Epitaxially Grown Ru Clusters-Nickel Nitride Heterostructure Advances Water Electrolysis Kinetics in Alkaline and Seawater Media

The epitaxial heterostructure can be rationally designed based on the in situ growth of two compatible phases with lattice similarity,in which the modulated electronic states and tuned adsorption behaviors are conducive to the enhancement of electrocatalytic activity.Herein,theoretical simulations first disclose the charge transfer trend and reinforced inherent electron conduction around the epitaxial heterointerface between Ru clusters and Ni_(3)N substrate(cRu-Ni_(3)N),thus leading to the optimized adsorption behaviors and reduced activation energy barriers.Subsequently,the defectrich nanosheets with the epitaxially grown cRu-Ni_(3)N heterointerface are successfully constructed.Impressively,by virtue of the superiority of intrinsic activity and reaction kinetics,such unique epitaxial heterostructure exhibits remarkable bifunctional catalytic activity toward electrocatalytic OER(226 mV@20 mA cm^(−2))and HER(32 mV@10 mA cm^(−2))in alkaline media.Furthermore,it also shows great application prospect in alkaline freshwater and seawater splitting,as well as solar-to-hydrogen integrated system.This work could provide beneficial enlightenment for the establishment of advanced electrocatalysts with epitaxial heterointerfaces.

Layered manganese phosphorus trisulfides for high-performance lithium-ion batteries and the storage mechanism

Although advanced anode materials for the lithium-ion battery have been investigated for decades,a reliable,high-capacity,and durable material that can enable a fast charge remains elusive.Herein,we report that a metal phosphorous trichalcogenide of MnPS_(3)(manganese phosphorus trisulfide),endowed with a unique and layered van der Waals structure,is highly beneficial for the fast insertion/extraction of alkali metal ions and can facilitate changes in the buffer volume during cycles with robust structural stability.The few-layered MnPS_(3)anodes displayed the desirable specific capacity and excellent rate chargeability owing to their good electronic and ionic conductivities.When assembled as a half-cell lithium-ion battery,a high reversible capacity of 380 mA h g^(−1)was maintained by the MnPS_(3)after 3000 cycles at a high current density of 4 A g^(−1),with a capacity retention of close to or above 100%.In full-cell testing,a reversible capacity of 450 mA h g^(−1)after 200 cycles was maintained as well.The results of in-situ TEM revealed that MnPS_(3)nanoflakes maintained a high structural integrity without exhibiting any pulverization after undergoing large volumetric expansion for the insertion of a large number of lithium ions.Their kinetics of lithium-ion diffusion,stable structure,and high pseudocapacitance contributed to their comprehensive performance,for example,a high specific capacity,rapid charge-discharge,and long cyclability.MnPS_(3)is thus an efficient anode for the next generation of batteries with a fast charge/discharge capability.

Tuning Active Metal Atomic Spacing by Filling of Light Atoms and Resulting Reversed Hydrogen Adsorption-Distance Relationship for Efficient Catalysis

Precisely tuning the spacing of the active centers on the atomic scale is of great significance to improve the catalytic activity and deepen the understanding of the catalytic mechanism,but still remains a challenge.Here,we develop a strategy to dilute catalytically active metal interatomic spacing(d_(M-M))with light atoms and discover the unusual adsorption patterns.For example,by elevating the content of boron as interstitial atoms,the atomic spacing of osmium(d_(Os-Os))gradually increases from 2.73 to 2.96?.More importantly,we find that,with the increase in dOs-Os,the hydrogen adsorption-distance relationship is reversed via downshifting d-band states,which breaks the traditional cognition,thereby optimizing the H adsorption and H_2O dissociation on the electrode surface during the catalytic process;this finally leads to a nearly linear increase in hydrogen evolution reaction activity.Namely,the maximum dOs-Os of 2.96?presents the optimal HER activity(8 mV@10 mA cm^(-2))in alkaline media as well as suppressed O adsorption and thus promoted stability.It is believed that this novel atomic-level distance modulation strategy of catalytic sites and the reversed hydrogen adsorption-distance relationship can shew new insights for optimal design of highly efficient catalysts.

Unraveling the reaction reversibility and structure stability of nickel sulfide anodes for lithium ion batteries

The electrochemical performance of lithium-ion batteries,i.e.specific capacity and cyclability,is primarily determined by chemical reversibility and structural stability of the electrodes in cycling.Here we have investigated the fundamental reaction behaviors of nickel sulfide(NixSy)as lithium-ion battery anodes by in-situ TEM.We find that Ni_(3)S_(2)is the electrochemically stable phase,which appears in the first cycle of the NixSyanode.From the second cycle,conversion between Ni_(3)S_(2)and Li_(2)S/Ni is the dominant electrochemical reaction.In lithiation,the NixSynanoparticles evolve into a mixture of Ni nanocrystals embedded in Li_(2)S matrix,which form a porous structure upon full lithiation,and with the recrystallization of the Ni_(3)S_(2)phase in delithiation,a compact and interconnected network is built.Structural stability in cycles is susceptible to particle size and substrate restraint.Carbon substrate can certainly improve the tolerance for size-dependent pulverization of NixSynanoparticles.When NixSynanoparticle exceeds the critical size value,the morphology of the particle is no longer well maintained even under the constraints of the carbon substrate.This work deepens the understanding of electrochemical reaction behavior of conversiontype materials and helps to rational design of high-energy density battery anodes.

ZIF-Mediated Anchoring of Co species on N-doped Carbon Nanorods as an Efficient Cathode Catalyst for Zn-Air Batteries

Developing efficient oxygen reduction reaction(ORR)catalyst is essential for the practical application of Zn-air batteries(ZABs).In this contribution,we develop a novel zeolitic imidazolate framework(ZIF)-mediated strategy to anchor Co species on N-doped carbon nanorods for efficient ORR.Featuring ultrahigh N-doping(10.29 at.%),monodisperse Co nanocrystal decoration,and well-dispersed Co-N_(x)functionalization,the obtained Co-decorated N-doped carbon nanorods(Co@NCNR)exhibit a decent ORR performance comparable to commercial Pt/C in alkaline media.Aqueous ZABs have been assembled using Co@NCNR as the cathode catalyst.The assembled ZABs manifest high initial open-circuit voltage as well as high energy density.In addition,the Co@NCNR also demonstrates ideal ORR performance in quasi-solid-state ZABs.

LIM1863 is useful to explore collective cancer cell migration,and the group of heterogeneous cells undergoing collective migration behaves like a supracellular unit

Collective cancer cell migration(CCCM)and epithelial-to-mesenchymal transition(EMT)play key roles in metastasis.This study reports that the colorectal carcinoma cell line LIM1863 is useful for the study of CCCM and EMT.Methods:Hematoxylin and eosin staining,scanning electron microscopy,transmission electron microscopy,and western blot analysis were performed.Results:LIM1863 automatically grew as spheroids in suspension and had important typical epithelial properties,including several layers of cells arranged around a central lumen,apical-basal polarity,and types of cell-cell junctions.Treatment with a combination of both TGF beta 1 and TNF alpha induced definite and distinct EMT,a spheroid changing phenotype to form a monolayer high-confluent patch without lumen,without polarity.Spontaneous CCCM occurred in spheroids.Flat EMT cells adhered to the base of a dish,exhibited persistent movement as a cluster of cells,and then shed,resulting in a cluster.All cells from one cluster undergoing CCCM died.Otherwise,all cells undergoing EMT disappeared and almost all cells located in the cell reservoir survived and proliferated.Conclusion:LIM1863 is an excellent cell line to study CCCM and EMT.The group of heterogeneous cells undergoing CCCM behaves like a supracellular unit.

Engineering Mesoporous Structure in Amorphous Carbon Boosts Potassium Storage with High Initial Coulombic Efficiency

Amorphous carbon shows great potential as an anode material for high-performance potassium-ion batteries;however,its abundant defects or micropores generally capture K ions,thus resulting in high irreversible capacity with low initial Coulombic efficiency(ICE)and limited practical application.Herein,pore engineering via a facile self-etching strategy is applied to achieve mesoporous carbon(meso-C)nanowires with interconnected framework.Abundant and evenly distributed mesopores could provide short K^+ pathways for its rapid diffusion.Compared to microporous carbon with highly disordered structure,the meso-C with Zn-catalyzed short-range ordered structure enables more K^+to reversibly intercalate into the graphitic layers.Consequently,the mesoC shows an increased capacity by ~100 mAh g^-1 at 0.1 A g^-1,and the capacity retention is 70.7% after 1000 cycles at 1 A g^-1.Multiple in/ex situ characterizations reveal the reversible structural changes during the charging/discharging process.Particularly,benefiting from the mesoporous structure with reduced specific surface area by 31.5 times and less defects,the meso-C generates less irreversible capacity with high ICE up to 76.7%,one of the best reported values so far.This work provides a new perspective that mesopores engineering can effectively accelerate K^+ diffusion and enhance K^+ adsorption/intercalation storage.

NaPDR1 and NaPDR1-like are essential for the resistance of Nicotiana attenuata against fungal pathogen Alternaria alternata

Pleiotropic drug resistance(PDR) transporters are widely distributed membrane proteins catalyzing the export or import of a diverse array of molecules, and are involved in many plant responses to biotic and abiotic stresses. However, it is unclear whether PDRs are involved in Nicotiana attenuata resistance to the necrotic fungal pathogen Alternaria alternata. In this study, transcriptional levels of both NaPDR1 and NaPDR1-like were highly induced in N. attenuata leaves after A. alternata inoculation. Interestingly,silencing NaPDR1 or NaPDR1-like individually had little effect on N. attenuata resistance to A. alternata;however, when both genes were co-silenced plants became highly susceptible to the fungus, which was associated with elevated JA and ethylene responses. Neither NaPDR1 nor NaPDR1-like was significantly elicited by exogenous treatment with methyl jasmonate(MeJA), whereas both were highly induced by ethylene. The elicitation levels of both genes by A. alternata were significantly reduced in plants with impaired JA or ethylene signaling pathways. Thus, we conclude that both NaPDR1 and NaPDR1-like function redundantly to confer resistance against A. alternata in N. attenuata, and the elicitation of the transcripts of both genes by the fungus is partially dependent on ethylene and jasmonate signaling.

A patatin-like protein synergistically regulated by jasmonate and ethylene signaling pathways plays a negative role in Nicotiana attenuata resistance to Alternaria alternata

Although patatin was initially identified as a major storage protein in potato tubers, patatin-like proteins(PLPs) have been recently reported to be widely present in many plant species and shown to be involved in plant-pathogen interactions. However, it is not clear whether PLPs are involved in Nicotiana attenuata resistance against the necrotrophic fungal pathogen, Alternaria alternata. In this study we identified a NaPLP gene, whose expression was highly elicited by A. alternata inoculation. Silencing NaPLP enhanced N. attenuata resistance to A. alternata, which was associated with higher induction levels of JA and ethylene biosynthetic genes, NaACS1, NaACO1 and NaLOX3. The induction of NaPLP expression by the fungus was abolished in JA-deficient plants and significantly reduced in ethylene-insensitive plants. In addition, NaPLP transcripts were highly induced by exogenous treatment with either methyl jasmonate(MeJA) or ethephon. Co-treatment with MeJA and ethephon led to a much higher induction level of NaPLP transcripts, and this synergistic induction was largely dependent on endogenous JA and ethylene signaling pathways. Thus, we conclude that the NaPLP gene is elicited by A. alternata via JA and ethylene signaling pathways in a synergistic way; however, unlike other JA-and ethylene-induced defense genes,NaPLP negatively affects plant resistance to the fungus likely by suppressing JA and ethylene biosynthetic gene expression.

Involvement of NAC transcription factor NaNAC29 in Alternaria alternata resistance and leaf senescence in Nicotiana attenuata

NAC-LIKE,ACTIVATED BY AP3/PI(NAP)is a NAC transcription factor regulating leaf senescence in Arabidopsis thaliana.In wild tobacco Nicotiana attenuata,a nuclear localized NAC transcription factor NaNAC29 was identified to be highly elicited after inoculation of Alternaria alternata,a notorious necrotic fungus on tobacco species.The NaNAC29 possesses similar tertiary structure to NAP with 60%amino acid identity.However,it remains unknown the role of NaNAC29 in plant defense responses to A.alternata and leaf senescence in N.attenuata.In this paper,Defensin-like protein 1(NaDLP1)was highly induced in N.attenuata after A.alternata inoculation and bigger lesions were developed in NaDLP1-silenced plants.Interestingly,A.alternata-induced NaDLP1 was reduced by 76%in VIGS NaNAC29 plants and by 61%in JA deficient irAOC plants at 3 days post inoculation.The regulation of NaDLP1 expression by NaNAC29 was clearly independent on JA pathway,since exogenous methyl jasmonate treatment could not complement the induction levels of NaDLP1 in NaNAC29-silenced plants to the levels in WT plants.Otherwise,the expression of NaNAC29 was low expressed in young leaves but highly in senescent leaves and darktreated leaves.NaNAC29-silenced plants,which were generated by virus-induced gene silencing(VIGS NaNAC29),showed delayed senescence phenotype.In addition,constitutive over-expression of NaNAC29 in A.thaliana could rescue the delayed-senescence phenotype of nap and caused precocious leaf senescence of wild-type Col-0 plants.All the data above demonstrate that NaNAC29 is a NAP homolog in N.attenuata participating in the defense responses to A.alternata by regulation of a defensin protein NaDLP1 and promoting leaf senescence.

Hierarchical cobalt-molybdenum layered double hydroxide arrays power efficient oxygen evolution reaction

Transition metal-based layered double hydroxides(LDHs)have been capable of working efficiently as catalysts in the basic oxygen evolution reaction(OER)for sustaining hydrogen production of alkaline water electrolysis.Nevertheless,exploring new LDH-based electrocatalysts featuring both remarkable activity and good stability is still in high demand,which is pivotal for comprehensive understanding and impressive improvement of the sluggish OER kinetics.Here,a series of bimetallic(Co and Mo)LDH arrays were designed and fabricated via a facile and controlled strategy by incorporating a Mo source into presynthesized Co-based metal-organic framework(MOF)arrays on carbon cloth(CC),named as ZIF-67/CC arrays.We found that tuning the Mo content resulted in gradual differences in the structural properties,surface morphology,and chemical states of the resulting catalysts,namely CoMox-LDH/CC(x representing the added weight of the Mo source).Gratifyingly,the best-performing CoMo_(0.20)-LDH/CC electrocatalyst demonstrates a low overpotential of only 226 mV and high stability at a current density of 10 mA·cm^(−2),which is superior to most LDH-based OER catalysts reported previously.Furthermore,it only required 1.611 V voltage to drive the overall water splitting device at the current density of 10 mA·cm^(−2).The present study represents a significant advancement in the development and applications of new OER catalysts.

Distinct immune escape and microenvironment between RG-like and pri-OPC-like glioma revealed by single-cell RNA-seq analysis

The association of neurogenesis and gliogenesis with glioma remains unclear.By conducting single-cell RNA-seq analyses on 26 gliomas,we reported their classification into primitive oligodendrocyte precursor cell(pri-OPC)-like and radial glia(RG)-like tumors and validated it in a public cohort and TCGA glioma.The RG-like tumors exhibited wild-type isocitrate dehydrogenase and tended to carry EGFR mutations,and the pri-OPC-like ones were prone to carrying TP53 mutations.Tumor subclones only in pri-OPC-like tumors showed substantially down-regulated MHC-I genes,suggesting their distinct immune evasion programs.Furthermore,the two subgroups appeared to extensively modulate glioma-infiltrating lymphocytes in distinct manners.Some specific genes not expressed in normal immune cells were found in glioma-infiltrating lymphocytes.For example,glial/glioma stem cell markers OLIG1/PTPRZ1 and B cell-specific receptors IGLC2/IGKC were expressed in pri-OPC-like and RG-like glioma-infiltrating lymphocytes,respectively.Their expression was positively correlated with those of immune checkpoint genes(e.g.,LGALS33)and poor survivals as validated by the increased expression of LGALS3 upon IGKC overexpression in Jurkat cells.This finding indicated a potential inhibitory role in tumor-infiltrating lymphocytes and could provide a new way of cancer immune evasion.

Revealing structural degradation in layered structure oxides cathode of lithium ion batteries via in-situ transmission electron microscopy

Transition metal oxides with layered structure have been widely used as cathode materials for lithium-ion batteries(LIBs)which have relatively high energy density,large capacity and long life.However,in the long-term electrochemical cycle,the inevitable degradation of performance of LIBs due to structural degradation in cathodes severely restricts their large-scale practical applications.Understanding the underlying mechanism of structural degradation is the most critical scientific problem.Recently,in situ transmission electron microscopy(TEM)has become a useful tool to study the structural and compositional evolutions at atomic scale in electrochemical reactions,which provided a unique and in-depth understanding of the structural degradation.In this review,we discuss the recent advances in the in situ TEM,focusing on its role in revealing the structural degradation mechanisms in the four key places:(1)the interface between the cathodes and electrolyte;(2)the cathode surface;(3)the particle interior and(4)those induced by thermal effect.The insight gained by the in-situ TEM which is still developing at its fast pace is unique and expected to provide guidance for designing better layered cathode materials.

将硅纳米颗粒限域在多壳层空心球:一种提升循环稳定性的有效策略

单质硅是一种有潜力的高容量锂离子电池负极材料.然而,受限于充放电过程中巨大的体积膨胀,其循环性能并不理想.在这个工作中,我们设计了一种独特的三组分复合负极材料(Si/Cr_(2)O_(3)/C),其中Si纳米颗粒被限域在碳包覆的氧化铬多层空心球(MSHSs)中.得益于Cr_(2)O_(3)/C基体的体积变化缓冲能力与优异的结构稳定性,将Si纳米颗粒封装在MSHSs中可以有效地提高其电化学性能.合理的结构设计赋予了Si/Cr_(2)O_(3)/C三组分复合材料高的可逆容量(在100 mA g^(-1)的电流密度下,比容量为1351 mA h g^(-1))和稳定的循环性能(在500 mA g^(-1)的电流密度下,循环300次后比容量保持在716 mA h g^(-1)).这一工作提出了一种多壳层空心结构设计的新思路,以解决硅基负极材料循环性差的瓶颈.

异价离子取代构建高离子电导率的插层结构

在纳米尺度通道内的离子传输是纳米流体学领域研究的重点.二维(2D)材料的本征层状结构为流体离子提供了稳健的纳米传输通道.为实现流体离子在2D材料薄膜内的高效传输,本文开发了一种新颖的异价离子取代插层策略,通过化学气相输运法直接合成多种具有高离子电导结构的单晶.将块体单晶置入水中通过手动摇晃即可获得二维纳米片分散液,组装后的薄膜展现出高的锂离子电导率,优于目前多数关于2D材料薄膜水相锂离子电导率的报道.这种在合成过程中直接构筑离子传输结构的策略与目前已有的先剥离2D材料后对纳米片修饰改性的方法完全不同.因此,这种普适性的异价离子取代插层策略将会为更多高离子电导率的2D材料薄膜的开发提供借鉴与参考.

界面工程实现Au@MoS_(2)核壳异质结在等离激元学和光电子学领域卓越的热载流子输运动力学

贵金属和二维半导体构建的异质结为等离激元纳米结构产生的热载流子提供了独特的电荷传输路径,有望应用于各种等离激元和光电子器件.然而,传统异质结构的电荷转移速度和效率通常受限于有限的界面面积和不可避免的界面污染.本文中,具有原子级清洁和较大接触界面的新型Au@MoS_(2)核壳异质结构能够实现超快和高效的热电子转移.飞秒瞬态吸收光谱研究表明,Au@MoS_(2)中从金纳米颗粒到MoS_(2)的热电子注入时间常数小于244 fs,而机械转移方法制备的Au/MoS_(2)对照样品的热电子注入时间常数为493 fs,同时,电荷转移效率从Au/MoS_(2)的3.33%提升至Au@MoS_(2)的25.3%.开尔文探针力显微镜和离散偶极近似研究进一步证明了上述结果,明显改善的电荷转移归因于原子级清洁和完全封装的异质结界面.这项研究提供了贵金属-二维半导体异质结构内固有电荷转移的基本理解,从而展现了Au@MoS_(2)这一新型异质结结构在等离激元和光电子器件中的应用前景.

Mini-temporal approach as an alternative to the classical pterional approach for resective temporal region surgeries

Background:Classical pterional appoach for temporal surgeries may cause atrophy and dysfunction of temporalis,injury to the facial nerve,and unnecessary cortical exposure.As an alternative to the classical pterional approach for such surgeries,we hereby describe an mini-temporal approach which reduces these risks and proven to be practical in neurological surgeries.Material and methods:In the mini-temporal incision design,the frontal end of the incision never surpassed the hairline at the level of temporal line,and a one-layer skin-galea-muscle flap was detached from the cranium,effectively avoiding the injuries of facial nerve.The surgical bone window was completely located underneath the temporalis muscle,allowing it to be completely repositioned postoperatively.Results:We demonstrated the application of mini-temporal approach in a variety of temporal region tumors,which can be applied to complete successful resective surgeries while effectively reducing injuries to extra-temporal cortex,temporalis,and facial nerve.There were no postoperative complications related to extra-temporal cortical damage,atrophy of temporalis,or injury to the facial nerve.Conclusion:The mini-temporal approach can effectively shorten the time of craniotomy and closure,decrease the size of bony removal,increase the restoration of temporalis during closure,and lower the chance of facial nerve injury.Therefore,it improves cosmetic outcomes and reduces the risk of unintentional extra-temporal cortical injury,which fully embodies the minimally invasive principle in neurosurgery.

BDGOA:A bot detection approach for GitHub OAuth Apps

As various software bots are widely used in open source software repositories,some drawbacks are coming to light,such as giving newcomers non-positive feedback and misleading empirical studies of software engineering researchers.Several techniques have been proposed by researchers to perform bot detection,but most of them are limited to identifying bots performing specific activities,let alone distinguishing between GitHub App and OAuth App.In this paper,we propose a bot detection technique for OAuth App,named BDGOA.24 features are used in BDGOA,which can be divided into three dimensions:account information,account activity,and text similarity.To better explore the behavioral features,we define a fine-grained classification of behavioral events and introduce self-similarity to quantify the repeatability of behavioral sequence.We leverage five machine learning classifiers on the benchmark dataset to conduct bot detection,and finally choose random forest as the classifier,which achieves the highest F1-score of 95.83%.The experimental results comparing with the state-of-the-art approaches also demonstrate the superiority of BDGOA.

Multi-resolution network based image steganalysis model

Recently, many steganalysis approaches improve their feature extraction ability through addingconvolutional layers. However, it often leads to a decrease of resolution in the feature map during downsampling,which makes it challenging to extract weak steganographic signals accurately. To address this issue, this paperproposes a multi-resolution steganalysis net (MRS-Net). MRS-Net adopts a multi-resolution network to extract globalimage information, fusing the output feature map to ensure high-dimensional semantic information andsupplementing low-level detail information. Furthermore, the model incorporates an attention module which cananalyze image sensitivity based on different channel and spatial information, thus effectively focusing on areas withrich steganographic signals. Multiple benchmark experiments on the BOSSBase 1.01 dataset demonstrate that theaccuracy of MRS-Net significantly improves by 9.9% and 3.3% compared with YeNet and SRNet, respectively,demonstrating its exceptional steganalysis capability.

Narboh D, a Respiratory Burst Oxidase Homolog in Nicotiana attenuata, is Required for Late Defense Responses After Herbivore Attack

The superoxide (O2-)-generating NADPH oxidases are crucial for the defense of plants against attack from pathogens; however, it remains unknown whether they also mediate responses against chewing insect herbivores. The transcripts of the respiratory burst NADPH oxidase homolog Narboh D in Nicotiana attenuate are rapidly and transiently elicited by wounding, and are amplified when Manduca sexta oral secretions (OS) are added to the wounds. The fatty-acid-amino-acid-conjugates (FACs), demonstrably the major elicitors in M. sexta OS, are responsible for the increase in Narboh D transcripts. Silencing Narboh D significantly reduced reactive oxygen species (ROS) levels after OS elicitation, but neither OS-elicited jasmonic acid (JA) or JA-isoleucine (JA-Ile) bursts, pivotal hormones that regulates plant resistance to herbivores, nor early transcripts of herbivore defense-related genes (NaJAR4 and NaPAL1), were influenced. However, late OS-elicited increases in trypsin proteinase inhibitors (TPIs), as well as the transcript levels of defense genes such as polyphenol oxidase, TPI and Thionin were significantly reduced. In addition, Narboh D-silenced plants were more vulnerable to insect herbivores, especially the larvae of the generalist Spodoptera littoralis. We thus conclude that Narboh D-based defenses play an important role in late herbivore-elicited responses.