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Glycemic traits are used to diagnose and monitor type 2 diabetes and cardiometabolic health. To date, most genetic studies of glycemic traits have focused on individuals of European ancestry. Here we aggregated genome-wide association studies comprising up to 281,416 individuals without diabetes (30% non-European ancestry) for whom fasting glucose, 2-h glucose after an oral glucose challenge, glycated hemoglobin and fasting insulin data were available. Trans-ancestry and single-ancestry meta-analyses identified 242 loci (99 novel; P-8), 80% of which had no significant evidence of between-ancestry heterogeneity. Analyses restricted to individuals of European ancestry with equivalent sample size would have led to 24 fewer new loci. Compared with single-ancestry analyses, equivalent-sized trans-ancestry fine-mapping reduced the number of estimated variants in 99% credible sets by a median of 37.5%. Genomic-feature, gene-expression and gene-set analyses revealed distinct biological signatures for each trait, highlighting different underlying biological pathways. Our results increase our understanding of diabetes pathophysiology by using trans-ancestry studies for improved power and resolution.A trans-ancestry meta-analysis of GWAS of glycemic traits in up to 281,416 individuals identifies 99 novel loci, of which one quarter was found due to the multi-ancestry approach, which also improves fine-mapping of credible variant sets.

Dry-wet cycles can cause fatigue damage to expansive soil, and various control parameters of the dry-wet cycles (initial moisture content, number of dry-wet cycles, cycle amplitude, etc.) can affect the development of soil damage. Therefore, it is important to study the fatigue damage characteristics of expansive soil under dry-wet cycles of constant amplitude. This paper considers expansive soil from Baise in Guangxi, China, as the research object. Based on tests of the P-wave velocity and low-stress shear strength of expansive soil under 0-6 constant amplitude dry-wet cycles, the attenuation laws for the P-wave velocity were analysed, the damage variable of expansive soil was characterized by P-wave velocity, and the rationality of this damage variable was verified by measuring the low-stress shear strength values of expansive soil specimens. Based on the experimental P-wave velocity results, a nonlinear empirical model of fatigue damage for expansive soil was constructed. The results illustrate that the P-wave velocity of an expansive soil sample decreases nonlinearly with an increasing number of dry-wet cycles and that the damage degree increases nonlinearly with an increasing number of cycles. The P-wave velocity can be successfully used to define a representative damage variable for expansive soil.

Existing single-axis acoustic levitation devices with an axisymmetric reflector can manipulate particles in a variety of ways. However, the mechanism by which particles are suspended in a single-axis acoustic levitator with a non-axisymmetric reflector remains poorly understood. This work addresses this issue by proposing a novel single-axis ultrasonic levitator design that includes a flat plane emitter and a screw-plane reflector. The node positions of the standing wave formed in this levitator were predicted by calculating the Gor’kov potential according to a numerical model. The analysis results demonstrate that the nodes were distributed off-axis and their positions varied in a spiral manner when changing the distance between the emitter and reflector. Corresponding experiments based on the proposed design were also conducted, and the results indicated that the distance changes between the emitter and reflector could induce some spiral trajectories of a polyethylene-foam particle placed in the ultrasonic field. Moreover, the trajectory of the suspended particle was found to distribute along a conical surface centered on the central axis of this device. This work provides a new approach for ultrasonic particle manipulation by changing the geometry of the reflector.

The dripping dynamics of the electromagnetically levitated (EML) liquid Ti–Al–Nb alloy under high temperatures was investigated by both numerical simulation based on the Arbitrary Lagrangian–Eulerian method and corresponding EML experiments. A dripping formation parameter εD was defined to describe the critical shape of alloy droplet. According to the simulated results, the high-temperature dripping phenomenon took place when εD < 0.68, which was in good agreement with experimental data. When dripping event occurred, the Lorentz force applied on alloy droplet decreased by approximately 11.7% within 0.07 s. Three typical methods were accordingly proposed to avoid the dripping failure of a bulk liquid Ti–Al–Nb alloy, which was implemented by enhancing electric current, adjusting levitation coil diameter, or increasing coil winding number. To control the droplet shape, the deformation pattern and the flow behavior of the liquid alloy were studied in a wide current range from 700 to 1400 A. With the increase in excitation current, the cone-shaped alloy melt transformed to a rhombus, and the flow behavior transformed from a typical four toroidal flow vortexes up to a complex eight toroidal flow vortexes. Moreover, the centroid position of liquid alloy rose up significantly at first and then slowly approached to levitation ceiling.

The thermophysical properties of liquid Zr–V alloys covering a whole composition range were systematically measured by an electrostatic levitation technique. A series of maximum undercoolings from 150 to 386 K (0.2 TL) was achieved for 11 different liquid alloys under containerless state and radiative cooling conditions, where Zr83.5V16.5 and Zr20V80 alloys displayed the strongest undercooling ability. The densities of liquid Zr–V alloys were measured over a wide temperature range from overheated to undercooled states, and the results exhibited a linear dependence on temperature for all 11 compositions. Two typical solidification pathways were observed for hypoeutectic alloys. Except for a slowing down of decreasing tendency near a eutectic Zr57V43 alloy, the liquid densities of Zr–V alloys almost decrease linearly with increasing V content. Accordingly, the thermal expansion coefficients of Zr–V alloys were also derived from containerless measurements, and they showed an increasing tendency with V content. Since thermal radiative dominated the heat transfer process, the ratio of isobaric specific heat to hemispherical emissivity was directly deduced from the thermal balance equation, leading to a quadratic relationship with temperature. It was found that the increase of V content enhanced the ability of radiative heat dissipation below 16.5 at. % V content.

Glycaemic traits are used to diagnose and monitor type 2 diabetes, and cardiometabolic health. To date, most genetic studies of glycaemic traits have focused on individuals of European ancestry. Here, we aggregated genome-wide association studies in up to 281,416 individuals without diabetes (30% non-European ancestry) with fasting glucose, 2h-glucose post-challenge, glycated haemoglobin, and fasting insulin data. Trans-ancestry and single-ancestry meta-analyses identified 242 loci (99 novel; P-8), 80% with no significant evidence of between-ancestry heterogeneity. Analyses restricted to European ancestry individuals with equivalent sample size would have led to 24 fewer new loci. Compared to single-ancestry, equivalent sized trans-ancestry fine-mapping reduced the number of estimated variants in 99% credible sets by a median of 37.5%. Genomic feature, gene-expression and gene-set analyses revealed distinct biological signatures for each trait, highlighting different underlying biological pathways. Our results increase understanding of diabetes pathophysiology by use of trans-ancestry studies for improved power and resolution.

Total mesorectal excision (TME) has been advocated as the golden standard of mid-low rectal cancer surgery for nearly 30 years. However, the complication of postoperative urinary and sexual dysfunctions due to intraoperative nerve injury has yet to be improved. Based on the concept of membrane anatomy, we carried out a systematic study on the important membrane anatomical structure anterior to the rectum--Denonvilliers' fascia. From multiple aspects including anatomy, physiology, histochemistry and surgical practice, we verified the importance of Denonvilliers' fascia for TME surgery in prevention of intraoperative nerve injury and postoperative urogenital dysfunction. Moreover, based on anatomical study of the surgical marker line of Denonvilliers' fascia (Wei's line) and surgical plane, we proved that total mesorectal excision with preservation of Denonvilliers' fascia (iTME) was feasible and practical. Therefore, we conducted a large multicentric randomized controlled trial (RCT). The mid-term result demonstrated that compared with traditional TME surgery, iTME was more effective in reducing the incidence of postoperative urinary and sexual dysfunctions in male patients with mid-low rectal cancer, without sacrifice of short-term tumor radical outcome. We believe that the final RCT result of iTME, based on membrane anatomy, will provide solid evidence for the update of concepts of rectal cancer surgery.全直肠系膜切除术（TME）成为中低位直肠癌手术的金标准已近30年，然而因TME术中神经损伤导致的术后排尿及性功能障碍至今仍未得到明显改善。基于膜解剖的理念，我们对直肠前方的重要膜解剖结构——邓氏筋膜进行了细致而系统的研究，从解剖、生理、组织、手术实践等多方面，验证了保留邓氏筋膜对TME术中神经保护及术后排尿和性功能障碍预防的重要作用；并通过邓氏筋膜术中标记线及手术入路的解剖研究，明确了保留邓氏筋膜全直肠系膜切除术（iTME）的可操作性。据此，我们开展了一项大型多中心随机对照研究，中期研究结果显示，与传统TME相比，iTME在不影响短期肿瘤根治效果的前提下，能更好地降低男性中低位直肠癌患者术后排尿及性功能障碍发生率。我们相信，基于膜解剖的iTME随机对照试验最终研究成果，将为直肠癌手术理念的更新提供夯实的循证医学证据。.

The Ni–Ni5Zr eutectic alloy becomes a promising structural material owing to its high strength and desirable plasticity. However, those nominal eutectic alloys with previously assumed compositions of Ni-8.8 at.% Zr and Ni-9.0 at.% Zr were found to involve a considerable amount of primary (Ni) phase. Hereby, an experimental study was conducted by differential scanning calorimetry and careful electron microscopy to clarify the situation. A total of 13 alloys in the composition range of 8.8 ~ 11.0 at.% Zr were explored with respect to their phase transition temperatures and microstructure evolution characteristics. The Ni-9.9 at.% Zr alloy exhibited primary (Ni) phase, whereas the Ni-10.1 at.% Zr alloy displayed primary Ni5Zr phase. Finally, the eutectic point was determined as Ni-10.0 at.% Zr alloy with a transition temperature of 1467 K, and the relevant part of Ni–Zr phase diagram was revised accordingly.

Significance The endocannabinoid system has a modulatory role in brain reward and cognitive processes. It has been hypothesized that repeated interference with endocannabinoid signaling (e.g., through abuse of cannabis or synthetic cannabinoids) can remodel the adolescent brain and make it respond differently to more addictive substances, such as cocaine. In the present study, we demonstrate that a history of synthetic cannabinoid exposure in adolescent animals results in distinct molecular and epigenetic changes following initial exposure to cocaine. These changes were pronounced in the prefrontal cortex and associated with an enhanced response to cocaine’s stimulatory effects. The prefrontal cortex is a brain region that still undergoes maturation in adolescence and its dysfunction contributes to the development of addictions., The initial response to an addictive substance can facilitate repeated use: That is, individuals experiencing more positive effects are more likely to use that drug again. Increasing evidence suggests that psychoactive cannabinoid use in adolescence enhances the behavioral effects of cocaine. However, despite the behavioral data, there is no neurobiological evidence demonstrating that cannabinoids can also alter the brain’s initial molecular and epigenetic response to cocaine. Here, we utilized a multiomics approach (epigenomics, transcriptomics, proteomics, and phosphoproteomics) to characterize how the rat brain responds to its first encounter with cocaine, with or without preexposure to the synthetic cannabinoid WIN 55,212-2 (WIN). We find that in adolescent (but not in adult) rats, preexposure to WIN results in cross-sensitization to cocaine, which correlates with histone hyperacetylation and decreased levels of HDAC6 in the prefrontal cortex (PFC). In the PFC, we also find that WIN preexposure blunts the typical mRNA response to cocaine and instead results in alternative splicing and chromatin accessibility events, involving genes such as Npas2. Moreover, preexposure to WIN enhances the effects of cocaine on protein phosphorylation, including ERK/MAPK-targets like gephyrin, and modulates the synaptic AMPAR/GluR composition both in the PFC and the nucleus accumbens (NAcc). PFC–NAcc gene network topological analyses, following cocaine exposure, reveal distinct top nodes in the WIN preexposed group, which include PACAP/ADCYAP1. These preclinical data demonstrate that adolescent cannabinoid exposure reprograms the initial behavioral, molecular, and epigenetic response to cocaine.

We investigate properties of nuclear matter and examine possible correlations with neutron star observables for a set of microscopic nuclear equations of state derived within the Brueckner-Hartree-Fock formalism employing compatible three-body forces. We find good candidates for a realistic nuclear EOS up to high density and confirm strong correlations between neutron star radius, tidal deformability, and the pressure of betastable matter. No correlations are found with the saturation properties of nuclear matter., Comment: 9 pages, 5 figures, accepted in European Physical Journal A (EPJA), Topical issue "First joint gravitational wave and electromagnetic observations: Implications for nuclear and particle physics"

Ultrasonic melt treatment is an environmentally friendly and no-polluting external field technology and has great application potential in materials fabrication. Power ultrasound with different intensities was introduced into the liquid phase separation and solidification process of ternary Al-45%Sn-5%Si immiscible alloy to explore the effects of ultrasound on the formation of macro- and microstructure. It was found that the previously apparent macrosegregation caused by the large density difference between immiscible liquid (Al) and (Sn) phases was gradually reduced and even suppressed with the increase of ultrasonic amplitude. Meanwhile, the ultrasonic waves also significantly modified monotectic structures, within which (Al) phase transformed from coarse dendrites to refined equiaxed grains, and (Si) phase evolved from long strips to small blocks. The introduction of ultrasound weakened the texture of solidified structure, whereas the growth orientation relationship between monotectic (Al) and (Si) phases remained unchanged. The theoretical analysis and calculation results indicated that ultrasonic cavitation and acoustic streaming were the dominant effects to modulate the macro- and microstructural evolution. This would improve the exploiting and utilization of immiscible alloys by ultrasonic processing technology.

The Ni-16 at. pct Zr hypoperitectic alloy melt was substantially undercooled using an electromagnetic levitator and a drop tube. The undercooling-induced competitive growth between the primary Ni7Zr2 and peritectic Ni5Zr phases was revealed by observing of the recalescence process in situ and confirmed by analyzing the solidified microstructures, X-ray diffraction pattern as well as dendritic growth velocity. When the liquid undercooling is less than a critical value of 106 K, the primary Ni7Zr2 phase initially precipitates from the parent liquid, which is subsequently followed by the nucleation and growth of the peritectic Ni5Zr phase around it. The solidified microstructure consists of the Ni7Zr2 phase, the Ni5Zr phase, and inter-dendritic eutectics. The orientation relationship and interface characteristics of the Ni7Zr2 and Ni5Zr phases were investigated by electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). The EBSD results clearly demonstrate that the Ni7Zr2 and Ni5Zr phases have the parallel relationship of {111}Ni7Zr2 // {111}Ni5Zr. TEM analysis reveals that a large-scale flat interface exists between the Ni7Zr2 and Ni5Zr phases, indicating good lattice matching of the two phases along the phase boundary. Once the critical undercooling is exceeded, the peritectic Ni5Zr phase preferentially nucleates and grows from the undercooled melt by completely suppressing the formation of the primary Ni7Zr2 phase. The EBSD analysis shows that the peritectic Ni5Zr phase is highly orientated and its growth mode is almost parallel to the 〈110〉 directions. When containerlessly solidified during free fall, typical peritectic microstructures form in large droplets, while only peritectic phase appears in the small droplets. This result further confirms the strong competition between the primary and peritectic phases in the Ni–Zr hypoperitectic alloy induced by large undercoolings.

The feasibility of non-destructive detection and classification of in-shell insect-infested almonds was examined by using multispectral imaging (MSI) technology combined with chemometrics. Differentiation of reflectance spectral data between intact and insect-infested almonds was attempted by using analytical approaches based on principal component analysis and support vector machines, classification accuracy rates as high as 99.1% in the calibration set and 97.5% in the prediction set were achieved. Meanwhile, the in-shell almonds were categorized into three classes (intact, slightly infested and severely infested) based on the degree of damage caused by insect infestation and were characterized quantitatively by the analysis of shell/kernel weight ratio. A three-class model for the identification of intact, slightly infested and severely infested almonds yielded acceptable classification performance (95.6% accuracy in the calibration set and 93.3% in the prediction set). These results revealed that MSI technology combined with chemometrics may be a promising approach for the non-destructive detection of hidden insect damage in almonds and could be used for industrial applications.

The liquid state property and intermetallic compound growth of Zr2Ni alloy were investigated by electrostatic levitation(ESL) technique. The relation between liquid undercooling and superheating followed a sigmoidal curve, which was probably attributed to the liquid structure transition. This assumption was supported by the density and viscosity measurement of liquid Zr2Ni alloy. Meanwhile, the diffusion-limited growth mechanism of Zr2Ni compound phase was demonstrated by the measured dendritic growth velocity. Within the undercooling range of 70–277 K(0.20 TL), the dendritic growth velocity displayed a parabolic relation versus undercooling, which achieved a maximum value of 27 mm s-1.

The thermodynamic parameters for a series of Fe(100−x)/2Co(100−x)/2Cux (x from 10 to 90, at. pct) alloys including their characteristic temperatures, the enthalpy and entropy changes of three phase transformations were determined systematically using differential scanning calorimetry (DSC). The corresponding vertical section of ternary Fe-Co-Cu phase diagram was predicted, and the relationships of the enthalpy and entropy changes vs Cu content were described by polynomial expressions. Metastable phase separation took place in those liquid Fe-Co-Cu alloys with the Cu content 30 ≤ x ≤ 70. The liquid phase separation temperatures were determined to outline the metastable miscibility gap, and the critical undercoolings to initiate phase separation were measured as a range of 57 K to 98 K. After such a phase separation, the liquid phase (to γ(Fe, Co)) exhibited the strongest undercooling ability in the Fe-Co-Cu alloys with x ≤ 70, whereas the solid-state undercooling for the eutectoid transformation is comparatively higher in the alloys with x > 70. The nanomechanical properties of α(Fe, Co) and (Cu) phases were measured by nanoindentation technique. In the Fe20Co20Cu60 alloy, both phases had the lowest nanohardness and reduced elastic modulus, and displayed severe creep behaviors, resulting mainly from its conspicuous liquid phase separation.

The evolution kinetics of microgravity facilitated spherical macrosegregation within model Fe-Cu immiscible alloys has been systematically investigated by drop tube experiments and 3D phase-field simulations. In microgravity environment, liquid phase separation of Fe-Cu alloys induced the appearance of spherical macrosegregation patterns with various core-shell structures. The formation probability and evolution characteristics of these phase-separated core-shell morphologies depended on the volume fraction of surface active Cu-rich liquid together with the cooling rate. As the cooling rate decreased, the duration time of phase separation extended and the formed dispersed structures showed a tendency to form as core-shell structures influenced by the effects of Marangoni convection and surface segregation. Meanwhile, core grew larger while the shell became thinner. The occurrence probability of spherical macrosegregation firstly increased and then decreased with the rise in the copper concentration, and core-shell morphologies changed from three-layer to two-layer which was accompanied by core shrinkage and shell thickening.

We experimentally and theoretically investigated the rapid solidification and microstructural evolution of freely falling droplets of the ternary Fe45Cu40Co15 peritectic alloy, with the critical undercooling temperature of metastable liquid phase-separation initiation being measured to be 38 K. We found that liquid phase separation occurs when the droplet diameter ranges from 80 to 980 μm, resulting in the formation of either microscopically or macroscopically segregated microstructures. The peritectic solidification microstructure was produced when the droplet diameter either exceeded 980 μm or was below 80 μm. The dispersed morphology of the large alloy droplets possessed nonuniformly dispersive characteristics, i.e., proximity to the droplet surface is negatively associated with the size of Cu-rich globules. With the further reduction of the droplet size, the phase-separated morphology first transformed into a core–shell structure and finally displayed a homogeneously dispersed structure. Our theoretical calculations showed that the residual Stokes motion, Marangoni convection, and surface segregation are the dominant dynamic mechanisms for the phase separation and microstructural evolution under reduced-gravity conditions inside the drop tube.

The bulk metallic electromagnetic levitation technique has a promising application prospect in condensed physics and materials science. In order to resolve the problem of weak levitation force and the small size of samples, an optimized solution based on finite element analysis (FEA) is developed to seek the best electromagnetic field distribution in the levitation zone. The influence of material properties on the distribution of magnetic flux density, surface pressure, and the Lorentz force were studied by the FEA method with various sample sizes of titanium and copper balls. The levitation capability of cylindrical coil system which consists of a single-layer coil with an inner diameter of 30 mm and the levitated object with a diameter of 20 mm was analyzed. To keep a balance between the turn number and increment efficiency of force, the best number of 7 turns is confirmed. Then, two types of optimized coils were predicted by numerical simulations, and the levitation force is improved drastically. The double-layer coil displays an outstanding levitation capability owing to the strong electromagnetic field generated by multilayer turns. In addition, 5 to 50 g aluminum, titanium, copper, and nickel are levitated by the above three kinds of coils and the levitation capacities are validated from the recorded data of the minimum operating current that can levitate the samples. The experimental results show good agreements with the simulation results, and the minimum current for optimized coils is reduced efficiently.

The liquid structures of undercooled Zr90Nb10, Zr70Nb30 and Zr50Nb50 alloys were studied by molecular dynamics simulation combined with electrostatic levitation experiments. The densities of three alloys were measured by electrostatic levitation to modify the Zr-Nb potential functions by adjusting parameters in potential functions. In simulation, the atomic packing in Zr-Nb alloys was more ordered at lower temperatures. The Voronoi tessellation analyses indicated Nb-centered clusters were easier to form than Zr-centered clusters although the Nb content was less than 50%. The partial pair distribution functions showed that the interactions among Zr atoms are quite different to that among Nb atoms.

The density of liquid Inconel 718 alloy was experimentally measured by electrostatic levitation technique, where the maximum undercooling of 100 K was realized for the commercial sample. The measured density of liquid Inconel 718 alloy is 7.39 g cm−3 at the liquidus temperature of 1663 K which was confirmed by DSC experiment, with the linear temperature coefficient of −6.89 × 10−4 g cm−3 K−1. Correspondingly, four ternary Ni-Cr-Fe compositions were designed to simulate the density of liquid Inconel 718 alloy with 16000 atoms, from which the liquid structure is revealed by pair distribution function. The predicted result shows a remarkable enhancement with the decrease of temperature at the first neighbor distance.

The knowledge of atomic structure for liquids, especially for liquid alloys with complex crystal structure and high liquidus temperatures, remains poorly understood. In this work, we have extended the development of deep neural network (DNN) potential for liquid Nb5Si3. The DNN potential captures the structural features of liquid alloys compared with ab initio results. The chemical short-range order parameter suggests that there exists strong affinity between Nb and Si atoms. The dynamic property was investigated, and the diffusion coefficient obeys the Arrhenius relationship. The atomic structure has been subsequently explored for normal and undercooled liquid Nb5Si3. Large amounts of fivefold symmetry Honeycutt–Andersen pairs have been identified in liquid Nb5Si3. However, due to the violent thermal motion in a high-temperature Nb5Si3 melt, icosahedral symmetry and distorted icosahedrons (ICOs) account for little proportion according to Voronoi polyhedron (VP) analysis. The effect of thermal motion on VPs has been discussed. Except from the well documented ⟨0,2,8,2⟩ and ⟨0,1,10,2⟩ distorted ICOs, six more quasi-ICOs (⟨0,1,9,3⟩, ⟨0,2,8,1⟩, ⟨0,2,8,4⟩, ⟨0,2,8,5⟩, ⟨0,1,10,3⟩, and ⟨0,1,10,4⟩) have been proven to deform from ICOs at high temperatures. The local environment motif obtained by the atomic cluster alignment method demonstrates the existence of dominant distorted ICOs. At last, the atomic structure during melting process is discussed by VP analysis. It is found that ⟨0,2,8,1⟩, ⟨0,2,8,2⟩, ⟨0,2,8,5⟩, and ⟨0,1,10,4⟩ prefer to form at the beginning of the melting but rapidly reduce when it is fully melted.

An intensive field of 20 kHz power ultrasound with various amplitudes was applied during the solidification process of quaternary Cu-7%Al-4%Ni-2.5%Mn single-phase alloy to investigate its dynamic solidification mechanism and mechanical performance improvement. It is found that α(Cu) phase nucleates at small undercoolings and mainly grows along (111) crystalline plane direction into coarse dendrites with developed secondary arms. With the rise of amplitude, ultrasonic wave increases the nucleation rate by improving the wetting effect between alloy melt and impurities and also breaks some growing dendrites into fragments. Once the ultrasonic amplitude reaches the maximum of 15.2 µm, the prominent cavitation effect further increases the nucleation rate by three orders of magnitude, and also leads to the symmetrical distribution of temperature field, solute field and flow field in the solidification front, eventually resulting in the formation of tiny equiaxed α(Cu) grains without any obvious preferred growth orientation, inside which the solute distribution also tends to become uniform. Meanwhile, the compressive yield strength of Cu-7%Al-4%Ni-2.5%Mn alloy is significantly increased by 3 times after ultrasonic solidification. Theoretical analysis indicates that grain strengthening and dislocation strengthening are the two main reinforcement factors induced by power ultrasound.

Post-bonded compression of TiAl/Ti2AlNb joint was conducted between deformation temperatures 950 °C and 1050 °C, with the strain rate range of 0.001 s−1–0.0001 s−1 and the height reduction of 50% in the present work. And the hot deformation behavior of the joint was investigated based on an analysis of the strain-stress curve, Arrhenius constitutive equation and processing map. The Arrhenius relationship (AR) and the parallel Arrhenius relationship (PAR) were established to describe the flow stress as a function of the strain rates and deformation temperatures. As a consequence, the average error between the AR and the PAR was only 1.1%, showing that the bonding interface has a feeble influence on the hot compression process of the joint. Moreover, an optimized processing map of the joint was constructed by overlaying the macro-instability map on the interfacial microstructure control region. The stability region of the joint was defined to this domain with the deformation temperature higher than 1050 °C and the strain rate lower than 0.0005 s−1. On balance, this work can be used to not only improve the hot working ability of the joint but also develop the interfacial microstructure of the joint.

Porous asphalt mixture (PAM) is an indispensable pavement material for the construction of sponge city with low-cost and environment friendly characteristics, which conducive to replenishing urban groundwater and alleviating the heat island effect. The main purpose of this article is to explore the change of road performance and water permeability of PAM under different diatomite dosage, and determine the optimal amount of diatomite content. First, the volume characteristics of diatomite permeable asphalt mixture (D-PAM) were measured by Darcy’s law, the void of D-PAM decreased slightly according to the test results. Furthermore, based on the water damage Marshall test and freeze-thaw splitting test, the water stability of D-PAM increases significantly with the increase of diatomite content. At last, the low-temperature anti-cracking performance and ductility of D-PAM were carried out based on the acoustic emission (AE) detector and the Low temperature universal mechanics testing machine. According to the experimental results, it is recommended that the content of diatomite is 10%.

Brittle compounds and large residual stresses are easily formed at the diffusion bonding (DB) joints of dissimilar intermetallic compounds, which will deteriorate the performance of the joints. In this study, in order to conduct an in-depth study of the strengthening mechanisms, the post-bonded heat treatment (PBHT) and post-bonded hot deformation (PBHD) were applied to the TiAl/Ti2AlNb DB joint. Comparative studies were implemented aiming to reveal the strengthening mechanisms and their influence on interfacial microstructure and mechanical properties. The experimental results indicated that the harmful intermetallic compound AlNb2 phase in the DB joint was eliminated by PBHT and PBHD. Meanwhile, the diffusion layers were changed from O + (AlNb2+α2) + (α2+β/B2+γ) three layers of DB joints to (α2+β/B2+O + Ti3NbAl2) + (α2+β/B2+γ) two layers of PBHD joint. Interestingly, the Ti3NbAl2 phase was first found in the DB joint after PBHD. After testing, the tensile strength and the relative tensile strength (defined as the tensile strength ratio of the joint and the TiAl alloy) of samples increased by 272.54 MPa and 39.2% after PBHD, respectively. In comparison, the tensile strength and the relative tensile strength of samples increased by 75.96 MPa and 10.96% after PBHT. This demonstrated that PBHD could induce the formation and uniform dispersion of the Ti3NbAl2 phase, which is indispensable to improve the tensile strength of the TiAl/Ti2AlNb DB joint.

We review the current status and recent progress of microscopic many-body approaches and phenomenological models, which are employed to construct the equation of state of neutron stars. The equation of state is relevant for the description of their structure and dynamical properties, and it rules also the dynamics of core-collapse supernovae and binary neutron star mergers. We describe neutron star matter assuming that the main degrees of freedom are nucleons and hyperons, disregarding the appearance of quark matter. We compare the theoretical predictions of the different equation-of-state models with the currently available data coming from both terrestrial laboratory experiments and recent astrophysical observations. We also analyse the importance of the nuclear strong interaction and equation of state for the cooling properties of neutron stars. We discuss the main open challenges in the description of the equation of state, mainly focusing on the limits of the different many-body techniques, the so-called "hyperon puzzle," and the dependence of the direct URCA processes on the equation of state., Comment: 83 pages, 17 figures, 617 references. Accepted for publication in Progress in Particle and Nuclear Physics

Dynamic recrystallization (DRX) mechanism of Ti-48Al-2Cr-2Nb (at. %) alloy was investigated by thermal uniaxial compression experiments in this work. The deformed microstructure showed that in addition to the discontinuous dynamic recrystallization (DDRX) with the typical feature of grain nucleation and growth, continuous dynamic recrystallization (CDRX) charactered by the crystal orientation accumulation also appeared in γ grains during the hot compression at 1200 °C/0.01 s−1. The crystal orientations of CDRX grains were nearly close to the 〈001〉 orientation at the strain of 0.92. Also, the emergence of DRX in the γ laths of lamellar colonies was confirmed by microstructure characterization, and the α2 → γ phase transformation occurred simultaneously. On the other hand, the GOS threshold value for distinguishing the deformed grains and DRX grains was analyzed to quantitatively calculate the DRX volume fractions. A novel hot processing map with the strain of 0.92 based on the DRX volume fraction was established to obtain the deformation parameters for the full DRX and provide the theoretical results for optimizing the thermo-mechanical treatment of TiAl alloy (approximately 1100 °C/0.001 s−1 and 1200 °C/0.01 s−1).

The rapid solidification of ternary Cr49.5Ni40.5Fe10 alloy was realized by triple containerless processing techniques including free fall, falling quench and direct quench in order to systematically investigate its eutectic growth mechanism under different heat transfer conditions. Based upon Newtonian cooling model and classical heat transfer equation, the thermal information inside alloy droplets was obtained to derive the cooling rate, temperature difference and temperature gradient. After containerless solidification, the macroscopic segregation of primary δ phase was remarkably reduced owing to the microgravity effect and the spherically symmetrical temperature field within alloy droplets. Three typical eutectic structures were observed in the alloy droplets. With the increases of cooling rate, temperature difference and temperature gradient, the microstructures of alloy droplets evolved from coarse lamellar eutectic to refined anomalous eutectic and finally transformed to coarse anomalous eutectic because of the independent growth of δ and γ phases. Especially, under falling quench condition, a non-uniform eutectic microstructure appeared, which was refined gradually from the surface to the center of alloy droplets. This was attributed to the sudden changes of these three thermodynamic parameters once the alloy droplets were rapidly quenched into liquid coolant.

The thermophysical properties of N36 type Zr-Sn-Nb-Fe alloy were investigated within the temperature range of 1750–2250 K. The liquid density at liquidus temperature and its temperature coefficient are determined as 6.28 g cm−3 and 2.78 × 10−4 g cm−3 K−1. The liquid thermal expansion coefficient at TL is 4.4 × 10−5 K−1. The liquid specific heat also displays a linear relationship versus temperature. The addition of alloying elements causes an apparent increase of specific heat, surface tension and viscosity. Moreover, both surface tension and viscosity display a larger change versus temperature in comparison with Zr.

Microgravity solidification provides a particular opportunity to produce an extraordinary microstructure and optimized mechanical properties. To shed further light on the influence of rapid solidification mechanism on mechanical properties, both the microgravity solidification mechanism and resultant micromechanical properties of ternary Al 57 Ag 12 Ge 31 alloy were analyzed by means of drop tube, nanoindentation and frictional sliding techniques, which was compared with equilibrium solidification condition. The solidification pathways changed with the decrease of droplet size, owing to a larger cooling rate and a higher undercooling. Consequently, the microstructure transformed from dendrites plus two-phase eutectic to two-phase eutectics, eventually to anomalous ternary eutectic, while the thickness of surface (Ge) layer decreased. The micromechanical properties of rapidly solidified alloy droplets were evidently improved with the decrease of droplet size, which is mainly ascribed to the microstructure refinement and the homogenous distribution especially of hardening (Ge) phase. The measured microhardness, yield strength, strain hardening exponent, pile-up resistance and friction coefficient were analyzed as a function of droplet size.

A series of upward seepage tests on unreinforced and reinforced sand specimens was conducted to investigate the influence of soil density and fibre parameters (i.e. fibre contents and lengths) on the piping failure mode, hydraulic conductivity k, and critical hydraulic gradient icr of fibre-reinforced soil (FRS). Direct shear tests were also performed to establish the relationships between soil shear strength and icr of FRS. A dataset of seepage tests on FRS was compiled from a literature review to assess the overall variation of k and icr with fibre content. The test results revealed that k decreases and icr increases as the fibre content increases. The fibre is more effective in dense specimens than in loose specimens. The test results also indicate the icr of FRS is strongly correlated to its soil shear strength. Finally, two case examples, unreinforced and reinforced embankments subject to flood-induced elevated water level, were analysed numerically. The numerical results demonstrated that the embankment backfilled with FRS possessed the combined merits of soil improvement in both mechanical and hydraulic performance. The use of FRS as backfill can effectively delay the advance of seepage, reduce soil piping potential, and improve system slope stability against seepage.

Liquid ternary Fe 50- x /2 Cu 50- x /2 Ge x ( x = 5 and 15) alloys were highly undercooled by glass fluxing technique, and the achieved maximum undercoolings are 300 K (0.18 T L ) and 268 K (0.16 T L ), respectively. At small undercoolings, these two alloys solidify in a normal pathway of peritectic solidification. If the alloy undercooling continues to increase beyond a certain value, metastable liquid phase separation takes place. The critical undercooling for Fe 47.5 Cu 47.5 Ge 5 alloy is 70 K and that for Fe 42.5 Cu 42.5 Ge 15 alloy is 110 K. At larger undercoolings, the homogeneous liquid alloy separates into an Fe-rich zone and a Cu-rich zone. In such a case, the undercooled alloy displays a monotectic solidification structure. The rapid solidification of the Fe-rich zone is the keystone of alloy solidification, and the growth velocity of the primary phase rises with increasing alloy undercooling according to a power law relation. Within the experimental undercooling ranges, the primary γ Fe phase of Fe 47.5 Cu 47.5 Ge 5 alloy attains a maximum growth velocity of 19 m/s, while the growth velocity of the primary Fe 0.84 Ge 0.16 phase reaches 11 m/s in undercooled Fe 42.5 Cu 42.5 Ge 15 alloy. Moreover, energy dispersive spectroscopy (EDS) analysis shows that the Fe-rich and Cu-rich liquid phases have a similar affinity with solute Ge.

The plateau pika (Ochotona curzoniae) is a species of sprint-running alpine animals in the Qinghai-Tibet Plateau, which is a harsh highland hypoxic environment. Ldh-c is expressed in the testis, sperm and somatic tissues of plateau pika. To reveal the role and physiological mechanisms of sperm-specific lactate dehydrogenase (LDH-C4), in plateau pika to adapt to hypoxic environment, an adenoviral line of pMultiRNAi-Ldhc was constructed and injected into the bilateral biceps femoris of the hind legs. The swimming times of the pikas, and the Ldh-c expression levels, total LDH activities and ATP levels in skeletal muscle, were measured after the pikas were raised in the trapped site for 5 days. Our results showed that after Ldh-c was silenced, the sprint-running ability (swimming time) of the plateau pikas was significant decreased, and the total LDH activities and ATP levels were reduced by 28.21% and 27.88%, respectively. Our results indicated that expression of Ldh-c in the skeletal muscle of plateau pika increased anaerobic glycolysis and enhanced adaptation to highland hypoxic environments., Summary: The expression of Ldh-c in the skeletal muscle of plateau pika (Ochotona curzoniae) increases anaerobic glycolysis, resulting in enhanced sprint-running capacity and adaptation to a hypoxic environment.

The physical mechanisms of crystal nucleation and dendritic growth within undercooled niobium were systematically studied by electrostatic levitation and molecular dynamics methods. The maximum undercooling was achieved as 454 K (0.16Tm), while the hypercooling limit was determined as 706 K (0.26Tm). The undercooling probability displayed Poisson distribution and indicated the occurrence of heterogeneous nucleation. The calculated critical nucleus size reduced rapidly with undercooling and the solid-liquid interface energy was deduced to be 0.367 J m−2. In addition, the dendritic growth velocity of pure niobium exhibited a power relation versus undercooling, and reached 41 m s−1 at the maximum undercooling.