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Abstract: Real-time sound source localization with microphone array still remains as a difficult task. The steered response power–phase transform (SRP–PHAT) method is proved to be robust, but it suffers from its high computational cost. In this paper, we propose a hybrid framework for real-time sound source localization with microphone array. The main concept is using the results of generalized cross correlation (GCC) based time difference of arrival (TDOA) estimation to narrow down the search space of SRP–PHAT. A circular clustering algorithm is developed to interlink the above two parts and calculate the extracted search space. The proposed hybrid method maintains the high localization accuracy of traditional SRP–PHAT algorithm, and the computational cost is much reduced. Moreover, any existing improvement of SRP algorithm can be directly incorporated into the hybrid framework to further improve performance. Experiment and simulation results validate the efficiency and accuracy of the proposed method. [Copyright &y& Elsevier]

Neurodevelopmental disorders (NDDs) usually present overlapping symptoms. Abnormal white matter (WM) microstructure has been found in these disorders. Identification of common and unique neural abnormalities across NDDs could provide further insight into the underlying pathophysiological mechanisms. We performed a voxel-based meta-analysis of whole-brain diffusion tensor imaging (DTI) studies in autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder (ADHD) and other NDDs. A systematic literature search was conducted through March 2020 to identify studies that compared measures of WM microstructure between patients with NDDs and neurotypical controls. Peak voxel coordinates were meta-analyzed via anisotropic effect size-signed differential mapping (AES-SDM) as well as activation likelihood estimation (ALE). Our final sample included a total of 4137 subjects from 66 studies across five NDDs. Fractional anisotropy (FA) reductions were found in the splenium of the CC in ADHD, and the genu and splenium of CC in ASD. And mean diffusivity (MD) increases were shown in posterior thalamic radiation in ASD. No consistent abnormalities were detected in specific learning disorder, motor disorder or communication disorder. Significant differences between child/adolescent and adult patients were found within the CC across NDDs, reflective of aberrant neurodevelopmental processes in NDDs. The current study demonstrated atypical WM patterns in ASD, ADHD and other NDDs. Microstructural abnormalities in the splenium of the CC were possibly shared among ASD and ADHD. • Common white matter abnormalities were identified in the splenium of corpus callosum in ASD and ADHD. • White matter compromised in the genu of CC in ASD but not ADHD, suggested a wider abnormal pattern in ASD. • No white matter alterations were detected in communication disorder, specific learning disorder and motor disorder. • Compared with children and adolescents, adults impaired more severely in the CC. • Two neuroimaging meta-analytic methods, AES-SDM and ALE were used. [ABSTRACT FROM AUTHOR]

Cumulative evidence has showed the deficits of inhibitory control in patients with attention deficit hyperactivity disorder (ADHD), which is considered as an endophenotype of ADHD. Genetic study of inhibitory control could advance gene discovery and further facilitate the understanding of ADHD genetic basis, but the studies were limited in both the general population and ADHD patients. To reveal genetic risk variants of inhibitory control and its potential genetic relationship with ADHD, we conducted genome-wide association studies (GWAS) on inhibitory control using three datasets, which included 783 and 957 ADHD patients and 1350 healthy children. Subsequently, we employed polygenic risk scores (PRS) to explore the association of inhibitory control with ADHD and related psychiatric disorders. Firstly, we identified three significant loci for inhibitory control in the healthy dataset, two loci in the case dataset, and one locus in the meta-analysis of three datasets. Besides, we found more risk genes and variants by applying transcriptome-wide association study (TWAS) and conditional FDR method. Then, we constructed a network by connecting the genes identified in our study, leading to the identification of several vital genes. Lastly, we identified a potential relationship between inhibitory control and ADHD and autism by PRS analysis and found the direct and mediated contribution of the identified genetic loci on ADHD symptoms by mediation analysis. In conclusion, we revealed some genetic risk variants associated with inhibitory control and elucidated the benefit of inhibitory control as an endophenotype, providing valuable insights into the mechanisms underlying ADHD. [Display omitted] • Several significant loci and risk genes were identified for inhibitory control in healthy controls and ADHD patients. • The genetic loci related to inhibitory control highly affect the function of neurons and the brain. • Inhibitory control is genetically associated with attention deficit hyperactivity disorder and autism. • Inhibitory control acts as a mediator of a pathological process from risk genes to ADHD. [ABSTRACT FROM AUTHOR]

L1 2 -strengthened high entropy alloys (HEAs) usually suffer from severe intermediate-temperature embrittlement. In this study, we revealed that the intermediate-temperature embrittlement of a (Ni 2 Co 2 FeCr) 92 Nb 4 Al 4 L1 2 -strengthened HEA originates from the severe oxidation of intergranular D0 19 precipitates which weakens the grain-boundary cohesion. With the minor addition of 1.5 at% Si, we successfully achieved a brittle-to-ductile transition in the alloy via alleviating intergranular oxidation. The alloyed Si preferentially partitioned into the intergranular precipitates, significantly improved their oxidation resistance and pinning effects on the grain boundaries, which effectively mitigated environmentally assisted grain-boundary damage and thus suppressed the crack propagation upon deformation. [Display omitted] • L1 2 -strengthened high entropy alloys (HEAs) usually suffer from severe intermediate-temperature embrittlement. • A brittle-to-ductile transition at intermediate temperatures was achieved in a Si-doped (Ni 2 Co 2 FeCr) 92 Nb 4 Al 4 HEA. • The embrittlement of the Si-free alloy originates from the severe oxidation of intergranular precipitates. • The alloyed Si preferentially partitioned into the intergranular precipitates, significantly alleviating the intergranular oxidation. [ABSTRACT FROM AUTHOR]

The study explored the oxidation behaviors of a Ni-Co-based superalloy at temperatures between 900–1100 °C in air, employing a weighing method and multiscale characterization techniques. The findings indicate that the superalloy adheres to parabolic kinetics and develops a complex, four-layer oxide scale comprising a TiO 2 layer, Co(Al, Cr) 2 O 4 layer, Cr 2 O 3 layer, and (Ti, Nb) 2 O 5 layer. The excellent oxidation resistance is primarily attributed to the formation of the TiO 2 and Co(Al, Cr) 2 O 4 layers. These layers contribute to reducing the evaporation of Cr 2 O 3 and the development of the (Ti, Nb) 2 O 5 layer, which in turn helps mitigate the exfoliation of the oxide scale. • A Ni-Co-based superalloy is oxidized in air at 900-1100 ℃. • The surface oxide scale is found to have a complex four-layered structure. • TiO 2 layer and Co(Al, Cr) 2 O 4 layer decreases the evaporation of the Cr 2 O 3 oxides. • The formed internal (Ti, Nb) 2 O 5 layer alleviates the oxide scale exfoliation. [ABSTRACT FROM AUTHOR]

For precipitate-strengthened alloys, the decomposition of the precipitates at the subsurface during high-temperature oxidation is detrimental to mechanical properties. In this study, we adjusted Al concentrations in Fe 71.5-x (Ni, Cr, Ti) 28.5 Al x (x = 8, 12, and 16 at%) complex concentrated alloys (CCAs) to precipitate elongated cuboidal L2 1 with higher density and Al concentration, as well as reduced inter-precipitate spacing. This is more conducive to the rapid diffusion of Al to the matrix and grain boundaries, promoting the formation of a continuous and compact Al 2 O 3 layer with random crystallographic orientation at 800 °C in air. This not only inhibits the further decomposition of the L2 1 phase but also avoids internal oxidation and nitridation. • Oxidation kinetics of AlCrFeNiTi CCAs at 800 °C do not obey parabolic relationship. • Al induces the transformation from the CrTi 2 O 5 +Cr 2 O 3 to a single Al 2 O 3 oxide layer. • The Ti-rich oxides were formed ahead of the Al 2 O 3 at the grain boundary. • Al 2 O 3 oxide scale hinders the L2 1 decomposition, internal oxidation, and nitridation. • A model for oxidation resistance of this CCA affected by Al was proposed. [ABSTRACT FROM AUTHOR]

The presence or ingression of hydrogen (H) can dramatically embrittle a broad range of intrinsically ductile metals and alloys. Despite extensive research, fundamental understanding of hydrogen embrittlement (HE) and mitigation methods remain far from complete. Here, we present a thermodynamic approach to robustly enhance resistance to HE in CrCoNi with minor degradations of other properties. Specifically, 6 at. % W/Mo are doped and induced to segregate into grain boundary (GB) regions, which restores ductile transgranular fracture with dimpled fracture surfaces and tensile ductility losses of ∼ 10 − 30 % under gas-H-charged conditions. Density functional theory (DFT) calculations and Monte Carlo (MC) simulations reveal W-GB-segregation energies and favourable W-GB-segregations over a wide temperature window, as well as H-dissolution energies in grain interiors and GB regions. MC simulations with these DFT-based energetics show that most H-atoms reside in grain interiors in all alloys, but the GB-H-occupation ratios are ∼ 1 − 2 orders-of-magnitude higher in the undoped alloy. In the doped alloys, W-GB-segregations moderately enhance GB cohesion and more importantly, make GB regions less attractive for H-dissolution, which in turn drastically reduces GB-H-occupation at the most critical low/room-temperatures. The stark differences in GB-H-occupation ratios in the doped and undoped alloys corroborate their respective void-coalescence and GB-cleavage dominant fracture mechanisms. The enhanced HE resistance is derived from GB-solute-segregation and reduced GB-H-occupation, both of which are thermodynamic equilibrium properties of the underlying alloy system. The combined experiments and simulations demonstrate a general strategy to design structural alloys for enhanced resistance to HE, which may be applicable to other alloy systems. [Display omitted] [ABSTRACT FROM AUTHOR]

Cobalt-based γ'-strengthened superalloy exhibits tremendous potential in numerous fields, such as power generation equipment and the aerospace industry. The characteristics of laser powder bed fusion technology have aligned well with the demands for superalloy's strong texture or single crystal microstructure. However, the post-heat treatment processes often disrupt the initial microstructure of the as-printed parts due to unavoidable recrystallization. In this study, we obtained a strong <101> texture in an as-printed Co-5Al-14V (at.%) ternary cobalt-based superalloy, which is difficult to achieve in nickel-based superalloys. Intriguingly, this <101> texture remains thermally stable even after aging treatment at a near γ' solvus temperature. Hence, a <101> textured microstructure with an evenly distributed γ'(L12) precipitates was attained, which benefits the improvement of high-temperature creep resistance. The unique microstructure characteristics revealed in this work can be beneficial for the development of cobalt-based superalloys and shed light on the microstructural engineering of other LPBF-manufactured superalloys. [Display omitted] [ABSTRACT FROM AUTHOR]

As a newly emerged class of materials, chemically complex intermetallic alloys (CCIMAs) with exceptional thermal and mechanical properties are a promising candidate for high-temperature structural use. However, serious intergranular embrittlement at intermediate temperatures (600∼800 °C) is frequently found in those CCIMAs, obstructing their large-scale engineering applications. In this study, through deliberately tailoring thermomechanical processing, we designed a lamellar-structured (LS) L1 2 -type Co-Ni-Al-Ti-Ta-Nb-B-based CCIMA that effectively overcomes this critical issue. The LS-CCIMA exhibits an excellent yield strength (YS) of ∼1.0 GPa with a large tensile elongation of ∼17% at room temperature. More prominently, it also presents an anomalous YS of ∼1.2 GPa combined with an acceptable tensile elongation of ∼10% at intermediate temperatures ranging from 600 to 800 °C, outperforming those of many other simple ordered intermetallics and conventional superalloys. Such superb immediate-temperature strengths primarily originate from the high anti-phase boundary energy caused by the addition of multiple alloying elements (Ti, Ta, and Nb) and the pile-ups of geometrically necessary dislocations. Moreover, we attribute the acceptable tensile plasticity to the increased plastic deformation capacities from the activation of various deformation-induced substructures (e.g., dislocation pairs at 600 °C and superlattice intrinsic stacking faults at 800 °C) and the inhibiting mechanisms of the lamellar structures on oxygen-induced grain boundary damage and microcrack's propagation. This work provides a new pathway for the innovative design of strong-yet-ductile heat-resistant CCIMAs. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract The composition evolution of γ′ nanoparticles as a function of aging duration in the Ti-doped CoFeCrNi high entropy alloy was studied by atom probe tomography (APT) and first-principle calculations. The APT results indicate that the evolution behaviors of Co, Fe, and Cr in the Ni 3 Ti-type γ′ nanoparticles are significantly different. Co saturates to a stable concentration in the γ′ nanoparticles rapidly in the initial stage of the precipitation, whereas Fe and Cr atoms are incorporated into the γ′ nanoparticles during the coarsening. The APT results are supported by the first-principle calculations from the perspective of the electronic state. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) show common brain area abnormalities, which may contribute to the high shared co-occurrence symptoms and comorbidity of the two disorders. However, neuroanatomic anomalies in neurodevelopmental disorders may change over the course of development, and the developmental variation of these two disorders is unclear. Our study conducted a systematic literature search of PubMed, Web of Science, and EMBASE databases to identify disorder-shared abnormalities of white matter (WM) from childhood to adulthood in ADHD and ASD. 28 ADHD and 23 ASD datasets were included in this meta-analysis and were analysed by AES-SDM to detect differences in fractional anisotropy in patients compared to typically developing individuals. Our main findings reveal the variable WM developmental trajectories in ADHD and ASD respectively, and the two disorders showed overlapping corpus callosum tract abnormalities in their development from children to adults. Furthermore, the overlapping abnormalities of the corpus callosum tract increased with age, which may be related to their gradually increasing shared symptoms and comorbidity in these two disorders. • Clinical overlap between ADHD and ASD is increasingly appreciated, but the underlying brain mechanisms remain unknown to date. • The first direct coordinate-based brain imaging comparison between ADHD and ASD through childhood to adulthood. • The two disorders showed increased overlapping corpus callosum tract abnormalities in their development from childhood to adulthood. [ABSTRACT FROM AUTHOR]

The oxidation behaviors of a newly-designed L1 2 -strengthened multi-component Ni-Co-Fe-Cr-Al-Ti-Nb system were studied at 800 ℃, where the synergistic alloying effects of Ti, Nb, and Cr on the oxidation resistance were uncovered. The findings show that the doping of Ti facilitates the outward diffusion of metal cations and inward diffusion of oxygen ions through the Cr 2 O 3 and Al 2 O 3 scales, deteriorating the oxidation resistance. By substituting the Ti with Nb, a continuous and dense Al 2 O 3 scale was potentially promoted benefiting from the "unlocked" Al atoms from the L1 2 particles. The increased additions of Cr and Nb contribute to the improved oxidation resistance. • Excellent strength and ductility combinations were achieved in this L1 2 -strengthened high-entropy alloy (HEA) system. • The element-mediated oxidation behaviors and mechanisms in the L1 2 -strengthened HEAs were studied. • The doping of Ti facilitates the outward and inward diffusions of ions through the Cr 2 O 3 and Al 2 O 3 scales. • The elevated additions of Cr and Nb contribute to the improved oxidation resistances for high-temperature applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co 16 X 6 Si 7 -G (X = Ti, Nb, Ta) phase serves as a ferrite strengthening medium for the first time. • Density function theory calculations predict that the Co 16 X 6 Si 7 -G (X = Ti, Nb, Ta) match the best with ferrite among all 12 Co 16 X 6 Si 7 -G compounds. • Co 16 X 6 Si 7 -G (X = Ti, Nb, Ta) phases strengthened ferritic steel exhibits significant age-hardening and a good strength-ductility compromise. This work aims to develop a novel Co 16 X 6 Si 7 -G (X = Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Tc, Re) phase strengthened ferritic steel with the help of first-principles calculations. Ddensity function theory calculation results demonstrated that the Co 16 X 6 Si 7 -G phase possesses the advantage of good thermodynamic stability and low misfit with the ferritic matrix. On the basis of calculation, we successfully prepared three model alloys, i.e., the Fe20Cr5Co2Si1Ti, Fe20Cr5Co2Si0.75Nb and Fe20Cr5Co2Si1.5Ta (wt.%), who make a good trade-off between strength, ductility and good oxidation/corrosion resistance. Our observation verified that the Co 16 X 6 Si 7 -G phase can precipitate within 1 h with proper heat treatment, showing a cube-on-cube orientation relationship with its parent matrix. The introduction of G phase precipitates amazingly increases the micro-hardness of model alloys by ∼ 160 HV after aging at 873 K. And the precipitates within the ferrite phase have not been observed to grow coarser even after 96 hrs aging treatment. Furthermore, excellent mechanical properties of ∼ 1.2 GPa tensile strength and ∼ 10 % total elongation have been achieved after 6 hrs aging time at 873 K. These findings indicate the Co 16 X 6 Si 7 -G phase would be a promising candidate as a strengthening medium and provide valuable insight into the screen of precipitates for the development of high-strength and ductile steels. [ABSTRACT FROM AUTHOR]

Oxidation behavior and mechanical properties of two L1 2 -strengthened high-entropy superalloys (HESAs), i.e., (Ni 2 Co 2 FeCr) 92 Ti 4 Al 4 and (Ni 2 Co 2 FeCr) 92 Nb 4 Al 4 , were systematically investigated at 700 ℃. Our results reveal that the oxidation resistance was significantly improved by the replacement of Ti with Nb with slightly optimized mechanical performance. The substitution of Ti by Nb promotes the formation of continuous Cr 2 O 3 , AlNbO 4 , and Al 2 O 3 layers, and causes a remarkable improvement in oxidation resistance, thus highlighting the greater potential of Nb-bearing HESAs to function as the elevated-temperature structural materials. The underlying mechanisms for the superior mechanical properties and oxidation resistance of the Nb-bearing HESA were carefully discussed. • The oxidation behavior and mechanical properties of two different L1 2 -strengthened HESAs were studied at 700 ℃. • The Nb-bearing HESA shows superior oxidation resistance than the Ti-bearing one without sacrifice of mechanical properties. • The discontinuous Al 2 O 3 formed in the Ti-bearing HESA cannot effectively block cation diffusion. • The low oxidation rate of the Nb-bearing HESA is attributed to the formation of triple-layered continuous oxide scales. [ABSTRACT FROM AUTHOR]

L1 2 -phase-strengthened high entropy alloys (HEAs) have shown promising mechanical properties for both high-temperature and cryogenic applications. However, designing L1 2 phase still strongly relies on the trial-and-error experiments. The current study reported that the L1 2 phase in face centered cubic (FCC) HEAs is greatly influenced by a sygnergistic effect of Ti and Al. The experimental results showed that a Ti/Al ratio ranging from 0.7 to 2 was required by L1 2 phase in CoCrFeNi-based HEAs. The present findings provided an efficient guideline for designing L1 2 phase in the complex concentrated alloys. • The relative contents of Ti and Al play a critical role in the formatiom of L1 2 -phase. • The Ti/Al ratios ranging from 0.7 to 2 would prefer the formation of L1 2 phase in the CoCrFeNi-based HEAs. • In the complex FCC alloy systems, Ti is a main L1 2 phase former and Al is a L1 2 phase stabilizer. [ABSTRACT FROM AUTHOR]