets. In the present work, a composite membrane was prepared based on mixing/assembling micron-sized LDH nanosheets with nanosized LDH platelets (nanoparticles) via a facile vacuum filtration process. The hybridization with nanoparticles could alter the orientation of LDH nanosheets and reduce the restacking order, forming diversified fast ion-conducting pathways and networks in the composite membrane. As a result, the transmembrane conductivity significantly improved up to 1000-fold higher than that composed of restacked nanosheets only, achieving a high conductivity of 10-2 to 10-1 S cm-1 in both in-plane and cross-plane directions.

Supramolecular interactions enable pseudo-nanophase separation for constructing an ion-transport highway

•A pseudo-nanophase-separation strategy is proposed for constructing an ion-transport highway •“Side chains” are “grafted” onto polymer backbones via supramolecular interactions •Chemical stability issues caused by covalent modifications are circumvented •Supramolecular interactions and underlying mechanisms are clearly elucidated A well-defined hydrophilic/hydrophobic nanophase-separated structure is widely applied for the construction of fast ion-transport pathways in polymeric membranes for energy-related applications such as electrochemical reactors, fuel cells, and redox flow batteries (RFBs). Conventional nanophase separation is induced by covalently grafted side chains, which however complicate membrane preparation and potentially reduce the chemical stability of membranes. In this work, we report a pseudo-nanophase-separation strategy enabled by supramolecular interactions to construct fast and selective ion-transport channels in polymeric membranes. The “side chains” are “grafted” onto the polymer backbone via supramolecular interactions instead of covalent bonds, simplifying the membrane preparation process and simultaneously protecting the polymer backbone from chemical degradation, which is a critical problem usually found in membranes with molecular modifications. The pseudo-nanophase separation enables high-performance membranes for aqueous acidic RFBs, showing high efficiency and good cycling stability, which suggests its potential to design highly conductive and chemically stable membranes for various energy-related devices. A well-defined hydrophilic/hydrophobic nanophase-separated structure is widely applied for the construction of fast ion-transport pathways in polymeric membranes for energy-related applications such as electrochemical reactors, fuel cells, and redox flow batteries (RFBs). Conventional nanophase separation is induced by covalently grafted side chains, which however complicate membrane preparation and potentially reduce the chemical stability of membranes. In this work, we report a pseudo-nanophase-separation strategy enabled by supramolecular interactions to construct fast and selective ion-transport channels in polymeric membranes. The “side chains” are “grafted” onto the polymer backbone via supramolecular interactions instead of covalent bonds, simplifying the membrane preparation process and simultaneously protecting the polymer backbone from chemical degradation, which is a critical problem usually found in membranes with molecular modifications. The pseudo-nanophase separation enables high-performance membranes for aqueous acidic RFBs, showing high efficiency and good cycling stability, which suggests its potential to design highly conductive and chemically stable membranes for various energy-related devices.

Outcrop scale mixing enhanced by permeability variations: the role of stationary and travelling waves of high saturation indices

AbstractTo study the ore mineralization at the outcrop scale we merge an advection–diffusion simulation with the geochemical software iphreeqc to model the mixing of two realistic fluids. We simulate the infiltration of a metal-rich fluid into a rock that is saturated with pore fluid. We test the feedback effects with a number of scenarios based on an outcrop-scale 5 × 5 m model consisting of two high-permeable vertical faults within a low-permeable host rock that lead into a permeable layer. The hot metal-rich fluid enters the model through the faults from below. We solve the advection–diffusion equation for 12 chemical species and temperature, and use iphreeqc to determine the resulting properties of local fluid domains as well as related saturation indices for minerals. The faults in the model act as pathways for the metal-rich fluid, with the infiltrating fluid displacing the pore fluid. Mixing in the model takes place as a function of advection along permeable faults coupled with diffusion of chemical species at the interface between two fluids, while heat diffusion is fast enough (103 times faster) to equilibrate temperature. Simulations show a high saturation index of mixing-derived minerals such as barite at the interface between the two fluids as a result of fluid mixing. Fast fluid pathways (i.e. faults) show travelling waves of high saturation indices of barite, while low-permeability zones such as fault walls and areas below less permeable layers experience stationary waves of high saturation indices. Our results show that, depending on the dominant transport process (advection or diffusion), mineralization will localize next to permeability contrasts in zones where local diffusion dominates.

CTpathway: a CrossTalk-based pathway enrichment analysis method for cancer research

BackgroundPathway enrichment analysis (PEA) is a common method for exploring functions of hundreds of genes and identifying disease-risk pathways. Moreover, different pathways exert their functions through crosstalk. However, existing PEA methods do not sufficiently integrate essential pathway features, including pathway crosstalk, molecular interactions, and network topologies, resulting in many risk pathways that remain uninvestigated.MethodsTo overcome these limitations, we develop a new crosstalk-based PEA method, CTpathway, based on a global pathway crosstalk map (GPCM) with >440,000 edges by combing pathways from eight resources, transcription factor-gene regulations, and large-scale protein-protein interactions. Integrating gene differential expression and crosstalk effects in GPCM, we assign a risk score to genes in the GPCM and identify risk pathways enriched with the risk genes.ResultsAnalysis of >8300 expression profiles covering ten cancer tissues and blood samples indicates that CTpathway outperforms the current state-of-the-art methods in identifying risk pathways with higher accuracy, reproducibility, and speed. CTpathway recapitulates known risk pathways and exclusively identifies several previously unreported critical pathways for individual cancer types. CTpathway also outperforms other methods in identifying risk pathways across all cancer stages, including early-stage cancer with a small number of differentially expressed genes. Moreover, the robust design of CTpathway enables researchers to analyze both bulk and single-cell RNA-seq profiles to predict both cancer tissue and cell type-specific risk pathways with higher accuracy.ConclusionsCollectively, CTpathway is a fast, accurate, and stable pathway enrichment analysis method for cancer research that can be used to identify cancer risk pathways. The CTpathway interactive web server can be accessed here http://www.jianglab.cn/CTpathway/. The stand-alone program can be accessed here https://github.com/Bioccjw/CTpathway.

Specialist nurse training in ultrasonography for the diagnosis of giant cell arteritis.

Dear Editor, Ultrasonography is a diagnostic modality that has been tested to OMERACT standards for the diagnosis of GCA [1]. It is a bedside tool with ubiquitously available technology. It can lead to earlier diagnosis or exclusion of GCA, potentially improving outcomes and minimizing glucocorticoid toxicity. Ultrasonography is more cost effective than temporal artery biopsy (TAB) with fewer resources needed to run the ultrasound service [2]. These attributes led it to be the recommended first line investigation for the diagnosis of GCA [3]. However, it is restricted by the availability of trained sonographers. Our centre has a validated GCA fast track pathway [4]. But, it is reliant on the skills of one expert sonographer (C.B.M.), which is a clinical risk. To mitigate this risk a vasculitis specialist nurse (G.D.) has been trained in ultrasonography for the diagnosis of GCA. There is a precedent for a nurse-led temporal artery biopsy service [5]. Temporal arterial biopsy has many limitations including the sampling of a single artery. Ultrasonography has the benefit of examining arteries more extensively, looking for cranial and extra-cranial involvement as recommended by the British Society for Rheumatology [6].

Electrophysiological characteristics and catheter ablation of atypical fast-slow atrioventricular nodal reentrant tachycardia using an inferolateral left atrial slow pathway

Abstract Background Understandings of subtypes of atypical atrioventricular nodal reentrant tachycardia (AVNRT) using variants of slow pathway (SP) are still growing. Inferolateral (inf-lat-) left atrial (LA) SP is a rare variant extending into an inf-lat-LA along the mitral annulus (MA). Purpose To characterize an unknown subtype of atypical fast-slow (F/S-) AVNRT using an inf-lat-LA-SP as a retrograde limb (inf-lat-LA-F/S-AVNRT). Methods This Japanese multicenter retrospective study enrolled 4 patients of inf-lat-LA-F/S-AVNRT that was characterized by the earliest site of atrial activation during tachycardia (EAA) between 3 and 6 o'clock along the MA. The diagnosis was made by an exclusion of AV reentrant tachycardia (AVRT) and atrial tachycardia (AT) according to the standard criteria and was confirmed by successful elimination of tachycardia and the inf-lat-LA-SP. Results Surface ECG during tachycardia revealed long RP appearance except one who had short RP due to a short conduction time across the inf-lat-LA-SP. During tachycardia, far-field LA activation preceding near-field activation of coronary sinus (CS) musculature was visible in the CS recording in 2. Retrograde conduction via the inf-lat-LA-SP with a decremental delay was consistently reproducible with ventricular stimulation in 2, 1 of whom had double atrial response, while it was always masked by the presence of a retrograde conduction via the fast pathway in 1 and a retrograde block at the lower common pathway in 1. An injection of a small dose of ATP transiently interrupted a retrograde conduction over the inf-lat-LA-SP, suggesting its ATP-sensitivity. Exclusion of AVRT was made by no resetting of tachycardia with left ventricular extrastimulus in 2 and VA dissociation during overdrive pacing of tachycardia in remaining 2. Exclusion of AT was made by V-A-V response after ventricular entrainment in 1 and termination without atrial capture by ventricular pacing in 2. Ablation of the right-sided SP was unsuccessful to eliminate the tachycardia, but ablation at or near the EAA by transseptal approach was successful to cure the tachycardia, associated with an elimination of a retrograde conduction over the inf-lat-LA-SP following a development of an accelerated junction rhythm in all. Low-frequency potentials preceding local atrial activation, consistent with a retrograde activation via the inf-lat-LA-SP were detected along the MA medial to the EAA in 1. Conclusions Differential diagnosis of tachycardia with the EAA in the inf-lat-LA and especially long RP appearance should include inf-lat-LA-F/S-AVNRT. Presumed arrhythmogenic substrate of the inf-lat-LA-SP seemed to be consistent with the remnant of embryogenic AV ring tissue in the electropharmacological and locational characteristics. Successful elimination of this AVNRT can be obtained by ablation of the inf-lat-LA-SP, but not of the right-sided SP. Funding Acknowledgement Type of funding sources: None.

Constructing angustifolia-like MoS2 on Ag nanowires as anode with enhanced diffusion kinetics for Li-ion batteries

The unfavorable rate capacities and cycling property are insurmountable problems for application of pure MoS2 anode in Li-ion batteries. In this regard, a brief methodology used in the synthesis of AgNWs@MoS2 is discussed. Emphasis is placed on the construction of a nanocomposite anode by which the cycling behavior and rate capability of MoS2 can be improved. As the 1D skeletons of Ag nanowires constitute fast conductive pathways and prevent volume expansion of pure MoS2 as charge/discharge process, enhancing the Li+ diffusion coefficient in electrode. The experimental results reveal interesting examples of AgNWs@MoS2 anode of admirable rate property and promising long-cycling appearance (310 mAh g−1 at 1 A g−1 after 1000 cycles). The scope of this research lies in providing a type of excellent anode material in Li-ion batteries.

Successful Typical AVNRT Ablation

AVNRT is the most common regular arrhythmia in humans, and therefore the most commonly encountered during ablation attempts for regular tachycardias. Case Summary: We present a 41-year-old female patient with chest palpitations in the last 10 years, but prior to hospitalization felt heavy sensation on her chest and hospitalized due to heavy chest palpitations and documented SVT. She had no history of hypertension, diabetes mellitus, coronary heart conditions, or stroke. Physical examination showed fair general condition with GCS E4V5M6, blood pressure 130/80, pulse rate 96x / minute, breath rate 18 x / minute and saturation of 99%. Physical examinations are within normal limits. Discussion: Catheter ablation for AVNRT is the current treatment of choice in symptomatic patients. It reduces arrhythmia-related hospitalizations and costs, and substantially improves quality of life. Catheter ablation approaches aimed at the fast pathway have been abandoned; slow pathway ablation, using a combined anatomical and mapping approach, is now the method of choice. This approach offers a success rate of 95 %, has a recurrence rate of approximately 1.3 – 4.0 %, and has been associated with a low risk of atrioventricular (AV) block.

Construction of hierarchical Co, Fe Co-doped MoS2/polypyrrole heterostructure as an efficient bifunctional catalyst for enzyme-like and nitrophenol catalysis

Constructing tubular MoS2-based hybrid composites with heterostructure is effective for enhancing the catalytic performance of hybrid nanozymes. Herein, we present a multi-step “molecule/ion-exchange” strategy and post-sulfidation treatment to fabricate hierarchical microtubes by growing a Co, Fe co-doped MoS2 nanosheets(NSs) on polypyrrole(PPy) microtubes. The hierarchical tubular structure provides fast transport pathways for electrons, and the voids effectively facilitate mass diffusion. Owing to their synergistic effect between their unique tubular PPy structure and hierarchical Co, Fe co-doped MoS2 NSs, the Co, Fe-MoS2 @PPy microtubes exhibited extraordinary activity and stability in the reduction of 4-nitrophenol as well as peroxidase-like catalysis. Moreover, this dual transition metal doped approach would give novel inspiration for designing and synthesizing other tubular MoS2-based composites with tailored compositions, which could be used as a promising candidate for other energy-related applications.

Spatiotemporal Feature Enhancement Aids the Driving Intention Inference of Intelligent Vehicles.

In order that fully self-driving vehicles can be realized, it is believed that systems where the driver shares control and authority with the intelligent vehicle offer the most effective solution. An understanding of driving intention is the key to building a collaborative autonomous driving system. In this study, the proposed method incorporates the spatiotemporal features of driver behavior and forward-facing traffic scenes through a feature extraction module; the joint representation was input into an inference module for obtaining driver intentions. The feature extraction module was a two-stream structure that was designed based on a deep three-dimensional convolutional neural network. To accommodate the differences in video data inside and outside the cab, the two-stream network consists of a slow pathway that processes the driver behavior data with low frame rates, along with a fast pathway that processes traffic scene data with high frame rates. Then, a gated recurrent unit, based on a recurrent neural network, and a fully connected layer constitute an intent inference module to estimate the driver’s lane-change and turning intentions. A public dataset, Brain4Cars, was used to validate the proposed method. The results showed that compared with modeling using the data related to driver behaviors, the ability of intention inference is significantly improved after integrating traffic scene information. The overall accuracy of the intention inference of five intents was 84.92% at a time of 1 s prior to the maneuver, indicating that making full use of traffic scene information was an effective way to improve inference performance.

Electrochemical Properties of LiFePO4 Cathodes: The Effect of Carbon Additives

The influence of different conductive additives (carbon nanofibers (CNFs), carbon nanoplatelets, and pyrolytic carbon from sucrose (Sucr) or polyvinylidene fluoride) on the morphology, electron conductivity, and electrochemical performance of LiFePO4-based cathodes was investigated to develop the most efficient strategy for the fabrication of high-rate cathodes. Pyrolytic carbon effectively prevents the growth of LiFePO4 grains and provides contact between them, CNFs provide fast long-range conductive pathways, while carbon nanoplatelets can be embedded in carbon coatings as high-conductive “points” which enhance the rate capability and decrease the capacity fading of LFP. The LiFePO4/CSucr/CNF showed better performance than the other cathodes due to the synergy of the high-conductive CNF network (the electronic conductivity was 1.3 × 10−2 S/cm) and the shorter Li+ ion path (the lithium-ion diffusion coefficient was 2.1 × 10−11 cm2/s). It is shown that the formation of composites based on LFP and carbon nanomaterials via mortar grinding is a more promising strategy for electrode material manufacturing than ball milling.

Tailoring electronic-ionic local environment for solid-state Li-O2 battery by engineering crystal structure.

Solid-state Li-O2 batteries (SSLOBs) have attracted considerable attention because of their high energy density and superior safety. However, their sluggish kinetics have severely impeded their practical application. Despite efforts to design highly efficient catalysts, efficient oxygen reaction evolution at gas-solid interfaces and fast transport pathways in solid-state electrodes remain challenging. Here, we develop a dual electronic-ionic microenvironment to substantially enhance oxygen electrolysis in solid-state batteries. By designing a lithium-decorative catalyst with an engineering crystal structure, the coordinatively unsaturated sites and high concentration of defects alleviate the limitations of electronic-ionic transport in solid interfaces and create a balanced gas-solid microenvironment for solid-state oxygen electrolysis. This strategy facilitates oxygen reduction reaction, mediates the transport of reaction species, and promotes the decomposition of the discharge products, contributing to a high specific capacity with a stable cycling life. Our work provides previously unknown insight into structure-property relationships in solid-state electrolysis for SSLOBs.

Heterogeneous WO2/WS2 microspheres synergized with reduced graphene oxides with high rate capacity for superior sodium-ion capacitors

• Heterogeneous WO 2 /WS 2 microspheres wrapped by reduced graphene oxide are prepared. • WO 2 /WS 2 nanosheets shorten Na + diffusion and WO 2 guarantee high electron conductivity. • RGO provide structure protecting layer and alleviate the volume change of WO 2 /WS 2. • WO 2 /WS 2 -rGO electrode exhibits large capacity, high rate and long cycle life. • A 4.0 V sodium-ion capacitor achieves 140 Wh kg −1 at 200 W kg −1. High rate capacity and long-term cycling stability are the pursuing characteristic of a promising anode for sodium-ion capacitors (SICs). However, the sluggish reaction kinetics and aggregation of volume during sodiation/desodiation process are the main obstacles. In this work, we developed a 3D porous WO 2 /WS 2 -rGO network while urchin-like microspheres self-assembled by WO 2 /WS 2 heterogeneous nanosheets and wrapped by rGO network, demonstrating superior rate properties and cycling stability as the anode of sodium-ion batteries (SIBs). The ultrathin WO 2 /WS 2 nanosheets contribute to shorten the Na + diffusion length, while metallic WO 2 guaranteeing high electric conductivity of nanosheet units and rGO network help to construct the fast dual electron transfer pathways during sodiation/desodiation process. Also, rGO network can provide a stable structure protecting layer and alleviate the volume change of WO 2 /WS 2 . Benefiting from these merits, WO 2 /WS 2 -rGO electrode reveals a dominanting capacitive-controlled process especially at the higher scan rates and achieves 100 mAh g −1 at an ultrahigh current density of 25.6 A g −1 as well as maintains 90% capacity retention over 1000 cycles at 1 A g −1 . The SICs comprising of WO 2 /WS 2 -rGO anode and 3D phosphorus-doped carbon (P C) cathode demonstrate outstanding energy density of 140 Wh kg −1 at 200 W kg −1 along with a reasonable stable cycling of 79% capacity retention over 6000 cycles at 5 A g −1 within the voltage of 0.0–4.0 V. The proposed strategy integrates hierarchical heterogeneous structure and effective dual electron transfer network can be applied to develop promising electrode materials for high performance energy storage systems.

New insights into the mechanisms of fast and slow conduction in the atrioventricular node

Cardiac pathologists and electrophysiologists have studied the atrioventricular (AV) node since 1906, when Tawara 1 Tawara S. Das Reitzleitungssystem des Saugetierherzens: Eine anatomisch-histologische Studie uber das Atrioventrikularbundel und die Purkinjeschen Faden. Gustav Fischer, Jena, Germany1906: 135-136 Google Scholar described its inferior extensions in the human heart. One century later, this important cardiac structure still carries the reputation of a profound enigma, invoked as the riddle of Sphinx, by means of its electrophysiological properties during both normal conduction and reentrant tachycardia. 2 Katritsis D.G. The human atrioventricular node: oedipus and the riddle of the Sphinx. Arrhythm Electrophysiol Rev. 2020; 9: 52-53 Crossref PubMed Scopus (0) Google Scholar In recent years, considerable evidence has accrued pertaining to its anatomic structure, 3 Inoue S. Becker A.E. Posterior extensions of the human compact atrioventricular node: a neglected anatomic feature of potential clinical significance. Circulation. 1998; 97: 188-193 Crossref PubMed Scopus (271) Google Scholar , 4 Hikspoors J. Macias Y. Tretter J.T. et al. Miniseries 1–part I: the development of the atrioventricular conduction axis. Europace. 2022; 24: 432-442 Crossref PubMed Scopus (1) Google Scholar , 5 Macias Y. de Almeida M.C. Tretter J.T. et al. Miniseries 1–part II: the compara-tive anatomy of the atrioventricular conduction axis. Europace. 2022; 24: 443-454 Crossref PubMed Scopus (3) Google Scholar , 6 Anderson R.H. Sanchez-Quintana D. Mori S. Cabrera J.A. Back Sternick E. Re-evaluation of the structure of the atrioventricular node and its connections with the atrium. Europace. 2020; 22: 821-830 Crossref PubMed Scopus (32) Google Scholar along with the electrophysiological properties, which have allowed identification of the so-called fast and slow pathways involved in atrioventricular nodal reentrant tachycardia (AVNRT). 7 Katritsis D.G. Josephson M.E. Classification, electrophysiological features and therapy of atrioventricular nodal reentrant tachycardia. Arrhythm Electrophysiol Rev. 2016; 5: 130-135 Crossref PubMed Scopus (29) Google Scholar , 8 Katritsis D.G. A unified theory for the circuit of atrioventricular nodal re-entrant tachycardia. Europace. 2020; 22: 1763-1767 Crossref PubMed Scopus (7) Google Scholar , 9 Katritsis D.G. Calkins H. Anderson R.H. The specialized atrioventricular ring tissues participate in the circuit of atrioventricular nodal reentrant tachycardia. J Am Heart Assoc. 2021; 10e022811 Crossref Scopus (0) Google Scholar But still the nature of these patterns of conduction in the context of sinus rhythm, as opposed to those observed during tachycardia, remains obscure. In the great Sophoclean tragedy, in light of its insurmountable difficulty, the denouement of the riddle of Sphinx by mortal Oedipus was initially perceived by the Athenians as a form of hubris against the gods by a human. 10 Sophocles. Oedipus Tyrannus. 429 BC. Google Scholar We believe that the accumulation of recent anatomic and electrophysiological evidence now enables us to provide the rationale for solving the nodal riddle without committing scientific hubris.

Si segregation and relevant effect on the corrosion propagation in F/M steel exposed to liquid lead-bismuth eutectic

ABSTRACT Clarification of the relationship between oxygen diffusion and microstructural evolution in liquid lead-bismuth eutectic (LBE) is of great importance for understanding and consequently tailoring the oxidation process. In the present study, a Si-modified ferritic martensitic steel was exposed to oxygen-saturated LBE at 500°C at various times and the interface between the internal oxidation zone and matrix was investigated. Microstructural characterisation reveals that grain boundaries and martensitic lath boundaries provide a fast pathway for oxygen diffusion, resulting in the high amount of oxidation products, as well as cracks. The internal stress caused by the formation of oxidation products along grain boundary results in the proliferation of dislocations, which subsequently play as the new diffusion channel for oxygen. The chemical analysis demonstrates that Si preferably concentrates along the dislocations in a form of Si-rich oxide, suggesting the oxidation of Si is prior to the Cr-rich oxide.

Microwave-assisted pyrolysis spent bleaching clay for aromatic bio-oil production: Exploration of heating pathway based on microwave response characteristics of feedstock

Spent bleaching clay (SBC) is a waste generated from the refining process of edible oils. SBC contains some residual oils, with excellent potential to produce aromatic bio-oil. For the first time, microwave-assisted pyrolysis was used to treat SBC, which has unique microwave response characteristics. The products of microwave heating and electric heating were investigated, under three conditions: no catalyst, in-situ catalysis, and ex-situ catalysis. Microwave heating saved 50% of the reaction time and up to 53% of the energy consumption, compared to electric heating. Microwave heating facilitated the formation of aromatic hydrocarbons by promoting hydrogen transfer and cyclization reactions. In comparison with electric heating, the aromatic hydrocarbons relative content was increased by 15.46% under no catalyst. In addition, the optimal pyrolysis temperature, catalytic temperature, feedstock to catalyst mass ratio (F/C) and nitrogen flow rate based on microwave heating pathway were 500 °C, 500 °C, 10/1, and 50 mL/min, respectively. Under these conditions, the relative content of aromatic hydrocarbons was 87.89%. Microwave-assisted catalytic pyrolysis is a fast and energy efficient pathway to produce aromatic bio-oil from SBC, which can provide a theoretical basis for resource utilization of SBC.

Rapid increase in transferrin receptor recycling promotes adhesion during T cell activation

BackgroundT cell activation leads to increased expression of the receptor for the iron transporter transferrin (TfR) to provide iron required for the cell differentiation and clonal expansion that takes place during the days after encounter with a cognate antigen. However, T cells mobilise TfR to their surface within minutes after activation, although the reason and mechanism driving this process remain unclear.ResultsHere we show that T cells transiently increase endocytic uptake and recycling of TfR upon activation, thereby boosting their capacity to import iron. We demonstrate that increased TfR recycling is powered by a fast endocytic sorting pathway relying on the membrane proteins flotillins, Rab5- and Rab11a-positive endosomes. Our data further reveal that iron import is required for a non-canonical signalling pathway involving the kinases Zap70 and PAK, which controls adhesion of the integrin LFA-1 and eventually leads to conjugation with antigen-presenting cells.ConclusionsAltogether, our data suggest that T cells boost their iron importing capacity immediately upon activation to promote adhesion to antigen-presenting cells.

The dual role of interlayer crosslinks leads to an abnormal behavior of interlayer thermal resistance in multilayer graphene

Understanding and controlling the interlayer thermal resistance (ITR) are crucial to the cross-plane thermal transport in multilayer graphene (MLG). Using non-equilibrium molecular dynamics simulations, we show that the ITR of MLG can be effectively tuned by in-plane defects, sp2 and sp3 C–C bond crosslinks. Specifically, with the increase of the in-plane defect density, the ITR initially increases sharply and then almost saturates; while with the increase of the crosslink density, the ITR initially also increases sharply, then peaks and subsequently decreases rapidly to a level that can be even lower than that of pristine MLG. The underlying mechanism for this unexpected variation of ITR with crosslink density is explored through the analyses of the phonon density of states (DOS) and spectral transmission function. It was found that the crosslinks play a dual role: the crosslink-generated in-plane defect enhances phonon scattering and leads to an increase in the ITR, while the interlayer bonding gives rise to a fast phonon transmission pathway and decreases the ITR. An effective medium approximation (EMA) model was proposed to describe the dual role of the crosslinks. This work provides new insight into the thermal transport behavior of crosslinks, which is useful for modulating the cross-plane thermal transport of MLG for the thermal management of MLG-based nanodevices.

Improvements in Li deposition and stripping induced by Cu (111) nanotwinned columnar grains

How to depress the dendrite growth, promote the coulombic efficiency, and improve the cycling stability of Li plating/stripping on Cu foils is a strict challenge in the lithium metal-free batteries (LMfBs). Here, the Cu substrates with the (111)-preferred orientation and the (111)-nanotwinned lamella grains are compared for the performance of Li deposition/stripping in 1 M lithium hexafluorophosphate/ethylene carbonate-dimethyl carbonate (LiPF6/EC-DMC with EC:DMC=50:50 vol.%). The presence of twin boundaries in the Cu foil does decrease the total interfacial energy of the copper surface, favoring the formation of the LiF-amorphous matrix solid electrolyte interphase (SEI) to provide fast Li-ion pathways and inducing the growth of UPD (underpotential deposition) Li. As a result, the (111)-nanotwinned copper foil significantly reduces the nucleation overpotential of Li plating, uniforms the lithium deposit, improves the coulombic efficiency, and ameliorates the cycling stability of Li plating/stripping. The microstructures of Cu foils with the (111)-preferred orientation and the (111)-nanotwinned lamella grains have been confirmed by the X-ray diffraction (XRD), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM).

Role of Temporal artery biopsy in a sequential Giant Cell Arteritis fast-track pathway: a 5-year prospective study.

Increasing number of centres are establishing sequential fast track pathways (FTP) for management of giant cell arteritis (GCA), with temporal artery ultrasound (US) replacing temporal artery biopsy (TAB) as the first investigational method. Biopsy is performed as second investigation, when US is negative/inconclusive. This study investigates the role of TAB in a sequential GCA-FTP and its utility in those with negative/inconclusive US. Prospective study of patients referred for TAB as part of Coventry sequential GCA-FTP May 2014-June 2019. Analysis included sensitivity and specificity of TAB, impact of arterial specimen length and duration of treatment with corticosteroids on sensitivity of TAB and the clinical predictors for a positive biopsy. A total of 1149 patients with suspected GCA were referred to this GCA-FTP, with 109 (9.5%) referred for TAB. Overall sensitivity of TAB was 47% (specificity: 100%) and in patients with negative/inconclusive US sensitivity was 39% (specificity:100%). Post-fixation arterial specimen length <15 mm showed lower sensitivity (14%), which increased to 52% when specimen length was ≥15 mm. Sensitivity of TAB was highest in first 7 (60%) to 10 days (59%) from starting corticosteroids. Predictors of positive biopsy using univariate logistic regression analysis were jaw claudication (OR = 5.40; p = 0.0057), elevated erythrocyte sedimentation rate (OR = 5.50; p = 0.013) and elevated C-reactive protein (OR = 23.7; p = 0.0043). This is the first study to look at the role of TAB in a sequential GCA-FTP. Biopsy plays an important role in GCA-FTP, when US is negative/inconclusive. Sensitivity of TAB improved when specimen length was ≥15 mm and performed within 10 days of commencing corticosteroids.