Analysis of risk factors for postoperative deep vein thrombosis after craniotomy and nomogram model construction

BACKGROUND Deep vein thrombosis(DVT)of the lower extremity is one of the most common postoperative complications,especially after craniocerebral surgery.DVT may lead to pulmonary embolism,which has a devastating impact on patient prognosis.This study aimed to investigate the incidence and risk factors of DVT in the lower limbs following craniocerebral surgery.AIM To identify independent risk factors for the development of postoperative DVT and to develop an effective risk prediction model.METHODS The demographic and clinical data of 283 patients who underwent craniocerebral surgery between December 2021 and December 2022 were retrospectively analyzed.The independent risk factors for lower extremity DVT were identified by univariate and multivariate analyses.A nomogram was created to predict the likelihood of lower extremity DVT in patients who had undergone craniocerebral surgery.The efficacy of the prediction model was determined by receiver operating characteristic curve using the probability of lower extremity DVT for each sample.RESULTS Among all patients included in the analysis,47.7%developed lower extremity DVT following craniocerebral surgery.The risk of postoperative DVT was higher in those with a longer operative time,and patients with intraoperative intermittent pneumatic compression were less likely to develop postoperative DVT.CONCLUSION The incidence of lower extremity DVT following craniocerebral surgery is significant,highlighting the importance of identifying independent risk factors.Interventions such as the use of intermittent pneumatic compression during surgery may prevent the formation of postoperative DVT.

Computational model investigating the effect of magnetic field on neural–astrocyte microcircuit

Extremely low-frequency magnetic field is widely used as a noninvasive stimulation method in clinical practice and basic research. Electrical field induced from magnetic pulse can decrease or increase neuronal electrical activity. However, the cellular mechanism underlying the effects of magnetic field is not clear from experimental data. Recent studies have demonstrated that "non-neuronal" cells, especially astrocytes, may be the potential effector for transcranial magnetic stimulation(TMS). In the present study, we implemented a neural–astrocyte microcircuit computational model based on hippocampal architecture to investigate the biological effects of different magnetic field frequencies on cells. The purpose of the present study is to elucidate the main influencing factors of MS to allow a better understanding of its mechanisms.Our model reproduced the basic characteristics of the neuron and astrocyte response to different magnetic stimulation. The results predict that interneurons with lower firing thresholds were more active in magnetic fields by contrast to pyramidal neurons. And the synaptic coupling strength between the connected neurons may be one of the critical factor to affect the effect of magnetic field on cells. In addition, the simulations show that astrocytes can decrease or increase slow inward currents(SICs) to finely tune neuronal excitation, which suggests their key role in excitatory–inhibitory balance. The interaction between neurons and astrocytes may represent a novel target for effective therapeutic strategies involving magnetic stimulation.

Layered oxide cathodes for sodium-ion batteries: From air stability, interface chemistry to phase transition

Sodium-ion batteries(SIBs)are considered as a low-cost complementary or alternative system to prestigious lithium-ion batteries(LIBs)because of their similar working principle to LIBs,cost-effectiveness,and sustainable availability of sodium resources,especially in large-scale energy storage systems(EESs).Among various cathode candidates for SIBs,Na-based layered transition metal oxides have received extensive attention for their relatively large specific capacity,high operating potential,facile synthesis,and environmental benignity.However,there are a series of fatal issues in terms of poor air stability,unstable cathode/electrolyte interphase,and irreversible phase transition that lead to unsatisfactory battery performance from the perspective of preparation to application,outside to inside of layered oxide cathodes,which severely limit their practical application.This work is meant to review these critical problems associated with layered oxide cathodes to understand their fundamental roots and degradation mechanisms,and to provide a comprehensive summary of mainstream modification strategies including chemical substitution,surface modification,structure modulation,and so forth,concentrating on how to improve air stability,reduce interfacial side reaction,and suppress phase transition for realizing high structural reversibility,fast Na+kinetics,and superior comprehensive electrochemical performance.The advantages and disadvantages of different strategies are discussed,and insights into future challenges and opportunities for layered oxide cathodes are also presented.

Bifunctional sulfonated covalent polymers as the modulator for oriented and highly reversible zinc plating

The vast superiority in resource sustainability and volumetric energy density enables metallic zinc(Zn)to construct costeffective and environment-benign battery systems for the energy storage.However,the problems of Zn dendrites and poor Coulombic efficiency(CE)during cell’s whole life cycle stump its advancement as a rechargeable battery choice.The solution is to modulate the Zn^(2+) desolvation prior to electro-reduction and subsequent deposition.Herein,a transferred protection tactic via a bifunctional sulfonated covalent polymer interlayer is proposed to regulate the Zn2+desolvation,which affects the formation of solid-electrolyte interphase,and guides its plating along with preferable(002)crystal plane.Thus,the high initial CE of 96.3%and the long-term average CE of 99.8%for 310 cycles are achieved in Zn||Cu cells and 570-h circulation is also realized at 2 mA cm^(-2)/10 mAh cm^(-2)in Zn||Zn cells.Besides,Zn||hydrated vanadium oxide-based full batteries with the low-concentration organic electrolytes are also demonstrated with the high specific capacity of 173.8 mAh g^(-1)at 0.5 A g^(-1)and 64%capacity retention over 305 cycles and oriented Zn deposition.

Themis suppresses the effector function of CD8^(+)T cells in acute viral infection

CD8^(+)T cells play a central role in antiviral immune responses.Upon infection,naive CD8^(+)T cells differentiate into effector cells to eliminate virus-infected cells,and some of these effector cells further differentiate into memory cells to provide long-term protection after infection is resolved.Although extensively investigated,the underlying mechanisms of CD+T-cell differentiation remain incompletely understood.Themis is a T-cell-specific protein that plays critical roles in T-cell development.Recent studies using Themis T-cell conditional knockout mice also demonstrated that Themis is required to promote mature CD8^(+)T-cell homeostasis,cytokine responsiveness,and antibacterial responses.In this study,we used LCMV Armstrong infection as a probe to explore the role of Themis in viral infection.We found that preexisting CD8^(+)T-cell homeostasis defects and cytokine hyporesponsiveness do not impair viral clearance in Themis T-cell conditional knockout mice.Further analyses showed that in the primary immune response,Themis deficiency promoted the differentiation of CD8^(+)effector cells and increased their TNF and IFNy production.Moreover,Themis deficiency impaired memory precursor cell(MPEC)differentiation but promoted short-lived effector cell(SLEC)differentiation.Themis deficiency also enhanced effector cytokine production in memory CD8^(+)T cells while impairing central memory CD8^(+)T-cell formation.Mechanistically,we found that Themis mediates PD-1 expression and its signaling in effector CD8^(+)T cells,which explains the elevated cytokine production in these cells when Themis is disrupted.

Improved Corrosion Resistance of Selective Laser Melted Ti–5Cu Alloy Using Atomized Ti–5Cu Powder

The different types of metal powder used for selective laser melting(SLM) process would cause distinct corrosion behavior due to the uniformity of the obtained microstructure.The SLM-produced Ti–5Cu alloy using atomized Ti–5Cu metal powder(SLMed Ti–5Cu) in this work reveals a relatively uniform microstructure with overwhelming acicular α/α′ phase and shows great advantages on corrosion resistance compared with the SLM-produced Ti–5Cu alloy using the mixture powder(SLMedM Ti–5Cu).The effect of the micro-galvanic cells decreases due to the undetectable Ti2Cu phase in the microstructure of the SLMed Ti–5Cu.An apparent passivation behavior was observed for SLMed Ti–5Cu instead of severe pitting phenomenon for the SLMed-M Ti–5Cu.The charge transfer resistance of SLMed Ti–5Cu in this work is 10.09 ± 2.63 MΩ cm2, which is significantly higher than that of SLMed-M Ti–5Cu(4.76 MΩ cm2).The above result indicates the atomized Ti–5Cu powder plays an important role in the formation of the uniform microstructure of SLMed product, thereby enhancing its corrosion resistance in Hank’s solution at 37 ℃.

High electro-catalytic graphite felt/Mn O2composite electrodes for vanadium redox flow batteries

A mild and simple synthesis process for large-scale vanadium redox flow batteries(VRFBs)energy storage systems is desirable.A graphite felt/Mn O_2(GF-MNO)composite electrode with excellent electrocatalytic activity towards VO^(2+)/VO_2^+redox couples in a VRFB was synthesized by a one-step hydrothermal process.The resulting GF-MNO electrodes possess improved electrochemical kinetic reversibility of the vanadium redox reactions compared to pristine GF electrodes,and the corresponding energy efficiency and discharge capacity at 150 m A cm^(-2)are increased by 12.5%and 40%,respectively.The discharge capacity is maintained at 4.8 A h L^(-1)at the ultrahigh current density of 250 m A cm^(-2).Above all,80%of the energy efficiency of the GF-MNO composite electrodes is retained after 120 charge-discharge cycles at 150 m A cm^(-2).Furthermore,these electrodes demonstrated that more evenly distributed catalytic active sites were obtained from the Mn O_2particles under acidic conditions.The proposed synthetic route is facile,and the raw materials are low cost and environmentally friendly.Therefore,these novel GF-MNO electrodes hold great promise in large-scale vanadium redox flow battery energy storage systems.

Synthesis and Characterization of Carborane Bisphenol Resol Phenolic Resins with Ultrahigh Char Yield

Two carborane-containing resol phenolic resins（P1 and P2） with high boron content were synthesized via the reaction of carborane bisphenols（1 and 2） with formaldehyde in the presence of alkaline. HRMS results indicate that P1 is mainly composed of hydroxymethylated o-carborane bisphenols, the Mw of which was restrained around 500 due to the strong steric hindrance of o-carborane bisphenol. In contrast, the molecular weight of P2 was well regulated under various reaction conditions. The obtained resins were characterized with spectroscopic techniques including FTIR, 1H-NMR, ^13C-NMR, and 11B-NMR, which gave satisfactory results. TGA studies show that P2 shows char yield of 88.9% and 92.9% at 900 ℃ under nitrogen and air respectively. The imported carborane cage endows phenolic resin with ultrahigh char yield. Particularly, the char yield of the obtained carborane-containing phenolic resin under air is higher than that under nitrogen. FTIR and XRD confirm that the carborane cage could react with oxygen to form B2O3 at elevated temperatures, which postpones the thermal decomposition of phenolic resin and accounts for the high char yield.