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Four porous corundum‐spinel aggregates were prepared from magnesia and α‐Al2O3 micropowder via the Kirkendall effect. Effects of the particle size of magnesia (PSM, 0–74 μm, 0–15 μm, and 0–44 μm) and firing temperature (1100–1600°C) on the phase compositions, microstructures, pore characteristics of the prepared porous aggregates were investigated. As the firing temperature increased, the PSM influenced the reaction rate of magnesia and alumina, and the sintering process, leading to remarkable changes in the phase compositions, porosity, and microstructure with a negligible impact on the pore size distribution. As the PSM decreased from 0–74 μm to 0–15 μm, the apparent porosity initially increased and then decreased. Relatively compact cyclic spinels formed around the Kirkendall pores in aggregates with 0–74 μm and 0–44 μm magnesia added after fired at 1600°C, as the expansion of spinel formation was inhibited by the high strength of the alumina matrix. Finally, the optimized product is an aggregate with 0–44 μm magnesia added, which exhibits a high total porosity of 32.4%, a low bulk density of 2.69 g/cm3, and a thermal conductivity of 2.178 W/(m·K) at 1000°C, as well as a high compressive strength of 302.5 MPa and a small median pore size of.46 μm. This work provides a promising technique for preparing porous‐corundum‐based aggregates. [ABSTRACT FROM AUTHOR]

To extend the practicability of ceramics in immobilizing nuclear waste with fluctuant composition, structural design should be abandoned. The simulated tetravalent actinide waste An4+ (Ce4+) was directly doped into prepared Gd2Zr2O7, and the waste forms were synthesized by high‐temperature solid‐state reaction. It has been shown that the maximum loading of CeO2 in Gd2Zr2O7 lies between 20 and 30 wt.%, and Ce elements are uniformly distributed in the matrix. Existing in Ce3+ and Ce4+, cerium ions automatically occupied both the Gd and Zr sites in Gd2Zr2O7 according to valence equilibrium. This occupation causes the change of r(A3+)/r(B4+) and eventually leads to the structure transition from pyrochlore to fluorite. In addition, the normalized leaching rate of the sample with 60 wt.% of dopant was about 2.5 × 10−7 g m−2 d−1 on the 35th day. In this study, a free occupation of simulated waste ions in ceramics was proposed. [ABSTRACT FROM AUTHOR]

Introduction: This study aimed to investigate the treatment effect of G protein‐coupled receptor 30 (GPR30) agonist G1 combined with hypothermia (HT) on cognitive impairment and anxiety‐like behavior after subarachnoid hemorrhage (SAH) in rats. Methods: Fifty male rats were randomly assigned to one of five groups: Sham group, SAH group, SAH + G1 group, SAH + HT group, and SAH + G1 + HT group. The SAH rat model was established by modified endovascular puncture in all groups except the Sham group. Neurological function after the operation was assessed by Garcia scoring. The degree of rat cerebral edema was determined using dry‐wet weighing method on the 28th day after operation. Moreover, the behavioral test was performed on rats on the 4th and 28th days after operation. Results: Compared with Sham group, the Garcia score of each SAH rat model group decreased significantly on the first day and thereafter increased gradually. However, the recovery rate of each treatment group was higher than the SAH group (no treatment), and the Garcia score of SAH + G1 + HT group was much higher than the SAH group on the seventh day after operation. In addition, each treatment group could obviously reduce the cerebral edema degree of SAH rats, among which rats in SAH + G1 + HT group had lower cerebral edema degree than SAH + G1 group and SAH + HT group. Behavioral test results showed that the combination of GPR30 agonist G1 and HT markedly improved the learning and memory ability of SAH rats, alleviated their anxiety‐ and emotion‐related behavior, and enhanced their social interaction. Conclusion: GPR30 agonist G1 combined with HT reduces cognitive impairment and anxiety‐like behavior in rats with SAH. [ABSTRACT FROM AUTHOR]

Extreme events have become more frequent in the Northern Hemisphere mid‐latitudes in recent decades, hugely impacting the ecosystem and society. The quasi‐resonance amplification (QRA) of planetary waves is considered one of the dynamic mechanisms leading to extreme weather. However, the specific impact of resonant waves caused by QRA on surface heat extremes is still an open issue. Here we show that the QRA of planetary waves leading to heat extremes is closely related to double jets, accompanied by the enhancement of atmospheric blocking and the weakening of planetary wave escaping into the stratosphere. Our results illustrate the important role of mid‐latitude planetary waves with zonal wavenumber m = 6–8 caused by QRA in the increasingly frequent heat waves in recent years, as it can increase the coverage area and occurrence frequency of heat extremes in mid‐latitudes and show a significant impact on preferred regions, especially in Eurasia. Plain Language Summary: In the summer of 2022, the Northern Hemisphere mid‐latitudes were affected by widespread, intense heat waves that developed more quickly than climatologists had expected, hugely impacting the ecosystem and society. Understanding the extent and causes of extreme heat can help local authorities better prepare for the extreme weather that may occur in the near future. Planetary wave, also known as Rossby wave, manifested as a large‐scale oscillation of the midlatitude atmospheric flow, usually forms a snaking shape over the Earth, leading to persistent surface weather systems and often resulting in extreme events. Existing studies have shown that, planetary wave is one of the important dynamic mechanism behind heat waves. At certain frequencies and wavelengths (short‐wavelength), this circumglobal waves disturbance can be significantly amplified through resonance, resulting in heat extremes. Our work indicates that resonant wave plays an increasingly important role in heat events over Northern Hemisphere mid‐latitudes. The long‐term changes in resonant wave trend deserve continuous attention, because an improved understanding of planetary waves behind extreme events can help assess future wave activity's potential social and economic effects. Key Points: The influence of resonant waves on heat extremes in the Northern Hemisphere mid‐latitude summer is increasing, especially in EurasiThe occurrence of resonant waves is closely related to double jets, accompanied by the enhancement of atmospheric blockingThe occurrence of resonant waves is accompanied by the weakening of the upward‐propagating planetary waves [ABSTRACT FROM AUTHOR]

In this study, we report the petrography and mineralogy of a brecciated eucrite Northwest Africa (NWA) 8021, which shows a locally layered texture with one layer containing graphic clasts and Si,Ti‐rich regions. The graphic clasts contain rod‐like grains of silica phases, augite, K‐feldspar, and Ca‐phosphate minerals included in anorthite. Some of the clasts contain relatively coarse grains of quartz, K‐feldspar, and augite, which are chemically different from the rod‐like phases, indicating different origins. All of the augite grains in the graphic clasts have rare earth element (REE) concentrations higher than those in typical eucrites. The bulk Na2O+K2O contents of the graphic clasts are higher than typical eucrites. All of these chemical features indicate that the graphic clasts were probably derived from an evolved parent rock. Low‐degree partial melting of the eucritic crust (<10%) is required to generate a melt equilibrated with the REE‐rich rod‐like pyroxene from the graphic clasts. The Si,Ti‐rich regions contain high abundances of silica phases (~52 vol%) and ilmenite (~9 vol%), probably derived from an evolved Si,Ti‐rich rock (dacite). The evolved components observed in NWA 8021 are different from other evolved components observed in howardites and indicate more diverse evolution in the eucrite parent body than previously thought. [ABSTRACT FROM AUTHOR]

Detailed knowledge of the lithospheric structure is essential for a better understanding of the tectonic evolution of the Xing'an‐Mongolian Orogenic Belt (XMOB). We constrained the lithospheric structure across the XMOB by receiver function imaging and shear wave splitting analysis from a dense seismic array. The lithosphere‐asthenosphere boundary (LAB) is coherently imaged in different tectonic blocks. The mid‐lithospheric discontinuity is also identified at ∼75–100 km depth over the deeper LAB (∼110–130 km) beneath the western side of the North‐South Gravity Lineament (NSGL), roughly at the same depth as the LAB beneath the eastern side of the NSGL. The distinct variations in both the lithospheric structure and fast shear‐wave polarization direction across the NSGL are likely caused by different tectonic processes in the two sides, indicating that the NSGL might represent the western boundary influenced by the subduction of the (Paleo‐)Pacific Plate. Lithosphere thinning in the XMOB is evidenced to have been limited mainly to the east of the NSGL. Plain Language Summary: The Xing'an‐Mongolian Orogenic Belt (XMOB) is a key area to study the tectonic evolution of northeast Asia, as it has retained the records for the processes of both the closure of the Paleo‐Asian Ocean and the Mongol‐Okhotsk Ocean and the subduction of the (Paleo‐)Pacific plate. Detailed study of the lithospheric structure is a direct way to unravel the lithospheric dynamic processes in the region. In this study, we present a comprehensive image of the lithospheric structure across the XMOB. The result shows the lithosphere‐asthenosphere boundary with distinct depth variations in different tectonic units of the study area. We also identify a mid‐lithospheric discontinuity at ∼75–100 km depth in the west of the North‐South Gravity Lineament (NSGL). The large variations in lithospheric thickness, seismic anisotropy and crustal structure between the two sides of the NSGL indicate that it might represent a lithospheric boundary in the study region. The eastern side of the NSGL is characterized by a thinned lithosphere of less than 100 km and dominant NW‐SE fast shear wave polarization direction, which reflects considerable lithospheric deformation probably related to the Mesozoic‐Cenozoic subduction of the (Paleo‐)Pacific plate. An integration of our results and geological observations suggests that the area in the west of the NSGL may not have been affected by the (Paleo‐)Pacific subduction. Key Points: The lithosphere‐asthenosphere boundary (LAB) across the Xing'an‐Mongolian Orogenic Belt is coherently imaged with distinct depth variationsThe mid‐lithospheric discontinuity is identified over the deeper LAB beneath the western side of the North‐South Gravity Lineament (NSGL)The NSGL represents the western boundary influenced by the subduction of the (Paleo‐)Pacific Plate [ABSTRACT FROM AUTHOR]

Based on the round‐trip intelligent sounding system, the structure function and spectrum analysis method were carried out to analyze the scale interactions between the small‐scale gravity wave and turbulence in the middle stratosphere. The result showed that the generation of turbulence was closely related to the Kelvin‐Helmholtz (KH) billows. An upscale energy cascade occurred on the spatial scale of KH billows, while a downscale energy cascade occurred on a larger spatial scale (gravity wave scale), which resulted in the breaking of the gravity wave and generation of turbulence. From the multilevel signal measurement, the obvious interactions between turbulence and gravity can be found. The two‐dimensional turbulence that the inverse energy cascade in 2‐D exists simultaneously with a direct enstrophy cascade to the small scales was found, which is considered to be the first‐hand observation result of relevant height. Key Points: The two‐dimensional turbulence is found with bidirectional energy transmissionKH billows are considered to be an important factor in the excitation of turbulenceConvergence and divergence on different scales cause instability within the wave [ABSTRACT FROM AUTHOR]

Fine modeling and fast prediction of regional wind field in the middle and upper atmosphere has always been a difficult problem. We designed a neural operator method to solve this problem. We combine the idea of data assimilation with deep learning method to design a regional wind field operator suitable for near space. The annual Root mean square error of the zonal wind and meridional wind of the operator model at the height of 30 km are 0.903 and 0.881, respectively, which is three times that of ConvLSTM. Moreover, we validate the sparse spatio‐temporal modeling method of regional wind field operator at 20/30/40/50 km altitude. The result shows that the model is mesh‐free, and can get high‐precision modeling of different spatio‐temporal resolutions, multiple regions and arbitrary positions at one time, which lays an foundation for fine regional modeling and rapid utilization of near space. Plain Language Summary: The complex variation mechanism of regional wind fields in near space leads to the difficulty of high‐precision modeling and fast prediction, which seriously affects the design and flight of near space vehicles. In this study, a regional wind field neural operator method has been proposed, which can achieve the fine modeling of the regional wind field in the middle and upper atmosphere. The new method is highly flexible, and can get high‐precision modeling and rapid prediction in different spatial‐temporal resolutions, multiple regions and arbitrary positions. Key Points: The neural operator is first used to study high‐precision spatio‐temporal modeling and rapid prediction of regional wind fields in near spaceThe Root mean square error accuracy of regional wind field operator model is three times that of ConvLSTMThe novel method is suitable for sparse spatio‐temporal modeling at any location with different data resolutions [ABSTRACT FROM AUTHOR]

Abstract: As a proinflammatory cytokine, CD137 (4‐1BB, TNFRSF9) is present in membrane‐bound and soluble forms. Increased expression of CD137 was recently found in T cells in human atherosclerotic plaques. However, the exact role of CD137 in ischemic stroke is not clear. In this study we analyzed the protein levels of soluble CD137 (sCD137) and the expression of CD137 on CD4+ T cells in the peripheral blood of patients with acute atherothrombotic stroke by using the cytometry beads array (CBA) and flow cytometry. Within 24 hours of onset, the stroke patients showed elevated levels of sCD137 (2.7 pg/ml) and CD137 expression on CD4+ T cells (4.9 ± 3.2%) compared with normal controls (1.1 pg/ml, P < 0.01; 1.3 ± 1.0%, P < 0.01). Alterations in CD137 expression may enhance ischemia‐induced inflammatory responses via bidirectional signaling and, consequently, aggravate brain injury in early stages of this disorder. [ABSTRACT FROM AUTHOR]

The permanent magnet brushless motors (PMBLM) are utilised extensively in many high‐performance applications where smoothness of output torque is necessary. When driven with conventional square‐wave current, the PMBLM is hard to make full use of inverter capacity because of short current supply time. Besides, it is hard to produce smooth output torque because the phase inductances slow down the desired step response of the phase current seriously. Although the sinusoidal‐wave current changes continuously, there exists a fixed‐frequency torque ripple for trapezoid back‐electromotive force motor. To solve the problems, two novel current supply methods, called as staircase waveform and parabola‐trapezoid waveform, are proposed in this study. With the same phase current magnitude as square waveform, the staircase waveform can output two times torque with low‐resolution position sensors. The parabola‐trapezoid supply method can further improve the smoothness of doubled output torque by unique parabolic rising and falling edge waveform design, while a high‐resolution position sensor is needed. Simulation and experimental tests of four different current supply methods are given to corroborate the effectiveness of the proposed method in inverter utility and torque ripple reduction. [ABSTRACT FROM AUTHOR]

Background: Aging is accompanied by muscle loss. In older adults with cancer sarcopenia (OACS), systemic inflammation, reduced food intake, and reduced physical activity led to a poor prognosis. This study was to investigate the prognostic ability of the inflammatory Geriatric Nutritional Risk Index (GNRI), which combines patient's inflammation, diet status, and physical activity status to predict overall survival of OACS. Methods: This prospective multi‐center study enrolled 637 OACS, with an average age of 72.78 ± 5.98 years, of which 408 (64.1%) were males. We constructed the Inflammatory Functional Prognostic Index (IFPI) of OACS based on inflammatory GNRI scores, reduced food intake, and reduced physical activity. According to the IFPI, OACS was divided into high‐, moderate‐, and low‐risk groups. Univariate and multivariate survival analyses analyzed the prognostic ability of the clinical parameters. Results: Compared with OACS with a high GNRI score, the 1‐, 3‐, and 5‐year hazard ratios (95% confidence interval) of OACS with a low GNRI score was 1.816 (1.076–3.063), 1.678 (1.118–2.518), and 1.627 (1.101–2.407), respectively. This result was consistent with that of the calibration curve. The subgroup analysis showed that the low GNRI score had a significant positive relation with patients with gastrointestinal cancer (Pinteraction < 0.001). Notably, the survival analysis of IFPI showed that the mortality risk of moderate‐ and high‐risk patients was 1.722‐and 2.509‐fold higher, respectively, than that of low‐risk patients. Conclusion: The GNRI score was a short‐term and long‐term inflammatory prognostic indicator for OACS. The IFPI score could improve patient survival prediction. [ABSTRACT FROM AUTHOR]

Aluminum oxynitride (AlON) ceramics doped with different sintering aids were synthesized by spark plasma sintering process. The microstructures, mechanical, and optical properties of the ceramics were investigated. The results indicate that the optimal amount of sintering aids is 0.06 wt% La2O3 + 0.16 wt% Y2O3 + 0.30 wt% MgO. The addition of La3+ and Mg2+ decreases the rate of grain boundary migration in ceramics, promotes pore elimination, and inhibits grain growth. The addition of Y3+ facilitates liquid‐phase sintering of AlON ceramics. Moreover, the addition of Mg2+ effectively promotes twin formation in the ceramics, which hinders crack propagation and dislocation motion when the ceramics are loaded. Hence, the AlON ceramic doped with 0.06 wt% La2O3 + 0.16 wt% Y2O3 + 0.30 wt% MgO exhibits a relative density of 99.95%, an average grain size of 9.42 μm, and a twin boundary content of 10.3%, which contributes to its excellent mechanical and optical properties. [ABSTRACT FROM AUTHOR]

Reconfigurable intelligent surface (RIS) technology is regarded as one of the important technologies for future 6G mobile communication networks. However, RIS can only passively reflect signals, rather than actively process received signals like the traditional relay. Therefore, a hybrid decode‐and‐forward (DF) relay and RIS‐assisted multiple‐input single‐output (MISO) multiuser downlink communication system is considered to combine the advantages of both. Then the beamforming at the base station (BS), the DF relay, and the phase vector of the RIS elements is jointly designed, aiming at achieving max‐min signal‐to‐interference‐plus‐noise ratio (SINR). Due to the non‐convexity caused by coupling between the beamforming vectors, the optimization problem is split into three semidefinite relaxation (SDR) sub‐problems, and then the alternate optimization method is adopted to solve the non‐convex problem. The numerical results verify the effectiveness and superiority of the proposed optimization algorithm in improving system performance compared with other benchmark schemes. [ABSTRACT FROM AUTHOR]

Background: Immune checkpoint blockade therapy with anti‐programmed cell death (PD)‐1 antibodies provides therapeutic effect for many patients of various cancers but remains inadequate in colorectal cancer (CRC) patients. The present study aims to assess the efficacy of oncolytic adenovirus (OncoAd) in enhancing the anti‐PD‐1 treatment of CRC. Methods: The estimating relative subsets of RNA transcripts algorithm was used for estimating the infiltrated immune cells in melanoma and CRC tissues. The efficacy of OncoAd with anti‐PD‐1 monotherapy was performed in a CT26 CRC mouse model in vivo. Flow cytometric analysis of peripheral blood and tumor tissues determined the difference anti‐tumor immune efficacy of OncoAd with anti‐PD‐1 monotherapy. Results: The Cancer Genome Atlas database indicated that CD8+ T cells and regulatory T cells were significantly elevated in melanoma compared to CRC cohorts. Moreover, intratumor injection of oncolytic adenovirus enhanced T cell infiltration and decreased Treg percentages in the CT26 CRC colorectal cancer mouse model. Combinatorial OncoAd with anti‐PD‐1 antibody treatment markedly enhanced the anti‐tumor efficacy of anti‐PD‐1 by significantly decreasing the tumor volume and reducing tumor growth in a CRC mouse model. To the end, OncoAd treatment increased the CD8/Treg ratio, indicating that OncoAd intratumor injection ameliorate the anti‐tumor immune response of anti‐PD‐1 therapy. Conclusion: The present study elucidates that OncoAd promotes intratumor T cell infiltration and improves anti‐PD‐1 immunotherapy, thereby providing a potent combinatorial therapeutic strategy for CRC. [ABSTRACT FROM AUTHOR]

Summary: Breeding for disease resistance is the most effective strategy to control diseases, particularly with broad‐spectrum disease resistance in many crops. However, knowledge on genes and mechanism of broad‐spectrum resistance and trade‐off between defence and growth in crops is limited. Here, we show that the rice copine genes OsBON1 and OsBON3 are critical suppressors of immunity. Both OsBON1 and OsBON3 changed their protein subcellular localization upon pathogen challenge. Knockdown of OsBON1 and dominant negative mutant of OsBON3 each enhanced resistance to rice bacterial and fungal pathogens with either hemibiotrophic or necrotrophic lifestyles. The defence activation in OsBON1 knockdown mutants was associated with reduced growth, both of which were largely suppressed under high temperature. In contrast, overexpression of OsBON1 or OsBON3 decreased disease resistance and promoted plant growth. However, neither OsBON1 nor OsBON3 could rescue the dwarf phenotype of the Arabidopsis BON1 knockout mutant, suggesting a divergence of the rice and Arabidopsis copine genes. Our study therefore shows that the rice copine genes play a negative role in regulating disease resistance and their expression level and protein location likely have a large impact on the balance between immunity and agronomic traits. [ABSTRACT FROM AUTHOR]

Background: Heteroplasmic mitochondrial 3697G>A mutation has been associated with leber hereditary optic neuropathy (LHON), mitochondrial encephalopathy, lactic acidosis and stroke‐like episodes (MELAS), and LHON/MELAS overlap syndrome. However, homoplasmic m.3697G>A mutation was only found in a family with Leigh syndrome, and the phenotype and pathogenicity of this homoplasmic mutation still need to be investigated in new patients. Methods: The clinical interviews were conducted in 12 individuals from a multiple‐generation inherited family. Mutations were screened through exome next‐generation sequencing and subsequently confirmed by PCR‐restriction fragment length polymorphism. Mitochondrial complex activities and ATP production rate were measured by biochemical analysis. Results: The male offspring with bilateral striatal necrosis (BSN) were characterized by severe spastic dystonia and complete penetrance, while the female offspring presented with mild symptom and low penetrance. All offspring carried homoplasmic mutation of NC_012920.1: m.3697G>A, p.(Gly131Ser). Biochemical analysis revealed an isolated defect of complex I, but the magnitude of the defect was higher in the male patients than that in the female ones. The ATP production rate also exhibited a similar pattern. However, no possible modifier genes on the X chromosome were identified. Conclusion: Homoplasmic m.3697G>A mutation could be associated with BSN, which expanded the clinical spectrum of m.3697G>A. Our preliminary investigations had not found the underlying modifiers to support the double hit hypothesis, while the high level of estrogens in the female patients might exert a potential compensatory effect on mutant cell metabolism. In a maternal inherited family, bilateral striatal necrosis was associated with homoplasmic mitochondrial 3697G>A mutation that resulted in an isolated defect of complex I. Although no possible modifier genes on the X chromosome were found, male offspring presented with severe spastic dystonia and complete penetrance, but the female offspring showed mild symptom and low penetrance. [ABSTRACT FROM AUTHOR]