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The epitaxial growth of dendrites, which often results in a strong texture, is the most common phenomenon during the laser additive manufacturing process. In this study, the epitaxial growth of dendrites and texture evolution in three directions were studied by changing the z-increment, pulse period, and track offset, respectively. The influence of the molten pool interface on the growth and competition of dendrites is analyzed. Both green grains ( // BD) with rotated cube texture in the molten pool overlapping zones and red grains ( // BD) with fiber texture in the molten pool center zones coexist for different z-increment samples, forming the typical sandwich texture feature. In a short pulse period, the dendrites can grow directly epitaxially and form the strong fiber texture due to gentle interface and short distance. With the decrease of the track offset, the molten pool morphology changes from flat to narrow and deep. When θ is close to 90°, dendrites grow along the secondary dendrite arms at the overlapping zone, forming V-shape grains. This work also provides a promising method for texture customization for laser additive manufacturing.

Thyroid hormone (TH) plays important roles in the developing brain. TH deficiency in early life leads to severe developmental impairment in the hippocampus. However, the mechanisms of TH action in the developing hippocampus are still largely unknown. In this study, we generated 3,5,3’-tri-iodo-l-thyronine (T3)-free neuronal supplement, based on the composition of neuronal supplement 21 (NS21), to examine the effect of TH in the developing hippocampus using primary cultured neurons. Effects of TH on neurons were compared between cultures in this T3-free culture medium (-T3 group) and a medium in which T3 was added (+T3 group). Morphometric analysis and RT-qPCR were performed on 7, 10, and 14 days in vitro (DIV). On 10 DIV, a decreased dendrite arborization in -T3 group was observed. Such difference was not observed on 7 and 14 DIV. Brain-derived neurotrophic factor (Bdnf) mRNA levels also decreased significantly in -T3 group on 10 DIV. We then confirmed protein levels of phosphorylated neurotrophic tyrosine kinase type 2 (NTRK2, TRKB), which is a receptor for BDNF, on 10 DIV by immunocytochemistry and Western blot analysis. Phosphorylated NTRK2 levels significantly decreased in -T3 group compared to +T3 group on 10 DIV. Considering the role of BDNF on neurodevelopment, we examined its involvement by adding BDNF on 8 and 9 DIV. Addition of 10 ng/ml BDNF recovered the suppressed dendrite arborization induced by T3 deficiency on 10 DIV. We show that the lack of TH induces a developmental delay in primary hippocampal neurons, likely caused through a decreased Bdnf expression. Thus, BDNF may play a role in TH-regulated dendritogenesis.

Solidification process is a complex phase transition problem involving multiscale and multiphysical characteristics. To investigate the complex interaction, a high‐performance numerical scheme is developed to explore the thermal‐solute‐convection interaction during solidification. Al–Cu dendrite growth with the Lewis number ≈104 and Prandtl number ≈10−2 (or Schmidt number ≈102) is simulated and discussed. By constructing a multilevel data structure, this numerical scheme allows the time step magnified by 2–3 orders of magnitude in comparison with that for explicit methods. With the capacity of the acceleration strategy including parallel computing and adaptive mesh refinement, the computing efficiency can be further improved by 2–3 orders of magnitude. The combination of multilevel structure and acceleration strategy makes a problem of up to 109 uniform meshes much easier to handle. The coupled governing equations involving the multiscale and multiphysical characteristics are solved with high efficiency and high numerical stability, even when the solid fraction approaches 100%. Both single and multi‐dendrite growths are discussed to reveal the effect of the thermal‐solute‐convection interaction on the large‐scale 2D and 3D microstructure evolution. The presence of the liquid flow changes the distribution of both domain temperature and solute component, which changes dendrite morphology and growth dynamics. [ABSTRACT FROM AUTHOR]

Thyroid hormone (TH) plays important roles in the developing brain. TH deficiency in early life leads to severe developmental impairment in the hippocampus. However, the mechanisms of TH action in the developing hippocampus are still largely unknown. In this study, we generated 3,5,3'-tri-iodo-l-thyronine (T3)-free neuronal supplement, based on the composition of neuronal supplement 21 (NS21), to examine the effect of TH in the developing hippocampus using primary cultured neurons. Effects of TH on neurons were compared between cultures in this T3-free culture medium (-T3 group) and a medium in which T3 was added (+T3 group). Morphometric analysis and RT-qPCR were performed on 7, 10, and 14 days in vitro (DIV). On 10 DIV, a decreased dendrite arborization in -T3 group was observed. Such difference was not observed on 7 and 14 DIV. Brain-derived neurotrophic factor (Bdnf) mRNA levels also decreased significantly in -T3 group on 10 DIV. We then confirmed protein levels of phosphorylated neurotrophic tyrosine kinase type 2 (NTRK2, TRKB), which is a receptor for BDNF, on 10 DIV by immunocytochemistry and Western blot analysis. Phosphorylated NTRK2 levels significantly decreased in -T3 group compared to +T3 group on 10 DIV. Considering the role of BDNF on neurodevelopment, we examined its involvement by adding BDNF on 8 and 9 DIV. Addition of 10 ng/ml BDNF recovered the suppressed dendrite arborization induced by T3 deficiency on 10 DIV. We show that the lack of TH induces a developmental delay in primary hippocampal neurons, likely caused through a decreased Bdnf expression. Thus, BDNF may play a role in TH-regulated dendritogenesis. [ABSTRACT FROM AUTHOR]

Class I ventral posterior dendritic arborisation (c1vpda) proprioceptive sensory neurons respond to contractions in the Drosophila larval body wall during crawling. Their dendritic branches run along the direction of contraction, possibly a functional requirement to maximise membrane curvature during crawling contractions. Although the molecular machinery of dendritic patterning in c1vpda has been extensively studied, the process leading to the precise elaboration of their comb-like shapes remains elusive. Here, to link dendrite shape with its proprioceptive role, we performed long-term, non-invasive, in vivo time-lapse imaging of c1vpda embryonic and larval morphogenesis to reveal a sequence of differentiation stages. We combined computer models and dendritic branch dynamics tracking to propose that distinct sequential phases of stochastic growth and retraction achieve efficient dendritic trees both in terms of wire and function. Our study shows how dendrite growth balances structure–function requirements, shedding new light on general principles of self-organisation in functionally specialised dendrites.

Condensation frosting is a type of icing encountered ubiquitously in our daily lives. Understanding the dynamics of condensation frosting is essential in developing effective technologies to suppress frost accretions that compromise heat transfer and system integrity. Here, we present an experimental study on ice dendrite growth atop a single frozen drop, an important step affecting the subsequent frosting process, and the properties of fully-developed frost layers. We evaluate the effect of natural convection by comparing the growth dynamics of ice dendrites on the surface of a frozen drop with three different orientations with respect to gravity. The results show that both the average deposition rate and its spatial variations are profoundly altered by surface orientations. Such behavior is confirmed by a numerical simulation, showing how gravity-assisted (hindered) vapor diffusion yields the deposition outcomes. These findings benefit the optimization of anti-/de- frosting technologies and the rational design of heat exchangers.

The zinc dendrite growth generally relies upon a "positive-feedback" mode, where the fast-grown tips receive higher current densities and ion fluxes. In this study, a self-limiting polyacrylamide (PAM) hydrogel that presents negative feedback to dendrite growth is developed. The monomers are purposefully polymerized at the dendrite tips, then the hydrogel reduces the local current density and ion flux by limiting zinc ion diffusion with abundant functional groups. As a consequence, the accumulation at the dendrite tips is restricted, and the (002) facets-oriented deposition is achieved. Moreover, the refined porous structure of the gel enhances Coulombic Efficiency by reducing water activity. Due to the synergistic effects, the zinc anodes perform an ultralong lifetime of 5100 h at 0.5 mA cm -2 and 1500 h at 5 mA cm -2 , which are among the best records for PAM-based gel electrolytes. Further, the hydrogel significantly prolongs the lifespan of zinc-ion batteries and capacitors by dozens of times. The developed in situ hydrogel presents a feasible and cost-effective way to commercialize zinc anodes and provides inspiration for future research on dendrite suppression using the negative-feedback mechanism., (© 2023 Wiley‐VCH GmbH.)

Aqueous zinc-ion batteries (AZIBs) have gained significant attentions for their inherent safety and cost-effectiveness. However, challenges, such as dendrite growth and anodic corrosion at the Zn anode, hinder their commercial viability. In this paper, an organic-inorganic coating layer (Nafion-TiO 2 ) was introduced to protect the Zn anode and electrolyte interface. Briefly, Nafion effectively shields against the corrosion from water molecules through the hydrophobic wall of -CF 3 and guided zinc deposition from the -SO 3 functional group, while TiO 2 particles with a higher Young's modulus (151 GPa vs 120 GPa from Zn metal) suppress the zinc dendrite formation. As a result, with the protection of Nafion-TiO 2, the symmetrical Zn∥Zn battery shows an improved cycle life of 1,750 h at 0.5 mA cm -2 , and the full cell based on Zn∥MnO 2 shows a long cycle life over 1,500 cycles at 1 A g -1 . Our research offers a novel approach for protecting zinc metal anodes, potentially applicable to other metal anodes such as those in lithium and sodium batteries.

Members of the Wnt family of secreted signaling proteins influence many aspects of neural development and function. Wnts are required from neural induction and axis formation to axon guidance and synapse development, and even help modulate synapse activity. Wnt proteins activate a variety of downstream signaling pathways and can induce a similar variety of cellular responses, including gene transcription changes and cytoskeletal rearrangements. This review provides an introduction to Wnt signaling pathways and discusses current research on their roles in vertebrate neural development and function.

During prolonged nutrient restriction, developing animals redistribute vital nutrients to favor brain growth at the expense of other organs. In Drosophila, such brain sparing relies on a glia-derived growth factor to sustain proliferation of neural stem cells. However, whether other aspects of neural development are also spared under nutrient restriction is unknown. Here we show that dynamically growing somatosensory neurons in the Drosophila peripheral nervous system exhibit organ sparing at the level of arbor growth: Under nutrient stress, sensory dendrites preferentially grow as compared to neighboring non-neural tissues, resulting in dendrite overgrowth. These neurons express lower levels of the stress sensor FoxO than neighboring epidermal cells, and hence exhibit no marked induction of autophagy and a milder suppression of Tor signaling under nutrient stress. Preferential dendrite growth allows for heightened animal responses to sensory stimuli, indicative of a potential survival advantage under environmental challenges.

One of the root causes of lithium battery failure is lithium dendrite formation. Dendrites can result in internal short circuits and ultimately thermal runaway, fires, and explosions. Unfortunately, it has been difficult to study dendrites due to an inability to conduct in-situ observations. This paper presents an in-situ observation approach, consisting of an optically transparent lithium battery cell to observe dendrite growth evolution while concurrently monitoring the electrical characteristics of the cell under various current densities.

Rechargeable sodium batteries are a promising technology for low‐cost energy storage. However, the undesirable drawbacks originating from the use of glass fiber membrane separators have long been overlooked. A versatile grafting–filtering strategy was developed to controllably tune commercial polyolefin separators for sodium batteries. The as‐developed Janus separators contain a single–ion‐conducting polymer‐grafted side and a functional low‐dimensional material coated side. When employed in room‐temperature sodium–sulfur batteries, the poly(1‐[3‐(methacryloyloxy)propylsulfonyl]‐1‐(trifluoromethanesulfonyl)imide sodium)‐grafted side effectively enhances the electrolyte wettability, and inhibits polysulfide diffusion and sodium dendrite growth. Moreover, a titanium‐deficient nitrogen‐containing MXene‐coated side electrocatalytically improved the polysulfide conversion kinetics. The as‐developed batteries demonstrate high capacity and extended cycling life with lean electrolyte loading. [ABSTRACT FROM AUTHOR]

Zn−Ni secondary battery is a promising candidate as next generation of energy storage battery. However, suffering from the poor cycle performance, its commercialization remains rather challenging. The severe dendrite growth of Zn anode and the rapid capacity decay caused by its uncontrollable dissolution and poor electronic conductivity of ZnO are the main factors. Herein, we report a novel Indium (In) doped ZnO/rGO anode material to inhibit ZnO dissolution through the generated C−O−Zn bond between ZnO and graphene. Meanwhile, the capacity decay decline due to the enhanced electronic conductivity of ZnO by the In doping and combination of graphene. As a result, In doped ZnO/rGO anode material delivers a high specific capacity of 643.4 mAh g−1 (coulombic efficiency 97.63 %) and remains 531.3 mAh g−1 after 125 cycles at 0.5 C, which are significantly higher than bare ZnO. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (AZIBs) have attracted increasing attention as a next‐generation energy storage system because of their inherent safety, high capacity, and cost effectiveness. However, the poor cycling durability and low coulombic efficiency of zinc anodes substantially restrict their further development, which should be attributed to the severe dendrite growth, shape change, surface passivation, self‐corrosion, and byproduct formation across the repeated plating/stripping processes. To address these critical issues, great efforts have been dedicated to the rational design of zinc anodes. In this review, different strategies for the performance improvement of zinc anodes are summarized as well as recent research that boosts their development. These methods include the surface modification, novel host‐anode development for zinc, electrolyte formulation, and separator design. Their respective advantages and defects are compared and discussed in detail. The challenges and further prospects in this field are also addressed. This work is designed to shed light on advanced zinc anode constructions for high‐performance AZIBs assembly. [ABSTRACT FROM AUTHOR]

In lithium metal batteries, electrolytes containing a high concentration of salts have demonstrated promising cyclability, but their practicality with respect to the cost of materials is yet to be proved. Here we report a fluorinated aromatic compound, namely 1,2‐difluorobenzene, for use as a diluent solvent in the electrolyte to realize the "high‐concentration effect". The low energy level of the lowest unoccupied molecular orbital (LUMO), weak binding affinity for lithium ions, and high fluorine‐donating power of 1,2‐difluorobenzene jointly give rise to the high‐concentration effect at a bulk salt concentration near 2 m, while modifying the composition of the solid‐electrolyte‐interphase (SEI) layer to be rich in lithium fluoride (LiF). The employment of triple salts to prevent corrosion of the aluminum current collector further improves cycling performance. This study offers a design principle for achieving a local high‐concentration effect with reasonably low bulk concentrations of salts. [ABSTRACT FROM AUTHOR]

The deployment of high‐energy‐density lithium‐metal batteries has been greatly impeded by Li dendrite growth and safety concerns originating from flammable liquid electrolytes. Herein, we report a stable quasi‐solid‐state Li metal battery with a deep eutectic solvent (DES)‐based self‐healing polymer (DSP) electrolyte. This electrolyte was fabricated in a facile manner by in situ copolymerization of 2‐(3‐(6‐methyl‐4‐oxo‐1,4‐dihydropyrimidin‐2‐yl)ureido)ethyl methacrylate (UPyMA) and pentaerythritol tetraacrylate (PETEA) monomers in a DES‐based electrolyte containing fluoroethylene carbonate (FEC) as an additive. The well‐designed DSP electrolyte simultaneously possesses non‐flammability, high ionic conductivity and electrochemical stability, and dendrite‐free Li plating. When applied in Li metal batteries with a LiMn2O4 cathode, the DSP electrolyte effectively suppressed manganese dissolution from the cathode and enabled high‐capacity and a long lifespan at room and elevated temperatures. [ABSTRACT FROM AUTHOR]

Lithium metal has been regarded as one of the most promising anode materials for high-energy-density batteries due to its extremely high theoretical gravimetric capacity of 3860 mAh·g−1 along with its low electrochemical potential of − 3.04 V. Unfortunately, uncontrollable Li dendrite growth and repetitive destruction/formation of the solid electrolyte interphase layer lead to poor safety and low Coulombic efficiencies (CEs) for long-term utilization, which largely restricts the practical applications of lithium metal anode. In this review, we comprehensively summarized important progresses achieved to date in suppressing Li dendrite growth. Strategies for protection of Li metal anodes include designing porous structured hosts, fabricating artificial solid electrolyte interface (SEI) layers, introducing electrolyte additives, using solid-state electrolytes and applying external fields. The protection of Li metal anodes can be achieved by regulating the stripping and deposition behaviours of Li ions. Finally, the challenges remaining for lithium metal battery systems and future perspectives for Li metal anodes in practical applications are outlined, which are expected to shed light on future research in this field. [ABSTRACT FROM AUTHOR]

The thermosolutal convection can alter segregation pattern, change dendrite morphology and even cause freckles formation in alloy solidification. In this work, the multiphase-field model was coupled with lattice Boltzmann method to simulate the dendrite growth under melt convection in superalloy solidification. In the isothermal solidification simulations, zero and normal gravitational accelerations were applied to investigate the effects of gravity on the dendrite morphology and the magnitude of melt flow. The solute distribution of each alloy component along with the dendrite tip velocity during solidification was obtained, and the natural convection has been confirmed to affect the microsegregation pattern and the dendrite growth velocity. In the directional solidification simulations, two typical temperature gradients were applied, and the dendrite morphology and fluid velocity in the mushy zone during solidification were analyzed. It is found that the freckles will form when the average fluid velocity in the mushy zone exceeds the withdraw velocity. [ABSTRACT FROM AUTHOR]

Dendrite growth kinetics of Ni 3 Ti phase in Ni 75 Ti 25 and Ni 74 Ti 18 Al 8 alloys: (a-b) solid/liquid interface migration during recalescence; (c) dendritic growth velocity versus undercooling. • Rapid solidification of Ni 75 Ti 25 and Ni 74 Ti 18 Al 8 alloys are studied by ESL and LQ. • Dendritic growth velocities versus Δ T of Ni 3 Ti phase in two alloys are measured. • Ultrafine Ni 3 Ti dendrites in both alloys are obtained by LQ method. The rapid solidification mechanism of Ni 3 Ti intermetallic compound within undercooled Ni 75 Ti 25 and Ni 74 Ti 18 Al 8 alloys was investigated by electrostatic levitation(ESL) and liquid quenching(LQ) techniques. The dendritic growth velocity of Ni 3 Ti phase in these two alloys revealed power law relations versus liquid undercooling, whose maximum value was 138.9 mm s−1 for binary Ni 75 Ti 25 alloy at 255 K(0.15 T L) undercooling, while it was only 54.7 mm s−1 at 222 K(0.13 T L) undercooling for ternary Ni 74 Ti 18 Al 8 alloy. The crystalline structure of Ni 3 Ti phase in both alloys was characterized by fine dendrites under LQ state, whereas it displayed faceted growth mode under ESL condition. In addition, the Ni 3 Ti grains of Ni 75 Ti 25 alloy show a transition from incompletely to completely surrounded by the grain boundaries. [ABSTRACT FROM AUTHOR]

There is a potential danger of battery internal short-circuiting and shortened life span in zinc-nickel single flow batteries which is usually caused by the formation of dendritic crystals as a result of non-uniform electrodeposition. For the purpose of restraining dendrite growth and prolonging the battery service life, it is necessary to investigate the mechanism of dendrite growth that occurs on the surface of zinc anode. Here, a model for two-dimensional zinc dendrite growth is established by the phase field-lattice Boltzmann method (PF-LBM) to simulate how the morphology of zinc dendrites evolves as well as the corresponding distribution of the concentration field, potential field and flow field, and to analyze the influences of the applied voltage, electrolyte flow rate, anisotropy strength and exchange current density on dendrite growth. As the results show, higher exchange current density and applied voltage can promote dendrite growth. By choosing a suitable anisotropic strength, it is possible to change the morphology of the dendrites and decrease the formation of dendrites. Enlarging the electrolyte flow rate may make the distribution of ion concentration more uniform, which can inhibit the dendrite growth as well as affect the morphology of dendrites. [ABSTRACT FROM AUTHOR]

Zinc-air batteries have garnered significant attention owing to their high energy density and substantial anode active substance storage. Despite their potential advantages, the application of zinc-air batteries has been hindered in various domains by rapid performance degradation and reduced service life caused by zinc dendrite growth during cycling. This study presents a method of alloying zinc anodes with rare earth metals, such as Ce and Yb, as well as alkaline earth metal Mg to mitigate the growth of zinc dendrites. This is achieved by altering the anisotropy modulus and intensity at the interface energy of the zinc anode. This approach was verified using a COMSOL phase-field model based on an experimental study. The findings demonstrate that the optimal suppression of zinc dendrite growth was achieved with the anisotropy modulus of 6 and the inhibition efficiency is 35%. Moreover, the degree of anisotropic intensity exhibited by the interfacial energy was inversely proportional to the inhibition of zinc dendrite growth. The most effective approach to inhibit dendrite growth involved using a zinc anode composition of 98% Zn–2% Mg and 93.5% Zn–6.5% Yb. The addition of Ce into the zinc anode was found to increase the anisotropy modulus of the anode interface energy, changing the direction and decreasing the height of zinc dendrite growth. Similarly, the addition of Yb to the zinc anode decreased the anisotropic intensity of the interface energy, thereby impeding the growth of the main stem dendrite. [Display omitted] • Adding Ce increased the IEA modulus of the zinc anode, altering dendrite growth direction and decreasing height. • Adding Yb decreased the IEA intensity of the zinc anode, hindering main stem dendrite growth. • Optimal dendrite suppression was achieved with an IEA modulus of 6, yielding a 35% inhibition efficiency. • There is an inverse relationship between the IEA intensity and the inhibition of zinc dendrite growth. [ABSTRACT FROM AUTHOR]

• A three-dimensional cellular automaton method coupled with Eulerian multiphase is employed to study the dendrite growth during directional solidification under steady magnetic field. • Asymmetric characteristics of dendrites are observed in the case under the steady magnetic field. Steady magnetic field has important effects on the evolution of dendrites with different preferred orientations. • The value of u → l ∇ c l in vicinity of solid-liquid interface is proposed to illustrate the evolution of dendritic morphology. A three-dimensional cellular automaton method coupled with Eulerian multiphase is developed to investigate the dendrite growth during directional solidification under a steady magnetic field. In this model, the heat and solute transports, dendrite growth, thermal and solutal buoyancy, Thermo-Electro-Magnetic force and induced Lorentz force are taken into account. The simulation results reveal that asymmetric characteristics of dendrites are observed during the directional solidification of Al-2.5wt%Cu alloy under a steady magnetic field because of the intense melt flow occurring in the vicinity of the solid-liquid interface. The simulated results show that the numerical boundary condition has significant influence on the formation of tilted interface due to the changing of melt flow. Meanwhile, dendrites with various of preferred orientation are set to investigate the melt flow on the evolution of dendritic morphology during the directional solidification under the steady magnetic field. Finally, a criterion of u → l ∇ c l in the vicinity of solid-liquid interface is proposed to illustrate the evolution mechanism of dendritic morphology under steady magnetic field, i.e. , the region with u → l ∇ c l >0 promoting the dendrites growth and u → l ∇ c l <0 suppressing the dendrites growth. [ABSTRACT FROM AUTHOR]

• Dendrite growth in EMS-LBW is studied using phase field method with CFD model. • Temperature gradient decrease leads to a longer growth time and more branches. • Solidification rate increase promotes the interfacial instability and growth rate. • Lorentz force generated due to Seebeck effect, leading to more branches. • The calculated average branch width in the stable stage consistent with SEM results. Electromagnetic stirring is known to promote material flow, reduce porosity, uniform elements distribution, and refine grain in laser beam welding (LBW), which enhances the applicability of LBW in various industries. In this study, a phase-field model of dendrite growth in AA5754 Al alloy electromagnetic stirring laser beam welding was established. The model considered the thermal electromagnetic Lorentz force resulting from the interaction between the electric field generated by the Seebeck effect and the magnetic field, as well as the temperature gradient and solidification rate of the solidification interface obtained from the computational fluid dynamics electromagnetic stirring LBW model. The variation rules of dendrite growth with different magnetic parameters and effects are analyzed. Comprehensively, the magnetic field promotes the solidification rate, thus promoting interfacial instability and a large magnetic flux density leads to a faster interface instability. The solidification rate as well as the temperature gradient affect the growth rate, and the accelerated growth caused by the solidification rate with a high frequency and a large magnetic flux density effectively inhibits the slow growth caused by the temperature gradient. The thermal electromagnetic Lorentz force is the main factor for the branch increment at low frequencies, while both thermal electromagnetic Lorentz force and temperature gradient increase the number of branches at high frequencies. The calculated average branch numbers considering various factors in the stable stage under different magnetic parameters were consistent with the results of the scanning electron microscope tests. [ABSTRACT FROM AUTHOR]

The rapid eutectic growth of refractory liquid Re 72.5 W 27.5 alloy was realized under electrostatic levitation state, which attained a maximum undercooling of 510 K (0.16 T E). The active modulation of competitive nucleation was achieved by triggered nucleation and spontaneous nucleation respectively. For triggered nucleation between 107 and 454 K undercooling, anomalous eutectic grew primarily from the liquid alloy in the first recalescence, which was followed by lamellar eutectic growth epitaxially in the second recalescence. However, for spontaneous nucleation in the undercooling range of 366–510 K, σ dendrite became the primary phase in the first recalescence. The solidification mode of remaining liquid varied from lamellar eutectic to only (Re) phase as alloy undercooling increased beyond the critical value of 426 K. Once liquid undercooling exceeded 474 K, only σ phase prevailed in the whole solidifying process. It was found that the growth velocities for anomalous eutectic and σ dendrite both displayed power laws versus liquid undercooling. But anomalous eutectic exhibited a faster growth kinetics than σ dendrite in their coexistent undercooling regime of 366–454 K. Furthermore, the Vickers hardness decreased with undercooling in the case of triggered nucleation, whereas it increased for spontaneous nucleation because the harder σ dendrite had larger volume fraction with enhanced undercooling. The maximum Vickers hardness attained 1679 HV corresponding to the highest undercooling. • Ultra-refractory Re 72.5 W 27.5 alloy was rapidly solidified with the electrostatic levitation technique by triggered nucleation and spontaneous nucleation repectively. • For triggered nucleation, the liquid alloy would solidify with two recalescences, which corresponds to anomalous eutectic and lamellar eutectic growth respectively. • Under spontaneous nucleation, intermetallic σ dendrites would preferentially grow in the first recalescence. • The anamolous eutectic exhibited a faster growth kinetics than σ dendrite in their coexistent undercooling range of 366 and 454 K. [ABSTRACT FROM AUTHOR]

• A multi-scale cellular automaton-Eulerian multiphase model is employed to predict the microstructure during the laser directed energy deposition of Inconel 718. • The evolution of grain structure and dendritic structure during the solidification of the whole melt pool is realized. • A complex microstructure evolution mechanism including the epitaxial growth of dendrites from the substrate, heterogeneous nucleation, competitive growth between epitaxial columnar grains, nucleated columnar grains and equiaxed grains was presented. A multi-scale cellular automaton-Eulerian multiphase model is employed to predict the dendritic and grain structure during the laser directed energy deposition of Inconel 718. Simulated transient temperature histories form the macro-scale Eulerian multiphase model are used as input data to the micro-scale microstructure simulation. A complex microstructure evolution mechanism including the epitaxial growth of dendrites from the substrate, heterogeneous nucleation, competitive growth between epitaxial columnar grains, nucleated columnar grains and equiaxed grains was presented, and the influence of the transient thermal history on the primary dendrite arm spacing is discussed. By comparing the simulated solidification microstructure of the melt pool with the experimental results, the accuracy of the coupled model was verified. The results show a reduction in the primary dendrite arm spacing from 12.8μm to 8.3μm from the bottom to the top of the melt pool. According to the aspect ratio of the grains in the melt pool, the top area has 40% equiaxed grains and 60% columnar grains, while the bottom area has 8% equiaxed grains and 92% columnar grains. [ABSTRACT FROM AUTHOR]

[Display omitted] • The ZnSe protective layer is constructed on porous ZnO by hydrothermal method. • ZnO@ZnSe has a unique layered porous structure and an outstanding specific surface area. • ZnO@ZnSe electrodes can achieve long-term cycling stability at high rates. • ZnO@ZnSe still has a specific capacity of 577.5 mAh·g−1 after 1460 cycles. Zinc anodes suffer from self-corrosion, deformation and dendrite growth, which greatly limit the commercial application of zinc-nickel batteries. For this purpose, zinc oxide microspheres with porous surfaces are synthesized by a simple hydrothermal method, and ZnSe protective layer is constructed on their surfaces. The uniform coverage of ZnSe improves the corrosion resistance of the anode material and alleviates the polarization phenomenon during the cycle, thus ensuring the stability of the electrode material. Moreover, the prominent specific surface area optimizes the interface contact between anode and electrolyte, improving the ion transport efficiency while homogenizing the current distribution around the interface. Therefore, the discharge specific capacity of ZnO@ZnSe electrode can still reach 577.5 mAh·g−1 after 1460 cycles at a high rate. There is almost no attenuation compared with the initial discharge capacity, demonstrating an extremely excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

• CGO and Na 5 YSi 4 O 12 mix conductor layer (MCL) interface is constructed. • Interface oxygen potential regulation strategy is first applied to solid sodium ion batteries. • The MCL layer can effectively reduce interface electronic conductivity. • The modified battery exhibits excellent electrochemical performance at room temperatures. Solid sodium ion batteries (SSIBs) is the potential development direction of the next generation of energy storage technology owing to their low cost and superior safety. However, a series of problems such as high interfacial resistance and dendrites growth during the cycling process seriously hinder its practical application. Herein, a novel stable composite interface consisting of Ce 0.8 Gd 0.2 O 1.9 (CGO) and Na 5 YSi 4 O 12 (NYS) was constructed by a facile screen-printing method. The CGO with high oxygen fugacity can conduct oxygen ions to fill the oxygen vacancies due to interfacial reactions, homogenize the electric-field distribution, and impede electron conduction, thus inhibiting interfacial side reactions and dendrite growth. Therefore, the Na/NYS/Na symmetric battery can cycle stably for 3000 h at 0.1 mA cm−2 without short circuit and the NVP/NYS/Na full cell also exhibits a good electrochemical performance. This work makes an important contribution to the future development of safe and stable solid-state sodium battery systems. [ABSTRACT FROM AUTHOR]

Mutations in the Golgi SNARE (SNAP [soluble NSF attachment protein] receptor) protein Membrin (encoded by the GOSR2 gene) cause progressive myoclonus epilepsy (PME). Membrin is a ubiquitous and essential protein mediating ER-to-Golgi membrane fusion. Thus, it is unclear how mutations in Membrin result in a disorder restricted to the nervous system. Here, we use a multi-layered strategy to elucidate the consequences of Membrin mutations from protein to neuron. We show that the pathogenic mutations cause partial reductions in SNARE-mediated membrane fusion. Importantly, these alterations were sufficient to profoundly impair dendritic growth in Drosophila models of GOSR2-PME. Furthermore, we show that Membrin mutations cause fragmentation of the presynaptic cytoskeleton coupled with transsynaptic instability and hyperactive neurotransmission. Our study highlights how dendritic growth is vulnerable even to subtle secretory pathway deficits, uncovers a role for Membrin in synaptic function, and provides a comprehensive explanatory basis for genotype-phenotype relationships in GOSR2-PME.

The development of neural connectivity is essential for brain function, and disruption of this process is associated with autism spectrum disorders (ASDs). DIX domain containing 1 (DIXDC1) has previously been implicated in neurodevelopmental disorders, but its role in postnatal brain function remains unknown. Using a knockout mouse model, we determined that DIXDC1 is a regulator of excitatory neuron dendrite development and synapse function in the cortex. We discovered that MARK1, previously linked to ASDs, phosphorylates DIXDC1 to regulate dendrite and spine development through modulation of the cytoskeletal network in an isoform-specific manner. Finally, rare missense variants in DIXDC1 were identified in ASD patient cohorts via genetic sequencing. Interestingly, the variants inhibit DIXDC1 isoform 1 phosphorylation, causing impairment to dendrite and spine growth. These data reveal that DIXDC1 is a regulator of cortical dendrite and synaptic development and provide mechanistic insight into morphological defects associated with neurodevelopmental disorders.

Dendritic growth and branching are highly regulated processes and are essential for establishing proper neuronal connectivity. There is a critical phase of early dendrite development when these are heavily regulated by external cues such as trophic factors. Brain-derived neurotrophic factor (BDNF) is a major trophic factor known to enhance dendrite growth in cortical neurons, but the molecular underpinnings of this response are not completely understood. We have identified that BDNF induced translational regulation is an important mechanism governing dendrite development in cultured rat cortical neurons. We show that BDNF treatment for 1 h in young neurons leads to translational up-regulation of an important actin regulatory protein LIM domain kinase 1 (Limk1), increasing its level locally in the dendrites. Limk1 is a member of serine/threonine (Ser/Thr) family kinases downstream of the Rho-GTPase pathway. BDNF induced increase in Limk1 levels leads to increased phosphorylation of its target protein cofilin1. We observed that these changes are maintained for long durations of up to 48 h and are mediating increase in number of primary dendrites and total dendrite length. Thus, we show that BDNF induced protein synthesis leads to fine-tuning of the actin cytoskeletal reassembly and thereby mediate dendrite development.

The control of the solidification structure of a casting billet is directly correlated with the quality of steel. Variations in superheat can influence the transition from columnar crystals to equiaxed crystals during the solidification process, subsequently impacting the final solidification structure of the billet. In this study, a model of microstructure evolution during billet solidification was established by combining simulation and experiment, and the dendrite growth microstructure evolution during billet solidification under different superheat was studied. The results show that when the superheat is 60 K, the complete solidification time of the casting billet from the end of the 50 mm section is 252 s, when the superheat is 40 K, the complete solidification time of the casting billet is 250 s, and when the superheat is 20 K, the complete solidification time of the casting billet is 245 s. When the superheat is 20 K, the proportion of the equiaxed crystal region is higher-the highest value is 53.35%-and the average grain radius is 0.84556 mm. The proportion of the equiaxed crystal region decreases with the increase of superheat. When the superheat is 60 K, the proportion of the equiaxed crystal region is the lowest-the lowest value is 46.27%-and the average grain radius is 1.07653 mm. Proper reduction of superheat can obviously reduce the size of equiaxed crystal, expand the area of equiaxed crystal and improve the quality of casting billet.

Aqueous zinc-ion batteries (AZIBs) have caused significant research attention due to their low redox potential of 0.76 V, high theoretical capacity of 820 mAh g -1 . However, the dendrite growth of zinc anode and the side reactions caused by water seriously affect the cycle life of AZIBs. To solve the above problems, a new method of etching zinc anodes with CuCl 2 salt solution was designed, which the zinc anode was named CZn. The process resulted to a uniformly distributed micro gully morphology on the zinc surface, and providing an increased number of nucleation sites for zinc deposition and reducing local current density. The calculation results of exchange current density and activation energy show that CZn has stronger Zn/Zn 2+ kinetic effect. At a current density of 5 mA cm -2 and an area capacity of 5 mAh cm -2 , cycle life of the CZn symmetrical cell can reach 500 h, which is more than seven times that of the raw Zn symmetrical cell. This work proposes a simple method of zinc anode protection, which provides a new idea for zinc metal anode protection., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Zinc-bromine batteries (ZBBs) have recently gained significant attention as inexpensive and safer alternatives to potentially flammable lithium-ion batteries. Zn metal is relatively stable in aqueous electrolytes, making ZBBs safer and easier to handle. However, Zn metal anodes are still affected by several issues, including dendrite growth, Zn dissolution, and the crossover of Br species from cathodes to corrode anodes, resulting in self-discharge and fast performance fading. Similarly, Br 2 undergoes sluggish redox reactions on cathodes, which brings several issues such as poor reaction kinetics, the highly corrosive nature of Br species leading to corrosion of separators and poisoning of anodes, and the volatile nature of Br species causing increased internal pressures, etc. These issues are compounded in flowless ZBB configuration as no fresh electrolyte is available to provide extra/fresh reaction species. In this review, the factors controlling the performance of ZBBs in flow and flowless configurations are thoroughly reviewed, along with the status of ZBBs in the commercial sector. The review also summarizes various novel methodologies to mitigate these challenges and presents research areas for future studies. In summary, this review will offer a perspective on the historical evolution, recent advancements, and prospects of ZBBs., (© 2023 The Authors. Advanced Science published by Wiley-VCH GmbH.)

Lithium (Li) metal has garnered significant attention as the preferred anode for high-energy lithium metal batteries. However, safety concerns arising from the growth of Li dendrites have hindered the advancement of Li metal batteries. In this study, we first elucidate the impact of external pressure and internal stress on dendrite growth and dissolution behavior of Li metal batteries during continuous charging-discharging cycles, employing a developed electrochemomechanical phase-field model. A typical parameter is defined to calculate the amount of dead Li that affects the electrochemical performance of Li metal batteries during multiple cycles. The underlying mechanisms of dendrites observed from in situ experiments are explained through the developed phase-field model. After charging/discharging, dendrites with a treelike structure yield a greater amount of dead Li compared to those with a needlelike configuration. Increasing the pressure appropriately can effectively reduce the growth points of dendrites and suppress the Li dendrite growth. Excessive pressure not only induces dendritic fractures that lead to the formation of dead Li but also undermines the battery performance. The accumulated internal stress might threaten the structural stability of the Li metal, thereby influencing the evolution of the Li dendrite morphology. A reasonable strategy is proposed to strike a balance between external pressure and the growth and dissolution of Li dendrites. These findings offer valuable insights into the judicious application of pressure to mitigate the advancement of electroplating reactions.

Water-induced parasitic reactions and uncontrolled dendritic Zn growth are long-lasting tricky problems that severely hinder the development of aqueous zinc-metal batteries. Those notorious issues are closely related to electrolyte configuration and zinc-ion transport behavior. Herein, through constructing aligned dipoles induced electric-field on Zn surface, both the solvation structure and transport behavior of zinc-ions are fundamentally changed. The vertically ordered zinc-ion migration trajectory and gradually concentrated zinc-ion achieved inside the polarized electric-field remarkably eliminate water related side-reactions and Zn dendrites. Zn-metal under the polarized electric-field demonstrated significantly improve reversibility and a dendrite-free surface with strong (002) Zn deposition texturing. Zn||Zn symmetric cell delivers greatly prolonged lifespan up to 1400 h (17 times longer than that of the cell based on bare Zn) while the Zn||Cu half-cell demonstrate ultrahigh 99.9% coulombic efficiency. NH 4 V 4 O 10 ||Zn half-cell delivered exceptional-high 132 mAh g -1 capacity after ultralong 2000 cycles (≈100% capacity retention). In addition, MnO 2 ||Zn pouch-cell under aligned dipoles induced electric-field maintains 87.9% capacity retention after 150 cycles under practical condition of high MnO 2 mass loading (≈10 mg cm -2 ) and limited N/P ratio. It is considered that this new strategy can also be implemented to other metallic batteries and spur the development of batteries with long-lifespan and high-energy-density., (© 2023 Wiley-VCH GmbH.)

Difluoroethylene carbonate (DFEC) featuring abundant fluorine atoms has been proposed as a multifunctional electrolyte additive to boost the stability of the electrolyte-electrode interphase of lithium metal batteries. Thus, introducing the DFEC additive enables a high capacity retention rate of the Li||NCM811 full cell (up to 75% after 200 cycles) at 4.5 V high voltage.

Uncontrolled dendrite growth and water-related side reactions in mild electrolytes are the main causes of poor cycling stability of zinc anodes, resulting in the deterioration of aqueous zinc-based batteries. Herein, a multifunctional fluorapatite (Ca 5 (PO 4 ) 3 F) aerogel (FAG) interface layer is proposed to realize highly stable zinc anodes via the integrated regulation of Zn 2+ migration kinetics and Zn (002) orientation deposition. Owing to the well-defined aerogel nanochannels and the rich Zn 2+ adsorption sites resulting from the ion exchange between Ca 2+ and Zn 2+ , the FAG interface layer could significantly accelerate the Zn 2+ migration and effectively homogenize the Zn 2+ flux and nucleation sites, thus promoting rapid and uniform Zn 2+ migration at the electrode/electrolyte interface. Additionally, during the cycling process, the F atoms from FAG promote the in situ generation of ZnF 2 , which facilitates the manipulation of the preferred Zn (002) orientation deposition, thus efficiently suppressing dendrite growth and side reactions by combining with the above synergistic effects. Consequently, the FAG-modified Zn anode displays a stable cycle life of over 4000 h at 1 mA cm -2 and exhibits highly reversible Zn plating/stripping behavior. Meanwhile, the Zn||MnO 2 full cells exhibit improved cycle stability over 2000 cycles compared with that of the bare Zn, highlighting the virtues of the FAG protective layer for highly reversible Zn anodes. Our work brings the insight in to stabilize Zn anodes and power the commercial applications of aqueous zinc-based batteries.

Hypothesis: Aqueous zinc-ion batteries (AZIBs) have received considerable attention owing to their safety, low cost, and environmental benignity. However, the side reactions of hydrogen evolution revolution and Zn dendrite growth reduce the Coulombic efficiency and life span of AZIBs. To address these issues, we designed an artificial protective layer of a Te-hybridized core-shell zeolitic imidazolate framework (ZIF)., Experiments: A core-shell structure of ZIF-8@ZIF-67 was first developed as a protecting layer on the Zn anode. To improve the poor conductivity of ZIF and its affinity for Zn, the core-shell structure was hybridized with zincophilic Te to increase the surface area and reduce the charge-transfer resistance., Findings: By incorporating metallic Te into ZIF-8 and ZIF-67, the nucleation potential and charge-transfer resistance were significantly reduced, enhancing the ion reaction kinetics and electron migration. Benefiting from the Te-hybridized ZIF-8@ZIF-67-derived nitrogen-doped porous carbon (Te-hybridized ZIF-8@ZIF-67/NC) layer, a full cell of Zn coated with Te-hybridized ZIF-8@ZIF-67/NC//MnO 2 exhibited an excellent rate performance of 214 mAh g -1 at an ultrahigh current density of 10 A g -1 and ultralong cycle life (3200 cycles) without the formation of Zn dendrites., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

In order to study the basic principles of vibration-excited liquid metal nucleation technology, a coupled model to connect the temperature field calculated by ANSYS Fluent and the dendritic growth simulated by cellular automaton (CA) algorithm was proposed. A two-dimensional CA model for dendrite growth controlled by solute diffusion and local curvature effects with random zigzag capture rule was developed. The proposed model was applied to simulate the temporal evolution of solidification microstructures under different degrees of surface undercooling and vibration frequency of the crystal nucleus generator conditions. The simulation results showed that the predicted columnar dendrites regions were more developed, the ratio of interior equiaxed dendrite reduced and the size of dendrites increased with the increase of the surface undercooling degrees on the crystal nucleus generator. It was caused by a large temperature gradient formed in the melt. The columnar-to-equiaxed transition (CET) was promoted, and the refined grains and homogenized microstructure were also achieved at the high vibration frequency of the crystal nucleus generator. The influences of the different process parameters on the temperature gradient and cooling rates in the mushy zone were investigated in detail. A lower cooling intensity and a uniform temperature gradient distribution could promote nucleation and refine grains. The present research has guiding significance for the process parameter selection in the actual experimental.

Abstract The melt of a congruently melting CoSi non-stoichiometric intermetallic compound was undercooled and solidified spontaneously. The recalescence processes were recorded by a high speed camera to measure the growth velocities and the as-solidified microstructures were analyzed by electron back-scattering diffraction (EBSD) to show the grain refinement mechanisms. The monotonous increase of the growth velocity with undercooling indicates that the effect of disorder trapping is insignificant. The microstructure changes from coarse dendrites to refined equiaxed grains and then to coarse dendrites. Spontaneous grain refinement at low undercooling can be described well by both the dendrite fragmentation model and the chemical superheating model. The formation of coarse dendrites instead of refined equiaxed grains at high undercooling is ascribed to the considerable decrease of the dendrite remelting fraction. A transition from dendrites to dendritic seaweeds occurs at high undercooling. Regarding that the formation of dendritic seaweeds at high undercooling does not lead to spontaneous grain refinement, it cannot be the origin of grain refinement even in the case that dendritic seaweed splits is possible to assist the grain refinement process. The current work could be helpful for controlling the non-equilibrium microstructures and improving the mechanical properties of intermetallic compounds. Graphical abstract Image 1 Highlights • Growth velocities were measured for rapid solidification of the CoSi intermetallic compound. • As-solidified microstructures were analyzed by electron back-scattering diffraction. • A transition from dendrites to dendritic seaweeds was found at high undercooling. • Growth kinetics and grain refinement mechanisms were analyzed theoretically. [ABSTRACT FROM AUTHOR]

Dendritic growth and branching are highly regulated processes and are essential for establishing proper neuronal connectivity. There is a critical phase of early dendrite development when these are heavily regulated by external cues such as trophic factors. Brain-derived neurotrophic factor (BDNF) is a major trophic factor known to enhance dendrite growth in cortical neurons, but the molecular underpinnings of this response are not completely understood. We have identified that BDNF induced translational regulation is an important mechanism governing dendrite development in cultured rat cortical neurons. We show that BDNF treatment for 1 h in young neurons leads to translational up-regulation of an important actin regulatory protein LIM domain kinase 1 (Limk1), increasing its level locally in the dendrites. Limk1 is a member of serine/threonine (Ser/Thr) family kinases downstream of the Rho-GTPase pathway. BDNF induced increase in Limk1 levels leads to increased phosphorylation of its target protein cofilin1. We observed that these changes are maintained for long durations of up to 48 h and are mediating increase in number of primary dendrites and total dendrite length. Thus, we show that BDNF induced protein synthesis leads to fine-tuning of the actin cytoskeletal reassembly and thereby mediate dendrite development. [ABSTRACT FROM AUTHOR]

Abstract The effect of withdrawal rates on the dendrite growth and defects formation in the rejoined platforms of a Ni-based single crystal superalloy during directional solidification was studied by experimental investigations and ProCAST simulations. The results showed that the dendrite pattern in the rejoined platforms mainly comprised two regions: original primary dendrite region and lateral growth region. With increasing withdrawal rate, the lateral growth was more severe and the tendency of low angle grain boundaries (LABs) was greater because of dendrite deformation. Once the withdrawal rate exceeded 100 μm/s, local fragmentation appeared in the middle of the platforms and some ternary dendrites were detached from their parent dendrites. When the withdrawal rate was increased to 150 μm/s, lots of dendrite fragments formed and the integrity of single crystal was completely destroyed, which might be caused by the solute enrichment and was further promoted by the unstable growth conditions. Highlights • A model with rejoined platforms was designed, which was the sensitive site prone to casting defects. • Grain boundaries are easy to form in the rejoined platforms. • A new defect, fragmentation was discovered in the rejoined platforms and was reasonably explained. • The effect of withdrawal rates on the dendrite growth and defects formation in the rejoined platforms was investigated. [ABSTRACT FROM AUTHOR]