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While brain function is supported and constrained by the underlying structure, the connectome-based link estimated by current approaches is either relatively moderate or accompanied by high model complexity, with the essential principles underlying structure-function coupling remaining elusive. Here, by proposing a mapping method based on network eigendecomposition, we present a concise and strong correspondence between structure and function. We show that the explanation of functional connectivity can be significantly improved by incorporating interactions between different structural eigenmodes. We also demonstrate the pronounced advantage of the present mapping in capturing individual-specific information with simple implementation. Applying our methodology to the human lifespan, we find that functional diversity decreases with age, with functional interactions increasingly dominated by the leading functional mode. We also find that structure-function liberality weakens with age, which is driven by the decreases in functional components that are less constrained by anatomy, while the magnitude of structure-aligned components is preserved. Overall, our work enhances the understanding of structure-function coupling from a collective, connectome-oriented perspective and promotes a more refined identification of functional portions relevant to human aging, holding great potential for mechanistic insights into individual differences associated with cognition, development, and neurological disorders. An eigenmode-based structural and functional connectivity mapping approach applied to diffusion and functional MRI data reveals decreased structure-function liberality with age across the human lifespan. [ABSTRACT FROM AUTHOR]

Tomographic synthetic aperture radar (TomoSAR) obtains elevation resolution by adding multiple baselines successively in the direction perpendicular to the line of sight, thereby realizing three-dimensional (3D) reconstruction of complex scenes and significantly promoting the development of the 3D application field. However, a large data redundancy and long mapping time in traditional 3D imaging lead to a large data transmission burden, low efficiency, and high costs. To solve the above problems, this paper proposes a distributed SAR high-resolution and wide-swath (HRWS) 3D imaging technology scheme. The proposed scheme overcomes the size limitation of traditional single-satellite antennas through the multi-channel arrangement of multiple satellites in the elevation direction to achieve HRWS imaging; meanwhile, the distributed SAR system is integrated with tomographic processing technology to realize 3D imaging of difficult areas by using the elevation directional resolution of TomoSAR systems. HRWS 3D SAR increases the baseline length and channel number by transmission in turn, which leads to excessive pulse repetition frequency and causes echoes of different pulse signals to overlap in the same receiving cycle, resulting in range ambiguity and thus seriously affecting the quality of the 3D reconstruction. To solve this problem, this paper proposes a range ambiguity resolution algorithm based on multi-beam forming and verifies it on the measured data from airborne array SAR. Compared with the traditional TomoSAR, the distributed HRWS 3D SAR scheme proposed in this paper can obtain a greater mapping bandwidth with the same resolution in a single flight, thereby enhancing the time correlation, reducing data redundancy, and greatly improving mapping efficiency. [ABSTRACT FROM AUTHOR]

With the extensive application of titanium dioxide nanoparticles (TiO2 NPs), their impacts on calcium homeostasis have aroused extensive attention from scholars. However, there are still some controversies in relevant reports. Therefore, a systematic review was performed followed by a meta-analysis to explore whether TiO2 NPs could induce the imbalance in calcium homeostasis in vivo and in vitro through Revman5.4 and Stata15.0 in this research. Fourteen studies were included through detailed database retrieval and literature screening. Results indicated that the calcium levels were significantly increased and the activity of Ca2+-ATPase was significantly decreased by TiO2 NPs in vivo and in vitro. Subgroup analysis of the studies in vivo showed that TiO2 NPs exposure caused a significant increase in calcium levels in rats, exposure to large-sized TiO2 NPs (>10 nm) and long-term (>30 days) exposure could significantly increase calcium levels, and the activity of Ca2+-ATPase showed a concentration-dependent downward trend. Subgroup analysis of the studies in vitro revealed that intracellular calcium levels increased significantly in animal cells, exposure to small-sized TiO2 NPs (≤10 nm) and high concentration (>10 μg/mL) exposure could induce a significant increase in Ca2+ concentration, and the activity of Ca2+-ATPase also showed a concentration-dependent downward trend. This research showed that the physicochemical properties of TiO2 NPs and the experimental scheme could affect calcium homeostasis [ABSTRACT FROM AUTHOR]

Frequency stabilization is the premise of guaranteeing grid-friendly integration of virtual synchronous generator (VSG). Based on that premise, this article, focused on frequency stability, establishes the small signal model of grid-forming VSG system. At first, the mechanism of frequency oscillation occurring in system of active- and reactive-power coupling is analyzed by the defined feedback effect factor in this article. Besides, a new dynamic model is established for identifying dynamic interaction of voltage magnitudes and frequency by means of feedback effect. The analytical results of established models agree with that of eigenvalue analysis. Furthermore, a new virtual inductance control strategy is proposed to mitigate the unstable oscillation of frequency and powers, enhance damping performance, and improve stability margins. Unlike the conventional virtual inductance control, which is reliable on dual-loop control framework, the proposed virtual inductance control in this article is based on principle of energy conservation and can be applicable for the grid-forming inverter without inner dual-loop control structure. Finally, the proposed modeling as well as virtual inductance control method is experimentally verified. [ABSTRACT FROM AUTHOR]

[Display omitted] • Design and manufacture of Ni/MoO 2 catalysts with different morphologies, which confirm the effect of morphology engineering. • The excellent catalytic performance of H-Ni/MoO 2 benefits from a hollow porous spherical structure with amorphous carbon skeleton, compared with other morphological Ni/MoO 2. • The urea plays crucial role in porous hollow spherical morphology and carbon skeleton in the synthesized steps. • The urea-assistant synthesized way offers a simple and practical strategy to construct this structure for catalysts. The catalyst morphology has a strong impact on the activity of electrocatalytic hydrogen production. Considering the effect, we design and fabricate hollow spherical Ni/MoO 2 heterojunction. In addition, an amorphous carbon skeleton is inserted into the hollow sphere, which makes the structure more stable and porous. Compared with other morphological Ni/MoO 2 , the porous hollow spherical Ni/MoO 2 (H-Ni/MoO 2) with an internal carbon skeleton shows better hydrogen evolution reaction (HER) activity with a small overpotential of 58 mV to reach 10 mA cm−2 and a tafel value of 44.8 mV dec-1 in alkaline media. The developed HER performance of H-Ni/MoO 2 can be attributed to the larger active surface area of porous hollow spherical structure and the faster electron transfer and better stability of carbon skeleton. Undoubtedly, the urea plays a crucial role to construct the hollow spherical morphology and being decomposed to form holes and amorphous carbon in the synthesized steps. The soft-template strategy using urea as the addition for forming the porous hollow structure with carbon skeleton can be extended to explore superior non-noble metal for hydrogen production. [ABSTRACT FROM AUTHOR]

This letter proposes a generalized stabilizer-oriented design method for grid-forming virtual synchronous generator (GFVSG) attached to weak-stiffness power networks, where a rate of change of frequency feedforward control strategy (RoCoF-FCS) is put forward to improve frequency stability, enhance damping performance, and avoid aperiodic loss of synchronization (ALoS). In addition, the feedback analytical framework, which connects RoCoF and rate of change of voltage (RoCoV), is proposed to identify both wideband oscillation and ALoS. Finally, the proposed method is validated by time-domain simulations. [ABSTRACT FROM AUTHOR]

[Display omitted] Mitochondrial dysfunction has been implicated in the pathogenesis of Alzheimer's disease, a neurodegenerative disorder characterized by progressive cognitive decline. Voltage-dependent anion channel (VDAC), a protein located in the outer mitochondrial membrane, plays a critical role in regulating mitochondrial function and cellular energy metabolism. Recent studies have identified VDAC as a potential therapeutic target for Alzheimer's disease. This article aims to provide an overview of the role of VDAC in mitochondrial dysfunction, its association with Alzheimer's disease, and the potential of targeting VDAC for developing novel therapeutic interventions. Understanding the involvement of VDAC in Alzheimer's disease may pave the way for the development of effective treatments that can restore mitochondrial function and halt disease progression. [ABSTRACT FROM AUTHOR]

Virtual synchronous generator (VSG) has been a grid-friendly integration control technique for the integration of grid-connected inverters. However, the emulated inertia and damping of VSG control technique can also be used in the field of dc systems. In this article, a virtual synchronous control is proposed to dampen the wideband oscillation of dc voltage in a dc microgrid. The proposed control strategy contributes to maintaining the synchronous operation of dc converter with the network. Besides, the relationships among damping, inertia, wideband oscillation, rate of change of voltage (RoCoV) as well as DC voltage nadir (DCVN) are studied. It is concluded that the RoCoV and DCVN are similar as the oscillation frequency and fluctuation ranges of poorly-damped oscillation, respectively. A unified concept is proposed by connecting the oscillation-related stability with the inertial transient response originated from the imbalanced powers/mismatched currents. Besides this, the inertia plays the same role as damping because the inertia contributes to maintaining the original state and damping to impeding further change. A new feedback analytical method is proposed to clarify the important role of RoCoV and DCVN on the motion of dc voltage. Finally, the theoretical results are compared with simulations and experiments. [ABSTRACT FROM AUTHOR]

Virtual synchronous generator (VSG), recognized as a grid-friendly control technique, contributes to providing inertia and damping support from the grid-tied power electronic systems. However, similar to the conventional synchronous generator, the VSG is vulnerable to wideband oscillations and can even become unstable when the system is subjected to a variety of disturbances. To tackle this issue, this article proposes a magnitude-phase motion equation (MPME) for grid-forming VSG attached to a weak grid. Besides, a feedback analytical method is introduced to identify the frequency dynamic stability, judged by the sign of (dω/dt)/δω. Besides, the rate of change of frequency (RoCoF) and frequency nadir (FN) are evaluated by the two indices, i.e., dω/dt and δω. In addition, the relationship between the low-inertia-RoCoF-FN-related stability and the weak-damping-oscillation-related stability is illustrated by the feedback analysis. Moreover, in the framework of MPME, a reactive-power feedforward (RPFF) decoupling control strategy is proposed for the enhancement of stability and robustness performance of the VSG system. Finally, the proposed modeling and the RPFF decoupling control strategy are demonstrated with the experiments. [ABSTRACT FROM AUTHOR]

In mountainous basins with low anthropogenic influences, runoff generation varies geographically, and it is essential to investigate the hierarchical controls of geographical features on hydrological responses. In this study, a stepwise clustering scheme was proposed to classify 64 mountainous basins located in eastern China into 11 basin groups and 3 hierarchies according to the geographical features of rainfall, topography and geomorphology, and soil and geology. Then, the leave-one cross validation assessing the transferability of hydrological model parameters was used to measure the hydrological similarity among basins and within each group, and to examine the quality of classification. The results showed that 92% of all basins had other basins with high similarity. The overall similarity of the hydrological responses in the 11 basin groups was quite different. The basin groups driven by heavy rainfall events tended to form highly similar runoff processes. Basins in the groups with steeper terrain, more convergent slopes, rounder shapes, and better vegetation cover also exhibited a higher overall hydrological similarity. Then, according to the discharge characteristics, the controlling role and intensity of different hierarchical geographical features on hydrological responses were quantitatively represented. In 6 of the 11 basin groups, rainfall features (e.g. average monthly rainfall and rainstorm characteristics) were collectively the primary controlling factor of runoff, while topographic and geomorphic features were the second most important factor. Rainfall features were the second most important controlling factor in the other four basin groups. However, the controlling role of soil and geological features on hydrological responses appeared to be unstable. In summary, these findings could provide guidance for hydrological predictions in ungauged basins in diverse geographical environments. [ABSTRACT FROM AUTHOR]

Electrocatalytic water splitting is a useful and promising strategy to produce hydrogen, which is a sustainable and pollution‐free supply in the future. Herein, we design the FeOOH as an improved part to enhance the excellent water splitting catalytic activities of the Ni3S2, and the FeOOH−Ni3S2 shows remarkable electrocatalytic performance for OER and HER compared to the pristine Ni3S2 sample. Currently, we use a quick chemical immersion method to synthesize FeOOH on the surface of Ni3S2 nanosheets to form a FeOOH−Ni3S2 heterostructure. The FeOOH was formed as the dissolution process of Ni3S2 in Fe(NO3)3 solution. Our work opens up a quick, facile, and effective way to synthesize FeOOH and design high‐performance heterostructure electrocatalysts for energy conversion. [ABSTRACT FROM AUTHOR]

The complexity of fMRI signals quantifies temporal dynamics of spontaneous neural activity, which has been increasingly recognized as providing important insights into cognitive functions and psychiatric disorders. However, its heritability and structural underpinnings are not well understood. Here, we utilize multi-scale sample entropy to extract resting-state fMRI complexity in a large healthy adult sample from the Human Connectome Project. We show that fMRI complexity at multiple time scales is heritable in broad brain regions. Heritability estimates are modest and regionally variable. We relate fMRI complexity to brain structure including surface area, cortical myelination, cortical thickness, subcortical volumes, and total brain volume. We find that surface area is negatively correlated with fine-scale complexity and positively correlated with coarse-scale complexity in most cortical regions, especially the association cortex. Most of these correlations are related to common genetic and environmental effects. We also find positive correlations between cortical myelination and fMRI complexity at fine scales and negative correlations at coarse scales in the prefrontal cortex, lateral temporal lobe, precuneus, lateral parietal cortex, and cingulate cortex, with these correlations mainly attributed to common environmental effects. We detect few significant associations between fMRI complexity and cortical thickness. Despite the non-significant association with total brain volume, fMRI complexity exhibits significant correlations with subcortical volumes in the hippocampus, cerebellum, putamen, and pallidum at certain scales. Collectively, our work establishes the genetic basis and structural correlates of resting-state fMRI complexity across multiple scales, supporting its potential application as an endophenotype for psychiatric disorders. • fMRI complexity at multiple time scales is heritable across most brain regions. • fMRI complexity is related to surface area (SA) and cortical myelination (CM). • SA-complexity correlations mainly relate to common genetic and environmental effects. • CM-complexity correlations are primarily associated with environmental correlations. • fMRI complexity at certain scales relates to the volumes of some subcortical areas. [ABSTRACT FROM AUTHOR]

Tomographic synthetic aperture radar (TomoSAR) plays a critical role in the 3D reconstruction of complex urban targets with the capability of 3D imaging. Nevertheless, multipath scattering interference is common in 3D point clouds, seriously affecting the structure of the 3D model. In this letter, the multipath scattering phenomenon of buildings is analysed and the building 3D reconstruction of TomoSAR using multiple bounce scattering model is proposed. The superiority of the proposed method is demonstrated for experiments on array TomoSAR data. It is found that the proposed method not only achieves interference suppression but also improves integrity and accuracy taking advantage of multiple scattering information. [ABSTRACT FROM AUTHOR]

Doping engineering is considered an effective way to improve the electrocatalytic water splitting performance of catalysts. In this paper, P-doped Ni3S2/NF was prepared by Ar plasma-assisted chemical vapor deposition, where the P dopant was efficiently introduced into Ni3S2/NF under the assistance of Ar plasma. Meanwhile, numerous vacancies were generated due to plasma bombardment. In the doping process, the P dopants replace the S vacancies, which contributes to the strong bonding between the P dopants and Ni3S2. Due to the synergistic effect of the P dopants and S vacancies, the Sv-Ni3S2−xPx-4 catalyst has low HER and OER overpotentials of 89 mV and 216 mV at 10 mA cm−2, with a lower impedance value and good stability. The present work shows a facile route to introduce dopants and vacancies into catalyst materials for adding active sites, eventually improving their electrocatalytic performance. [ABSTRACT FROM AUTHOR]

The large-scale production and utilization of graphene oxide (GO) have raised concerns regarding its environmental exposure and potential risks. However, existing research on GO toxicity has primarily focused on individual organisms. Little attention has been given to the interaction between GO and the nitrogen-fixing symbiosis of legume-rhizobium. In this study, we focused on alfalfa (Medicago sativa L.), a typical leguminous nitrogen-fixing plant, to investigate the effects of GO on various aspects of this symbiotic relationship, including root nodulation, rhizobial viability, nodule nitrogen fixation, DNA damage, and the composition of the rhizobial community in the rhizosphere. As the dosage of GO increased, a significant inhibition in nodulation development was observed. Exposure to GO resulted in decreased growth and viability of rhizobia, as well as induced DNA damage in nodule cells. Furthermore, with increasing GO dosage, there were significant reductions in nitrogenase activity, leghemoglobin level, and cytoplasmic ammonia content within the root nodules. Additionally, the presence of GO led to notable changes in the rhizobial community in the rhizosphere. Our findings support the existence of the damage promoted by GO in the symbiosis of nitrogen fixing rhizobia with legumes. This underscores the importance of careful soil GO management. [Display omitted] • First study focused on the interaction between GO and the legume-rhizobium symbiosis. • GO impaired nodulation and nitrogen fixation and caused DNA damage in nodule cells. • A reduction in rhizobial growth and viability was observed following GO treatment. • GO altered the composition and diversity of the rhizobial community in the rhizosphere. [ABSTRACT FROM AUTHOR]

Molybdenum diselenide (MoSe 2) is a potential catalytic material for the electrocatalytic hydrogen evolution reaction (HER). However, due to the low density of its active sites, MoSe 2 nanosheets feature high overpotential in HER, which limits its practical application. This describes the method of doping the Ni in MoSe 2 nanosheets to increase active sites. The NiO 2 evenly dispersed on MoSe 2 by ethanol solution reduces to ~4 nm Ni nanoclusters under annealing process, which is firmly adhered to MoSe 2 nanosheets with Ni–Se bond. The electrochemical active surface area of Ni-doped MoSe 2 expands, proving that Ni dopants produce more activity sites in MoSe 2 nanosheets. The overpotential of MoSe 2 (at 10 mA cm−2) decreases from 335 mV to 181 mV with 4.5 at.% Ni doped in 1 M KOH. The Ni–MoSe 2 also characterizes excellent stability for 12 h with the formation of Ni–Se bond. The study of doping Ni in MoSe 2 nanosheets is of great guiding significance to the design and production of non-noble electrocatalysts for HER in alkaline media. • In synthesized process, ethanol makes Ni source evenly disperse in MoSe 2 nanosheets. • The Ni was doped in the inert planes of MoSe 2 , which increase active sites. • The Ni was firmly adhered in MoSe 2 nanosheets for the formation of Ni–Se bond. [ABSTRACT FROM AUTHOR]

Water stress is a major challenge present in drylands and it generally leads to an uneven progress in social, economic, and natural systems. However, its impact on the achievement of sustainable development goals (SDGs) in drylands remains unclear. By establishing a comprehensive assessment system incorporating SDGs progress evenness, this study has assessed water stress and its impact on sustainable development in Inner Mongolia, a typical and representative area of Eurasian drylands. Our results suggest that although Inner Mongolia has experienced rapid progress towards its SDGs, disregarding the evenness of SDGs progress overestimates the current situation and ignores regional gaps. Many poorly performing SDGs have made little progress over the past few decades, thus intensifying uneven progress goals. Further analyses have examined how water resources are associated with these problems. Moreover, multiple SDGs related to human essential needs and environmental conservation, including SDG 1 (no poverty), SDG 2 (zero hunger), SDG 3 (good health and well-being), SDG 7 (affordable and clean energy), and SDG 12 (responsible consumption and production), were significantly positively correlated with ecological water consumption, whereas SDGs related to economic growth, such as SDG 8 (decent work and economic growth), were positively correlated with industrial water consumption. These findings suggest that a conflict in water allocation for the achievement of different SDGs accounts for the uneven progress across the SDGs and therefore this impedes the sustainable development of these drylands. Therefore, we argue that industrial upgrading, regional planning, and management policies should be integrated into a single unified framework from an SDGs perspective to relieve water stress, thus promoting sustainable development in drylands. • Uneven progress and regional gap in achieving SDGs are induced by water stress and related tradeoffs across SDGs in drylands. • SDGs related to human needs and environmental protection are significantly positively correlated with ecological water use. • Disregarding SDGs progress evenness may overestimate progress and ignore regional gaps. [ABSTRACT FROM AUTHOR]

• The prototypic materials have been conducted to investigate the stratification behavior of the steady molten pool. • The synergistic effect of M Fe /M ∑ and Cn on redistribution of the corium components. • The reason for layer inversion of the molten pool occurred is studied. The prototypic materials have been used to investigate the stratification behavior of the steady molten pool at 3100 K in the context of the IVR condition. Induction heating in a cold crucible was used for melting of the 2 kg-scale UO 2 -ZrO 2 -Zr-Fe. A post-test examination of SEM, EDS, and XRD has been performed to investigate the metallic and oxide layers for all ingots. The effects of M Fe /M ∑ (initial iron to corium ratio) and Cn (initial degree of zirconium oxidation) on the configuration of the molten pool were studied. The results indicate that structure of the molten pools consists of the top light metallic layer and oxide layer. Nevertheless, a layer inversion may occur when the density of the metallic layer increased. The synergistic effect of M Fe /M ∑ and Cn on redistribution of the corium components leads to a significant increase of the uranium concentration for the metallic phase, which can explain why the layer inversion of the molten pool occurred. [ABSTRACT FROM AUTHOR]

• This article proposes virtual inertia and virtual damping based output impedance amplitude compensation control strategy to dampen oscillation of DC-side voltage. • The proposed virtual inertia control provide a amplitude compensation of output impedance, and damping the fluctuation of DC voltage caused by interaction between DC converter and the remaining networks of the DC microgrid. Voltage is prone to oscillation in a DC microgrid because of interaction between the power converter and the remaining parts of the networks. For this issue, this paper develops an impedance modeling based on linearization method for stability analysis. It is found that the wideband oscillation is prone to occurring concluded from stability analysis. Furthermore, the impact of parameters on stability of the microgrid is studied. Besides, a new closed-loop control model is proposed based on the DC current control loop. It is found that the current loop includes a peak which may impact the voltage oscillations. It is because voltages are interacted with the currents. Based on this idea, a new amplitude compensation control strategy based on virtual inertia emulation is proposed to dampen oscillation of the voltages by shaping the amplitude of output impedance. And theoretical analysis show good feasibility of the proposed control. Finally, the proposed conceives are demonstrated by experiments. [ABSTRACT FROM AUTHOR]

• This article proposes a VSM control strategy to dampen oscillation of DC-side voltage, and to improve damping performance and inertia for DC power system. • This paper proposed a new modeling method for identifying the dynamic interactions between multiple converters in a DC microgrid. DC system is characterized by low inertia and weak damping, which leads to a couple of stability issues. This paper proposes a modeling method for analyzing the DC-side oscillations occurred in DC microgrid with taking multi-paralleled converters into account. A new modeling is developed for analysis of dynamic interaction between multiple power converters. Thus, it is found that dynamic interaction between multiple converters will result in the poorly-damped oscillation of DC voltage. Besides, the poorly-damped modes will aggravate the stability of DC system. To cope with this issue, a virtual synchronous machine (VSM) control approach is proposed to suppress the oscillation of DC voltage, strengthen inertia, and improve damping performance of DC microgrid. Besides, the controller tuning of the VSM has a large flexibility that it does not depend on the system parameters. Finally, the proposed conceives are demonstrated by simulations. [ABSTRACT FROM AUTHOR]

Boron segregation and boride formation at grain boundaries are generally accepted in Ni-based superalloys. However, the addition of boron was found to result in the formation of a high density of nanosized M 5 B 3 (where M is a mixture of Cr, Mo) particles in γ/γ′ eutectics of a Ni-based superalloy during high-temperature creep in this work. M 5 B 3 phase precipitated at γ/γ′ eutectics keeps a well-defined orientation relationship with the eutectics, which is [001] γ/γ′ //[001] M5B3 , (020) γ/γ′ //(130) M5B3. And these nanosized borides could block dislocation slip, result in stress concentration surrounding γ/γ′ eutectics and facilitate crack initiation at γ/γ′ eutectic/matrix interface during the creep at high temperatures. • The structrural characteristic of γ/γ′ eutectics in a crept polycrystalline superalloy was analyzed. • High density of nano-sized M 5 B 3 -type boride precipitated at γ/γ′ eutectic regions was observed. • Nanosized borides can aggravate the deformation incompatibility of γ/γ′ eutectics during high temperature creep. [ABSTRACT FROM AUTHOR]

• Corn straw pyrolyzed with montmorillonite and FeCl 3 , magnetite and iron acetylacetone. • Montmorillonite and iron combined onto the biochar surface tightly. • Organometallic complexes such as Fe–O–C might form. • Magnetite can significantly improve the stability of biochar. In this study, corn straw biomass was co-pyrolyzed with a clay mineral (montmorillonite) in the presence of iron-bearing materials (FeCl 3 , magnetite and iron acetylacetone) and the prepared iron-montmorillonite biochars were characterized for their interfacial behavior. The results showed that, by adding iron to the pyrolysis process, organometallic complexes such as Fe-O-C were generated on the surface of biochars. All the iron-montmorillonite biochars were also shown to enhance the oxidation resistance likely by the increased relative contents of C O and COOH from 0% and 3.7% to 6.5–8.4% and 5.5–6.3%, respectively, compared with the iron-absent biochar. The measured carbon recalcitrance index (R 50 , bicohar) of iron-montmorillonite biochars in thermogravimetric analysis (TGA) also increased from 46.9% to 48.6–56.9%. Among the three types of added iron materials, magnetite showed the best performance in improving biochar stability. The study indicated that, when added together, montmorillonite and iron were effective in improving the stability of biochar, which displays an important environmental significance of carbon sequestration. [ABSTRACT FROM AUTHOR]

In the present study, the microstructure features and martensitic transformation behaviour of a Ni-Mn-Ga alloy were tailored by adjusting the Ag content. In addition, the effect of Ag content on the thermal stability was also explored. The results revealed that the non-modulated martensite phase and Ag particles coexisted in the Ni-Mn-Ga-Ag alloys. Different martensite variants were in the {112} type I twinning relationship. With increasing Ag content, not only all transformation temperatures but also the thermal hysteresis decreased continuously in a quasilinear manner. This was attributed to the introduction of small and soft Ag particles, which were applied to release the elastic energy during the martensitic transformation. The decreasing trend of elastic energy was highly nonlinear. The alloy with 4 at% Ag addition was the percolation threshold. In addition, the relationship of energy dissipation against Ag is not monotonic. While the energy dissipation of Ni 48 Mn 25 Ga 19 Ag 8 is almost zero, the others were much higher. Furthermore, unlike others, Ni 48 Mn 25 Ga 19 Ag 8 featured good martensitic transformation stability upon thermal cycling. • A series of Ni-Mn-Ga-Ag alloys were investigated. • NM martensite plates and Ag particles were observed in Ni-Mn-Ga-Ag alloy. • Transformation temperatures and hysteresis decreased by increasing Ag contents. • Ni 48 Mn 25 Ga 19 Ag 8 exhibited good thermal cycling stability. [ABSTRACT FROM AUTHOR]

Stimulation to local areas remarkably affects brain activity patterns, which can be exploited to investigate neural bases of cognitive function and modify pathological brain statuses. There has been growing interest in exploring the fundamental action mechanisms of local stimulation. Nevertheless, how noise amplitude, an essential element in neural dynamics, influences stimulation-induced brain states remains unknown. Here, we systematically examine the effects of local stimulation by using a large-scale biophysical model under different combinations of noise amplitudes and stimulation sites. We demonstrate that noise amplitude nonlinearly and heterogeneously tunes the stimulation effects from both regional and network perspectives. Furthermore, by incorporating the role of the anatomical network, we show that the peak frequencies of unstimulated areas at different stimulation sites averaged across noise amplitudes are highly positively related to structural connectivity. Crucially, the association between the overall changes in functional connectivity as well as the alterations in the constraints imposed by structural connectivity with the structural degree of stimulation sites is nonmonotonically influenced by the noise amplitude, with the association increasing in specific noise amplitude ranges. Moreover, the impacts of local stimulation of cognitive systems depend on the complex interplay between the noise amplitude and average structural degree. Overall, this work provides theoretical insights into how noise amplitude and network structure jointly modulate brain dynamics during stimulation and introduces possibilities for better predicting and controlling stimulation outcomes. Author summary: Despite the extensive application of local stimulation in cognition research and disease treatments, how regional perturbations alter brain-wide dynamics has not yet been fully understood. Given that noninvasive stimulation is associated with changes in the signal-noise relationship, we assume that noise amplitude is one of the plausible factors modulating the stimulation effects. Using a whole-brain biophysical model under different stimulation sites and noise amplitudes, we explore the influence of noise amplitude on stimulation effects and, more importantly, the interplay between noise amplitude and network structure. From a regional perspective, noise amplitude reduces the peak frequencies in unstimulated areas during stimulation. Moreover, we find a high similarity between the noise-averaged peak frequency matrix and the structural network. From a network perspective, we show that the changes in functional connectivity are decreased by noise amplitude, while the alterations in structural constraints display nonmonotonic trends. Intriguingly, increasing the noise amplitude in specific ranges can improve the association between network-level effects and structural degree, promoting better predicting and controlling therapeutic performance. Finally, the behaviors of cognitive systems quantified by network-level effects are jointly modulated by the noise amplitude and average structural degree. [ABSTRACT FROM AUTHOR]

This study investigates the effects of nitrogen (N) content (0.0005–0.0045 wt%) on the microsegregation, microstructures and high temperature mechanical properties of cast superalloy K417G. The results show that the segregation of Ti to interdendritic region becomes very serious with increased N content. In all three samples with different N contents, the alloys are typically dendritic morphology and γ′ phases show good cubic structure. With the N content increasing from 0.0005 wt% to 0.0045 wt%, the volume fraction of γ′ phase in the dendrite decreases, the sizes of γ/γ′ eutectic and MC carbide increase, and the volume fractions of γ/γ′ eutectic, MC carbide and micro-porosity firstly increase but then decrease. N addition changes the morphology of MC carbide from script-like shape to blocky shape, and Ti(C, N) is identified in the alloy with 0.0045 wt% N. With the N content increasing, the ultimate and yield strength decrease at elevated temperature, and the ductile and stress rupture life firstly have a sharp decrease and then have a slight increase. The specimen with the minimal content of N shows the best comprehensive mechanical properties. [ABSTRACT FROM AUTHOR]

Summary: Functional genomics, synthetic biology and metabolic engineering require efficient tools to deliver long DNA fragments or multiple gene constructs. Although numerous DNA assembly methods exist, most are complicated, time‐consuming and expensive. Here, we developed a simple and flexible strategy, unique nucleotide sequence‐guided nicking endonuclease (UNiE)‐mediated DNA assembly (UNiEDA), for efficient cloning of long DNAs and multigene stacking. In this system, a set of unique 15‐nt 3′ single‐strand overhangs were designed and produced by nicking endonucleases (nickases) in vectors and insert sequences. We introduced UNiEDA into our modified Cre/loxP recombination‐mediated TransGene Stacking II (TGSII) system to generate an improved multigene stacking system we call TGSII‐UNiE. Using TGSII‐UNiE, we achieved efficient cloning of long DNA fragments of different sizes and assembly of multiple gene cassettes. Finally, we engineered and validated the biosynthesis of betanin in wild tobacco (Nicotiana benthamiana) leaves and transgenic rice (Oryza sativa) using multigene stacking constructs based on TGSII‐UNiE. In conclusion, UNiEDA is an efficient, convenient and low‐cost method for DNA cloning and multigene stacking, and the TGSII‐UNiE system has important application prospects for plant functional genomics, genetic engineering and synthetic biology research. [ABSTRACT FROM AUTHOR]

Airborne array tomographic synthetic aperture radar (TomoSAR) is a major breakthrough, which can obtain three-dimensional (3D) information of layover scenes in a single pass. As a high-resolution SAR, airborne array TomoSAR has considerable potential for 3D applications. However, the original TomoSAR elevation resolution is limited by the baseline and platform length. In this study, a novel method for enhancing the elevation resolution is proposed. First, the actual curve trajectory observation model of airborne array TomoSAR is established. Subsequently, multi-channel image data are substituted into the model to obtain the observation equation. Furthermore, the azimuth and elevation directions of the two-dimensional observation scene are modeled uniformly. The scene reconstruction is realized through the two-dimensional joint solution. Finally, the observation equation is sparsely solved according to the sparse distribution characteristics of the target to obtain the image. The performance of the proposed method is verified via simulation and real-data experiments. The experimental results indicate that, compared with the traditional elevation resolution enhancement method, the proposed method improves the elevation resolution by two times. The proposed method also provides a new thinking for high-resolution SAR 3D imaging. [ABSTRACT FROM AUTHOR]

Silica nanoparticles (SiNPs) have been widely used in nanotechnology, and more attention has been paid to their safety evaluation. However, there are still inconsistent conclusions about the genotoxicity of SiNPs. A systematic review was conducted to explore whether SiNPs have genotoxicity followed by a meta-analysis of in vivo and in vitro murine genotoxicity tests. A total of 26 eligible studies were identified in this meta-analysis through a detailed process of inclusion and exclusion, which included 9 in vivo studies, 15 in vitro studies, and 2 in both. The results of in vitro studies showed that SiNPs exposure significantly increased the indicators of the comet assay, such as tail DNA content (T DNA%), tail length (TL), and olive tail moment (OTM). Indicators of mutagenicity had not been affected in vitro studies, such as mutation frequency (MF) and micronucleus (MN) frequency. There was a significant increase in MN frequency, but there was no influence on T DNA% in vivo. Results of subgroup analysis indicated that size and treatment time of SiNPs were the associated factors in vitro genotoxicity. The size of SiNPs, <21 nm, induced more DNA damage than larger sized SiNPs. It could induce MN formation when the treatment time of SiNPs was <12 h, and even more DNA damage when the exposure time over 12 h. SiNPs can induce genotoxicity both in vivo and in vitro. Comet assay may be more sensitive to detect in vitro genotoxicity, and MN frequency may be more suitable to detect in vivo genotoxicity. [ABSTRACT FROM AUTHOR]

• This article proposes a VSG CONTROL method to dampen oscillation of DC voltage, improve damping performance as well as inertia. • This paper analyzed the mechanism of VSG damping oscillation and improving damping performance of DC voltage in the framework of impedance modeling. DC-side oscillation problems trouble the stable and secure operation of voltage source converter high voltage direct current (VSC-HVDC) systems. Therefore, it is of considerable significance to investigate the physical origins of these oscillations. Thus, this paper proposes an impedance-based method for VSC-HVDC system DC stability analysis. Differently, a new perspective for DC resonance interaction is introduced, which is judged by the interactive behavior of two subsystems impedances, namely converter impedance and DC network impedance. Also, the proposed method quantitatively estimates the damping of DC schemes of VSC-HVDC system. Based on the proposed method, it is found that the global stability of VSC-HVDC system can be guaranteed if and only if: 1) subsystems are passive and locally stable, 2) there is no resonance interaction between inductive impedance and capacitive impedance, and 3) damping of DC system is large enough. Moreover, another contribution is to apply the virtual synchronous generator (VSG) control technique in VSC-HVDC system to dampen DC-side oscillation caused by impedance interaction. Specifically, this VSG control enhances inertia and damping of VSC-HVDC system on DC-side. Finally, the feasibility of the proposed technique and the accuracy of the mathematical model are demonstrated through simulation and experimental results. [ABSTRACT FROM AUTHOR]

Recently, the interplay between epidemic spreading and awareness diffusion has aroused the interest of many researchers, who have studied models mainly based on linear coupling relations between information and epidemic layers. However, in real-world networks the relation between two layers may be closely correlated with the property of individual nodes and exhibits nonlinear dynamical features. Here we propose a nonlinear coupled information-epidemic model (I-E model) and present a comprehensive analysis in a more generalized scenario where the upload rate differs from node to node, deletion rate varies between susceptible and infected states, and infection rate changes between unaware and aware states. In particular, we develop a theoretical framework of the intra- and inter-layer dynamical processes with a microscopic Markov chain approach (MMCA), and derive an analytic epidemic threshold. Our results suggest that the change of upload and deletion rate has little effect on the diffusion dynamics in the epidemic layer. [ABSTRACT FROM AUTHOR]

Metal carbides (MC) are typical strengthening phases in steels and superalloys. However, the decomposition of carbides can occur during high-temperature creep, which is generally considered to be detrimental to the high-temperature performance of superalloys. Here, through transmission electron microscopy and atomistic simulation, we report the atomistic to micro-scale mechanisms of MC decomposition. We identify that MC can deform plastically during high-temperature creep, which is supported by the observation of high-density dislocations within MC and steps at matrix/MC interfaces. This could release the stress concentration at the matrix/MC interfaces, thus improving the creep resistance. With Cr segregation along the dislocation line and continuous dislocation climb, decomposition of MC into M 23 C 6 occurs in grain interiors, which could lead to crack inside the MC carbides, i.e., fracture at the partially coherent M 23 C 6 /MC interfaces. This is new to the existing knowledge that MC decomposition and fracture occur at matrix/MC interfaces. [Display omitted] [ABSTRACT FROM AUTHOR]

In the present study, lightweight high-strength Ti-V-Al based high temperature shape memory composites were fabricated to broaden the application of shape memory alloys. In-situ TiB whiskers and La 2 O 3 particles were introduced and the distribution of reinforcements was optimized by the combination of low-energy milling, hot-press sintering and subsequent hot rolling. The in-situ reinforcements formed a network structure, which evolved from an equiaxed shape to an ellipsoidal shape. Furthermore, the direction of the reinforcement was inclined to the rolling direction. In the reinforcement-lean area, the phase constitution evolved from the β parent phase to the α″ martensite phase, and the width of the α″ martensite gradually widened with increasing distance to the in-situ reinforcements. The composites maintained high martensitic transformation temperature characteristics. Excellent mechanical properties with a high tensile strength of 885 MPa and a large elongation of 13.1% are obtained in the composite with a 1.0 wt% LaB 6 addition and 70% deformation ratio. Meanwhile, the composite realized 3.49% recoverable strain under 6% pre-strain conditions. • (TiB+La 2 O 3)/Ti-V-Al shape memory composites were successfully prepared. • The hot-rolled process optimized the direction of the reinforcement. • The A p was changed due to different hot-rolling ratio or LaB 6 addition. • The composites realize high strength, large elongation and recoverable strain. [ABSTRACT FROM AUTHOR]

• A sustainable livelihoods indicator across a geographical gradient of aridity was developed. • Sustainable livelihoods vary greatly across dryland zones. • Semi-arid zones have the most vulnerable livelihood rather than the arid zones. • The lack of physical capital and social capital is an important obstacle to sustainable livelihoods development in drylands. • Call for integrated land management and planning approach in drylands. Drylands cover about 41% of the Earth's land surface and are inhabited by more than two billion people, who rely on the diversified ecosystem services provided by drylands for their livelihoods. Achieving sustainable livelihoods (SLs) is a key component of achieving the sustainable development goals set by the agenda in 2030. Although it has aroused extensive interest, research on SLs in drylands at a regional scale is still limited. This paper aims to address this research gap by evaluating SLs through a geographic gradient of aridity in Inner Mongolia. A sustainable livelihood index (SLI) was developed using a wide range of indicators in a sustainable livelihood framework (SLF). The weight of the indicators was determined by the entropy weight method, and the characteristics of the spatial distribution of the SLI were analyzed. The results showed that the SLI varies greatly across aridity zones. In terms of livelihood assets, the SLI in the dry sub-humid zone was 15% higher than in the arid zones, while, surprisingly, semi-arid zones were found to have the most vulnerable livelihoods (rather than the arid zones). The reason for this is that land management and planning approaches are necessary in drylands. In further detail, Moran's I index illustrated that the overall performance of the SLI of each league or city has a positive spatial correlation, while through local spatial correlation it was found that Hinggan and Chifeng are hot spot areas and Hohhot is a cold spot area. The lack of physical and social capital is an important obstacle for SLs. Based on the analysis of SLs in Inner Mongolia, the characteristics of the sustainable development of local residents were revealed. In this paper, we call for an integrated (i.e., focusing on natural and human capital) land management and planning approach for drylands to reflect the nature of the tightly coupled socio-ecological systems. [ABSTRACT FROM AUTHOR]