Effects of mesenchymal stem cell on dopaminergic neurons,motor and memory functions in animal models of Parkinson's disease:a systematic review and meta-analysis

Parkinson’s disease is chara cterized by the loss of dopaminergic neurons in the substantia nigra pars com pacta,and although restoring striatal dopamine levels may improve symptoms,no treatment can cure or reve rse the disease itself.Stem cell therapy has a regenerative effect and is being actively studied as a candidate for the treatment of Parkinson’s disease.Mesenchymal stem cells are considered a promising option due to fewer ethical concerns,a lower risk of immune rejection,and a lower risk of teratogenicity.We performed a meta-analysis to evaluate the therapeutic effects of mesenchymal stem cells and their derivatives on motor function,memory,and preservation of dopamine rgic neurons in a Parkinson’s disease animal model.We searched bibliographic databases(PubMed/MEDLINE,Embase,CENTRAL,Scopus,and Web of Science)to identify articles and included only pee r-reviewed in vivo interve ntional animal studies published in any language through J une 28,2023.The study utilized the random-effect model to estimate the 95%confidence intervals(CI)of the standard mean differences(SMD)between the treatment and control groups.We use the systematic review center for laboratory animal expe rimentation’s risk of bias tool and the collaborative approach to meta-analysis and review of animal studies checklist for study quality assessment.A total of 33studies with data from 840 Parkinson’s disease model animals were included in the meta-analysis.Treatment with mesenchymal stem cells significantly improved motor function as assessed by the amphetamine-induced rotational test.Among the stem cell types,the bone marrow MSCs with neurotrophic factor group showed la rgest effect size(SMD[95%CI]=-6.21[-9.50 to-2.93],P=0.0001,I^(2)=0.0%).The stem cell treatment group had significantly more tyrosine hydroxylase positive dopamine rgic neurons in the striatum([95%CI]=1.04[0.59 to 1.49],P=0.0001,I^(2)=65.1%)and substantia nigra(SMD[95%CI]=1.38[0.89 to 1.87],P=0.0001,I^(2)=75.3%),indicating a protective effect on dopaminergic neurons.Subgroup analysis of the amphetamine-induced rotation test showed a significant reduction only in the intracranial-striatum route(SMD[95%CI]=-2.59[-3.25 to-1.94],P=0.0001,I^(2)=74.4%).The memory test showed significant improvement only in the intravenous route(SMD[95%CI]=4.80[1.84 to 7.76],P=0.027,I^(2)=79.6%).Mesenchymal stem cells have been shown to positively impact motor function and memory function and protect dopaminergic neurons in preclinical models of Parkinson’s disease.Further research is required to determine the optimal stem cell types,modifications,transplanted cell numbe rs,and delivery methods for these protocols.

Short- and long-term outcomes of surgical treatment in patients with intestinal Behcet’s disease

BACKGROUND Behcet’s disease(BD),a chronic vasculitic disorder affecting multiple organs,is characterized by recurrent oral and genital ulcers,arthritis,vasculitis,and intes-tinal ulcers.Although intestinal involvement of BD is common in East Asia,the efficacy and long-term outcomes of surgical treatment of intestinal BD still remain to be established.AIM To evaluate the postoperative clinical course of intestinal BD and determine factors associated with its recurrence.METHODS Data from patients who underwent surgical treatment for intestinal BD between January 2010 and August 2021 were retrospectively reviewed.Patients’demo-graphics,clinical features,postoperative course,complications,and follow-up data were evaluated.RESULTS We analyzed 39 surgeries in 31 patients.The mean patient age was 45.1 years,and the mean interval between the diagnosis of intestinal BD and surgical treatment was 4.9 years(range 1.0-8.0 years).The most common indication for surgery was medical intractability(n=16,41.0%),followed by fistula or abscess(n=11,28.2%).Laparoscopic approaches were used in 19 patients(48.7%),and 5 patients(12.8%)underwent emergency surgeries.The most common surgical procedure was ileocecal resection(n=18,46.2%),followed by right colectomy(n=11,28.2%).A diverting stoma was created in only one patient(2.6%).During a mean follow-up period of 45(range 8-72)months,eight cases(20.5%)of recurrence in five patients required reoperation.The interval between operations was 12.1 months(range 6.3-17.8 mo).Four patients(10.3%)experienced recurrence within 1 year postoperatively,and all eight recurrences occurred within 2 years of the initial surgery.The reoperation rates at 1 and 3 years were 10.3%and 20.5%,respectively.A redo ileocolic anastomosis was performed in all recurrent cases.In multivariate Cox regression analysis,emergency surgery[hazard ratio(HR)9.357,95%confidence interval(CI):1.608-54.453,P=0.013]and elevated C-reactive protein(CRP)levels(HR 1.154,95%CI:1.002–1.328,P=0.047),but not medication use,were predictors of recurrence.CONCLUSION Surgical resection is a feasible treatment option for complicated BD.Reoperation is associated with severe inflam-matory conditions,reflected by increased CRP levels and the requirement for emergency surgery.

Neural Wiskott-Aldrich syndrome protein(N-WASP)promotes distant metastasis in pancreatic ductal adenocarcinoma via activation of LOXL2

Pancreatic ductal adenocarcinoma(PDAC)is one of the most aggressive solid malignancies.A specific mechanism of its metastasis has not been established.In this study,we investigated whether Neural Wiskott-Aldrich syndrome protein(N-WASP)plays a role in distant metastasis of PDAC.We found that N-WASP is markedly expressed in clinical patients with PDAC.Clinical analysis showed a notably more distant metastatic pattern in the N-WASP-high group compared to the N-WASP-low group.N-WASP was noted to be a novel mediator of epithelialmesenchymal transition(EMT)via gene expression profile studies.Knockdown of N-WASP in pancreatic cancer cells significantly inhibited cell invasion,migration,and EMT.We also observed positive association of lysyl oxidase-like 2(LOXL2)and focal adhesion kinase(FAK)with the N-WASP-mediated response,wherein EMT and invadopodia function were modulated.Both N-WASP and LOXL2 depletion significantly reduced the incidence of liver and lung metastatic lesions in orthotopic mouse models of pancreatic cancer.These results elucidate a novel role for N-WASP signaling associated with LOXL2 in EMT and invadopodia function,with respect to regulation of intercellular communication in tumor cells for promoting pancreatic cancer metastasis.These findings may aid in the development of therapeutic strategies against pancreatic cancer.

Revealing the influence of in-situ formed LiCl on garnet/Li interface for dendrite-free solid-state batteries

Inadequate interfacial contact between lithium and solid-state electrolytes(SSEs)leads to elevated impedance and the growth of lithium dendrites,presenting significant obstacles to the practical viability of solid-state batteries(SSBs).To ameliorate interfacial contact,optimizing the surface treatment of SSEs has been widely adopted.However,the formation of LiCl through acid treatment,an equally crucial factor impacting SSB performance,has received limited attention,leaving its underlying mechanism unclear.Our study aims to shed light on SSE characteristics following LiCl formation and the removal of Li_(2)CO_(3) through acid treatment.We seek to establish quantifiable links between SSE surface structure and SSB performance,focusing on interfacial resistance,current distribution,critical current density(CCD),and lithium deposition.The formation of LiCl,occurring as Li_(2)CO_(3) is removed through acid treatment,effectively mitigates lithium dendrite formation on SSE surfaces.This action inhibits electron injection and reduces the diffusion rate of Li atoms.Simultaneously,acid treatment transforms the SSE surface into a lithiophilic state by eliminating surface Li_(2)CO_(3).Consequently,the interfacial resistance between lithium and SSEs substantially decreases from 487.67 to 35.99Ωcm^(2) at 25°C.This leads to a notably high CCD of 1.3 mA cm^(-2) and a significantly extended cycle life of 1,000 h.Furthermore,in full SSBs incorporating LiCoO_(2)cathodes and acid-treated garnet SSEs,we observe exceptional cyclability and rate capability.Our findings highlight that acid treatment not only establishes a fundamental relationship between SSE surfaces and battery performance but also offers an effective strategy for addressing interfacial challenges in SSBs.

A Solvent-Free Covalent Organic Framework Single-Ion Conductor Based on Ion-Dipole Interaction for All-Solid-State Lithium Organic Batteries

Single-ion conductors based on covalent organic frameworks(COFs)have garnered attention as a potential alternative to currently prevalent inorganic ion conductors owing to their structural uniqueness and chemical versatility.However,the sluggish Li+conduction has hindered their practical applications.Here,we present a class of solvent-free COF single-ion conductors(Li-COF@P)based on weak ion-dipole interaction as opposed to traditional strong ion-ion interaction.The ion(Li+from the COF)-dipole(oxygen from poly(ethylene glycol)diacrylate embedded in the COF pores)interaction in the Li-COF@P promotes ion dissociation and Li+migration via directional ionic channels.Driven by this single-ion transport behavior,the Li-COF@P enables reversible Li plating/stripping on Li-metal electrodes and stable cycling performance(88.3%after 2000 cycles)in organic batteries(Li metal anode||5,5’-dimethyl-2,2’-bis-p-benzoquinone(Me2BBQ)cathode)under ambient operating conditions,highlighting the electrochemical viability of the Li-COF@P for all-solid-state organic batteries.

Upcycling plastic wastes into value-added products via electrocatalysis and photoelectrocatalysis

Plastic,renowned for its versatility,durability,and cost-effectiveness,is indispensable in modern society.Nevertheless,the annual production of nearly 400 million tons of plastic,coupled with a recycling rate of only 9%,has led to a monumental environmental crisis.Plastic recycling has emerged as a vital response to this crisis,offering sustainable solutions to mitigate its environmental impact.Among these recycling efforts,plastic upcycling has garnered attention,which elevates discarded plastics into higher-value products.Here,electrocatalytic and photoelectrocatalytic treatments stand at the forefront of advanced plastic upcycling.Electrocatalytic or photoelectrocatalytic treatments involve chemical reactions that facilitate electron transfer through the electrode/electrolyte interface,driven by electrical or solar energy,respectively.These methods enable precise control of chemical reactions,harnessing potential,current density,or light to yield valuable chemical products.This review explores recent progress in plastic upcycling through electrocatalytic and photoelectrocatalytic pathways,offering promising solutions to the plastic waste crisis and advancing sustainability in the plastics industry.

Pyrometallurgical recycling of end-of-life lithium-ion batteries

The global importance of lithium-ion batteries(LIBs)has been increasingly underscored with the advancement of high-performance energy storage technologies.However,the end-of-life of these batteries poses significant challenges from environmental,economic,and resource management perspectives.This review paper focuses on the pyrometallurgy-based recycling process of lithium-ion batteries,exploring the fundamental understanding of this process and the importance of its optimization.Centering on the high energy consumption and emission gas issues of the pyrometallurgical recycling process,we systematically analyzed the capital-intensive nature of this process and the resulting technological characteristics.Furthermore,we conducted an in-depth discussion on the future research directions to overcome the existing technological barriers and limitations.This review will provide valuable insights for researchers and industry stakeholders in the battery recycling field.

Extraction of intersecting palm-vein and palmprint features for cancellable identity verification

A novel method based on the cross-modality intersecting features of the palm-vein and the palmprint is proposed for identity verification.Capitalising on the unique geometrical relationship between the two biometric modalities,the cross-modality intersecting points provides a stable set of features for identity verification.To facilitate flexibility in template changes,a template transformation is proposed.While maintaining non-invertibility,the template transformation allows transformation sizes beyond that offered by the con-ventional means.Extensive experiments using three public palm databases are conducted to verify the effectiveness the proposed system for identity recognition.

Guest Editorial:Special issue on advances in representation learning for computer vision

Deep learning has been a catalyst for a transformative revo-lution in machine learning and computer vision in the past decade.Within these research domains,methods grounded in deep learning have exhibited exceptional performance across a spectrum of tasks.The success of deep learning methods can be attributed to their capability to derive potent representations from data,integral for a myriad of downstream applications.These representations encapsulate the intrinsic structure,fea-tures,or latent variables characterising the underlying statistics of visual data.Despite these achievements,the challenge per-sists in effectively conducting representation learning of visual data with deep models,particularly when confronted with vast and noisy datasets.This special issue is a dedicated platform for researchers worldwide to disseminate their latest,high-quality articles,aiming to enhance readers'comprehension of the principles,limitations,and diverse applications of repre-sentation learning in computer vision.

Resonance From the Past to the Future:Mythological Metaphors in Chinese Science Fiction Films

This paper is centered on the extent to which contemporary Chinese science fiction is related to ancient Chinese mythologies according to the previous scholarly discussion and how these ancient mythologies are utilized specifically in the futuristic narratives of modern Chinese science fiction.By referring to academic dialogues,this paper argues that ancient mythologies can be recreated in modern science fiction and create modern mythologies in futuristic narratives to present or deal with modern human fears.Based on this argument,this paper then continues to explore what kinds of modern mythologies science fiction might deliver.The Chinese film The Wandering Earth(2019)will be discussed in terms of its mythological symbols and metaphors.This paper proposes a new approach through which to reconnect past stories with futuristic narratives and builds a frame in which to contextualize ancient mythologies in contemporary Chinese culture.

Monogenic features of urolithiasis: A comprehensive review

Objective: Urolithiasis formation has been attributed to environmental and dietary factors. However, evidence is accumulating that genetic background can contribute to urolithiasis formation. Advancements in the identification of monogenic causes using high-throughput sequencing technologies have shown that urolithiasis has a strong heritable component.Methods: This review describes monogenic factors implicated in a genetic predisposition to urolithiasis. Peer-reviewed journals were evaluated by a PubMed search until July 2023 to summarize disorders associated with monogenic traits, and discuss clinical implications of identification of patients genetically susceptible to urolithiasis formation.Results: Given that more than 80% of urolithiases cases are associated with calcium accumulation, studies have focused mainly on monogenetic contributors to hypercalciuric urolithiases, leading to the identification of receptors, channels, and transporters involved in the regulation of calcium renal tubular reabsorption. Nevertheless, available candidate genes and linkage methods have a low resolution for evaluation of the effects of genetic components versus those of environmental, dietary, and hormonal factors, and genotypes remain undetermined in the majority of urolithiasis formers.Conclusion: The pathophysiology underlying urolithiasis formation is complex and multifactorial, but evidence strongly suggests the existence of numerous monogenic causes of urolithiasis in humans.

Long-term outcome of stem cell transplantation with and without anti-tumor necrotic factor therapy in perianal fistula with Crohn’s disease

BACKGROUND Stem cell transplantation is a promising therapeutic option for curing perianal fistula in Crohn’s disease(CD).Anti-tumor necrotic factor(TNF)therapy combined with drainage procedure is effective as well.However,previous studies are limited to proving whether the combination treatment of biologics and stem cell transplantation improves the effect of fistula closure.AIM This study aimed to evaluate the long-term outcomes of stem cell transplantation and compare Crohn’s perianal fistula(CPF)closure rates after stem cell transplantation with and without anti-TNF therapy,and to identify the factors affecting CPF closure and recurrence.METHODS The patients with CD who underwent stem cell transplantation for treating perianal fistula in our institution between Jun 2014 and December 2022 were enrolled.Clinical data were compared according to anti-TNF therapy and CPF closure.RESULTS A total of 65 patients were included.The median age of females was 26 years(range:21-31)and that of males was 29(44.6%).The mean follow-up duration was 65.88±32.65 months,and complete closure was observed in 50(76.9%)patients.The closure rates were similar after stem cell transplantation with and without anti-TNF therapy(66.7%vs 81.6%at 3 year,P=0.098).The patients with fistula closure had short fistulous tract and infrequent proctitis and anorectal stricture(P=0.027,0.002,and 0.008,respectively).Clinical factors such as complexity,number of fistulas,presence of concurrent abscess,and medication were not significant for closure.The cumulative 1-,2-,and 3-year closure rates were 66.2%,73.8%,and 75.4%,respectively.CONCLUSION Anti-TNF therapy does not increase CPF closure rates in patients with stem cell transplantation.However,both refractory and non-refractory CPF have similar closure rates after additional anti-TNF therapy.Fistulous tract length,proctitis,and anal stricture are risk factors for non-closure in patients with CPF after stem cell transplantation.

Direct 4D printing of functionally graded hydrogel networks for biodegradable,untethered,and multimorphic soft robots

Recent advances in functionally graded additive manufacturing(FGAM)technology have enabled the seamless hybridization of multiple functionalities in a single structure.Soft robotics can become one of the largest beneficiaries of these advances,through the design of a facile four-dimensional(4D)FGAM process that can grant an intelligent stimuli-responsive mechanical functionality to the printed objects.Herein,we present a simple binder jetting approach for the 4D printing of functionally graded porous multi-materials(FGMM)by introducing rationally designed graded multiphase feeder beds.Compositionally graded cross-linking agents gradually form stable porous network structures within aqueous polymer particles,enabling programmable hygroscopic deformation without complex mechanical designs.Furthermore,a systematic bed design incorporating additional functional agents enables a multi-stimuli-responsive and untethered soft robot with stark stimulus selectivity.The biodegradability of the proposed 4D-printed soft robot further ensures the sustainability of our approach,with immediate degradation rates of 96.6%within 72 h.The proposed 4D printing concept for FGMMs can create new opportunities for intelligent and sustainable additive manufacturing in soft robotics.

Pain Efficacy of a Home-Based Low-Intensity Continuous Ultrasound Stimulator for Knee Arthritis: A Single-Arm, Open-Label, Prospective Clinical Trial

1) Background: Osteoarthritis (OA) is defined as a degenerative joint disease that mainly affects the bone. This study aims to evaluate the effect of low-intensity continuous ultrasound (LICUS) treatment on the knee of osteoarthritis patients through home-based intervention using the LICUS medical device. 2) Methods: The clinical trials were designed in a single-arm, open-label, and intervention study. Thirty-five participants, including those who dropped out (12%), were screened and enrolled. The patients received LICUS (1.1 MHz, 1.5 W/cm2, collimated beams) on the knee by the instructions of the investigator at home (5 min/session, 3 times/day, for four-weeks). Outcome measures were assessed using the Visual Analog Scale (VAS) as a primary endpoint and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) as a secondary endpoint to evaluate pain relief and functional recovery of the knee between pre-treatment (baseline) and post-treatment (four-weeks). 3) Results: Knee pain scores measured using the VAS and WOMAC indices were significantly reduced after a four-week treatment with LICUS compared to baseline. Knee stiffness and functional capacity were significantly reduced after the LICUS application. In addition, there were no reports of adverse effects during the study period. 4) Conclusion: Long-term and home-based application of LICUS can be recommended as an alternative option for the treatment of OA patients, as evidenced by the effect of pain relief and knee function recovery.

Fine-tuning electronic structure of N-doped graphitic carbon-supported Co-and Fe-incorporated Mo_(2)C to achieve ultrahigh electrochemical water oxidation activity

Mo_(2)C is an excellent electrocatalyst for hydrogen evolution reaction(HER).However,Mo_(2)C is a poor electrocatalyst for oxygen evolution reaction(OER).Herein,two different elements,namely Co and Fe,are incorporated in Mo_(2)C that,therefore,has a finely tuned electronic structure,which is not achievable by incorporation of any one of the metals.Consequently,the resulting electrocatalyst Co_(0.8)Fe_(0.2)-Mo_(2)C-80 displayed excellent OER catalytic performance,which is evidenced by a low overpotential of 214.0(and 246.5)mV to attain a current density of 10(and 50)mA cm^(-2),an ultralow Tafel slope of 38.4 mV dec^(-1),and longterm stability in alkaline medium.Theoretical data demonstrates that Co_(0.8)Fe_(0.2)-Mo_(2)C-80 requires the lowest overpotential(1.00 V)for OER and Co centers to be the active sites.The ultrahigh catalytic performance of the electrocatalyst is attributed to the excellent intrinsic catalytic activity due to high Brunauer-Emmett-Teller specific surface area,large electrochemically active surface area,small Tafel slope,and low chargetransfer resistance.

A Review of Rechargeable Zinc-Air Batteries:Recent Progress and Future Perspectives

Zinc-air batteries(ZABs)are gaining attention as an ideal option for various applications requiring high-capacity batteries,such as portable electronics,electric vehicles,and renewable energy storage.ZABs offer advantages such as low environmental impact,enhanced safety compared to Li-ion batteries,and cost-effectiveness due to the abundance of zinc.However,early research faced challenges due to parasitic reactions at the zinc anode and slow oxygen redox kinetics.Recent advancements in restructuring the anode,utilizing alternative electrolytes,and developing bifunctional oxygen catalysts have significantly improved ZABs.Scientists have achieved battery reversibility over thousands of cycles,introduced new electrolytes,and achieved energy efficiency records surpassing 70%.Despite these achievements,there are challenges related to lower power density,shorter lifespan,and air electrode corrosion leading to performance degradation.This review paper discusses different battery configurations,and reaction mechanisms for electrically and mechanically rechargeable ZABs,and proposes remedies to enhance overall battery performance.The paper also explores recent advancements,applications,and the future prospects of electrically/mechanically rechargeable ZABs.

RUFY4 deletion prevents pathological bone loss by blocking endo-lysosomal trafficking of osteoclasts

Mature osteoclasts degrade bone matrix by exocytosis of active proteases from secretory lysosomes through a ruffled border.However,the molecular mechanisms underlying lysosomal trafficking and secretion in osteoclasts remain largely unknown.Here,we show with GeneChip analysis that RUN and FYVE domain-containing protein 4(RUFY4)is strongly upregulated during osteoclastogenesis.Mice lacking Rufy4 exhibited a high trabecular bone mass phenotype with abnormalities in osteoclast function in vivo.Furthermore,deleting Rufy4 did not affect osteoclast differentiation,but inhibited bone-resorbing activity due to disruption in the acidic maturation of secondary lysosomes,their trafficking to the membrane,and their secretion of cathepsin K into the extracellular space.Mechanistically,RUFY4 promotes late endosome-lysosome fusion by acting as an adaptor protein between Rab7 on late endosomes and LAMP2 on primary lysosomes.Consequently,Rufy4-deficient mice were highly protected from lipopolysaccharide-and ovariectomy-induced bone loss.Thus,RUFY4 plays as a new regulator in osteoclast activity by mediating endo-lysosomal trafficking and have a potential to be specific target for therapies against bone-loss diseases such as osteoporosis.

Catalpa bignonioides extract improves exercise performance through regulation of growth and metabolism in skeletal muscles

Objective:To evaluate the effects of Catalpa bignonioides fruit extract on the promotion of muscle growth and muscular capacity in vitro and in vivo.Methods:Cell viability was measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.Cell proliferation was assessed using a 5-bromo-2’-deoxyuridine(BrdU)assay kit.Western blot analysis was performed to determine the protein expressions of related factors.The effects of Catalpa bignonioides extract were investigated in mice using the treadmill exhaustion test and whole-limb grip strength assay.Chemical composition analysis was performed using high-performance liquid chromatography(HPLC).Results:Catalpa bignonioides extract increased the proliferation of C2C12 mouse myoblasts by activating the Akt/mTOR signaling pathway.It also induced metabolic changes,increasing the number of mitochondria and glucose metabolism by phosphorylating adenosine monophosphate-activated protein kinase.In an in vivo study,the extract-treated mice showed improved motor abilities,such as muscular endurance and grip strength.Additionally,HPLC analysis showed that vanillic acid may be the main component of the Catalpa bignonioides extract that enhanced muscle strength.Conclusions:Catalpa bignonioides improves exercise performance through regulation of growth and metabolism in skeletal muscles,suggesting its potential as an effective natural agent for improving muscular strength.

Analysis of China’s Sports Diplomacy Path from the Perspective of Soft Power

“When a country prospers,sports thrive.”Building a strong sports country is an important connotation of realizing the great rejuvenation of the Chinese nation and building a moderately prosperous society in all respects.Actively engaging in sports diplomacy from the perspective of soft power can expand a country’s international influence,promote friendly cooperation between nations,and enhance the overall image of the country.This article analyzes the concepts of soft power and sports diplomacy and explores the path of China’s sports diplomacy from four aspects:promoting diverse subjects,expanding propaganda channels,optimizing underlying design,and actively participating in competitions.

Functionally graded structure of a nitride-strengthened Mg_(2)Si-based hybrid composite

The ex-situ incorporation of the secondary SiC reinforcement,along with the in-situ incorporation of the tertiary and quaternary Mg_(3)N_(2) and Si_(3)N_(4) phases,in the primary matrix of Mg_(2)Si is employed in order to provide ultimate wear resistance based on the laser-irradiation-induced inclusion of N_(2) gas during laser powder bed fusion.This is substantialized based on both the thermal diffusion-and chemical reactionbased metallurgy of the Mg_(2)Si–SiC/nitride hybrid composite.This study also proposes a functional platform for systematically modulating a functionally graded structure and modeling build-direction-dependent architectonics during additive manufacturing.This strategy enables the development of a compositional gradient from the center to the edge of each melt pool of the Mg_(2)Si–SiC/nitride hybrid composite.Consequently,the coefficient of friction of the hybrid composite exhibits a 309.3%decrease to–1.67 compared to–0.54 for the conventional nonreinforced Mg_(2)Si structure,while the tensile strength exhibits a 171.3%increase to 831.5 MPa compared to 485.3 MPa for the conventional structure.This outstanding mechanical behavior is due to the(1)the complementary and synergistic reinforcement effects of the SiC and nitride compounds,each of which possesses an intrinsically high hardness,and(2)the strong adhesion of these compounds to the Mg_(2)Si matrix despite their small sizes and low concentrations.