U–Pb age, trace element and Hf isotope compositions of zircon were analysed for a metasedimentary rock and two amphibolites from the Kongling terrane in the northern part of the Yangtze Craton. The ...zircon shows distinct morphological and chemical characteristics. Most zircon in an amphibolite shows oscillatory zoning, high Th/U and 176Lu/177Hf ratios, high formation temperature, high trace element contents, clear negative Eu anomaly, as well as HREE‐enriched patterns, suggesting that it is igneous. The zircon yields a weighted mean 207Pb/206Pb age of 2857 ± 8 Ma, representing the age of the magmatic protolith. The zircon in the other two samples is metamorphic. It has low Th/U ratios, low trace element concentrations, variable HREE contents (33.8 ≥ LuN≥2213; 14.7 ≤ LuN/SmN ≤ 354) and 176Lu/177Hf ratios (0.000030–0.001168). The data indicate that the zircon formed in the presence of garnet and under upper amphibolite facies conditions. The metamorphic zircon yields a weighted mean 207Pb/206Pb age of 2010 ± 13 Ma. These results combined with previously obtained Palaeoproterozoic metamorphic ages suggest a c. 2.0 Ga Palaeoproterozoic collisional event in the Yangtze Craton, which may result from the assembly of the supercontinent Columbia. The zircon in two samples yields weighted mean two‐stage Hf model (TDM2) ages of 3217 ± 110 and 2943 ± 50 Ma, respectively, indicating that their protoliths were mainly derived from Archean crust.
As the dominant means of energy storage technology today, the widespread deployment of lithium‐ion batteries (LIBs) would inevitably generate countless spent batteries at their end of life. From the ...perspectives of environmental protection and resource sustainability, recycling is a necessary strategy to manage end‐of‐life LIBs. Compared with traditional hydrometallurgical and pyrometallurgical recycling methods, the emerging direct recycling technology, rejuvenating spent electrode materials via a non‐destructive way, has attracted rising attention due to its energy efficient processes along with increased economic return and reduced CO2 footprint. This review investigates the state‐of‐the‐art direct recycling technologies based on effective relithiation through solid‐state, aqueous, eutectic solution and ionic liquid mediums and thoroughly discusses the underlying regeneration mechanism of each method regarding different battery chemistries. It is concluded that direct regeneration can be a more energy‐efficient, cost‐effective, and sustainable way to recycle spent LIBs compared with traditional approaches. Additionally, it is also identified that the direct recycling technology is still in its infancy with several fundamental and technological hurdles such as efficient separation, binder removal and electrolyte recovery. In addressing these remaining challenges, this review proposes an outlook on potential technical avenues to accelerate the development of direct recycling toward industrial applications.
Direct regeneration is considered as an environmentally benign and cost‐effective way to recycle spent lithium‐ion batteries (LIBs). This review comprehensively summarizes the state‐of‐the‐art regeneration technologies for key components separated from spent LIBs and provides critical analysis of existing challenges for different methods. Promising directions to accelerate the development of direct regeneration toward industrial applications are also proposed.
MicroRNAs (miRNA) play an essential role in mammary gland development and lactation. Previous studies in cattle have shown that miR-221 is highly expressed in peak compared with early lactation. ...However, the functions of miR-221 in bovine mammary gland epithelial cells and the mechanisms by which this miRNA affects cell proliferation and milk synthesis remain unclear. We hypothesized that miR-221 targets and modulates the expression of specific genes in the Janus kinase-signal transducer and activator of transcription (JAK-STAT) and phosphatidylinositol 3-kinase-proteinkinase B/mammalian target of rapamycin (PI3K-Akt/mTOR) signaling pathways, which have crucial roles in lactation in cattle. Following transfection of miR-221 into cultured bovine mammary gland epithelial cells, inhibition of cell proliferation and reduced viability of these cells were observed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry analysis. To elucidate the molecular mechanisms of the effects of miR-221 on cell proliferation, we selected potential candidate genes that can be targeted by miR-221 using bioinformatics prediction tools. The dual luciferase assay revealed that STAT5a, STAT3, and IRS1 interact with miR-221 by its direct binding to the 3′-untranslated regions (UTR) of these genes. Subsequent analysis showed that transfection of a miR-221 mimic resulted in significantly decreased expression of STAT5a and IRS1 at both the RNA and protein levels using quantitative real-time PCR and Western blot analyses. Furthermore, expression levels of the downstream genes SOCS3, AKT3, and mTOR that are regulated by STAT5a and IRS1 in the JAK-STAT and PI3K-Akt/mTOR signaling pathways, were also altered after miR-221 transfection. This is the first study to reveal the mechanisms by which miR-221 inhibits mammary gland epithelial cell proliferation by targeting STAT5a and IRS1, key genes in the PI3K-Akt/mTOR and JAK-STAT signaling pathways.
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•Molecular water weakly binds to Co surfaces and it is feasible to desorption from the clean surfaces.•The presence of atomic oxygen has a prominent promotion effect on the ...dissociation of water into hydroxyl, especially on O-covered Co(110) no extra energy is needed to dissociate H2O.•Distinctively, the presence of hydroxyl hinders the dissociation of water molecule.•The analysis of microscopic decomposition behaviors demonstrates that molecular water adsorbs dissociatively with the aid of pre-adsorbed oxygen atom, forming OH radicals chemisorbed on the considered surfaces.
Water adsorption and dissociation on clean and O-covered Co(100), Co(110) and Co(111) surfaces are studied using the density functional theory calculations. The results indicate that molecular water weakly binds to the surfaces and is feasible to desorption from the clean surfaces. Moreover, the pre-adsorption of O atom increases the binding of water to the surfaces, and prominently decreases the activation barriers of water dissociation into OH, especially on Co(110) surface. In contrast, the activation barrier for OH dissociation is slightly affected in the presence of O atom. Overall, this study reveals that O-assisted H2O favorably adsorbs dissociatively, forming OH chemisorbed on the surfaces, which further hinders H2O dissociation, and also illustrates the fact that molecular water dissociation is structure-sensitive on metal surfaces.
•Laser hybrid welding can be applied into railway welded critical aluminum alloys.•Fatigue mechanism was explored by synchrotron radiation X-ray tomography.•Fatigue crack growth span only represents ...a very small portion of the lifetime.•Laser shocking peening can significantly enhance the performance against fatigue.
The fatigue behavior of laser hybrid welded 7000 series aluminum alloys with high Zn was investigated by electron backscattered diffraction, transmission electron microscopy, energy-dispersive spectroscopy, basic mechanical tests, fatigue cracking rate, synchrotron radiation X-ray computed micro-tomography, high-cycle fatigue and residual stress-based fatigue crack growth simulation. The results show that hybrid laser welding process leads to essential changes of microstructure and micro-hardness. It has also been found that the fatigue performance of grinded laser shock treated joints is significantly improved compared with that of as-received welded joints. Besides, hybrid laser welded joints present slightly higher fatigue crack propagation rate than base metal under load ratios of R=0.1 and 0.3, which can be intrinsically attributed to the higher crackability of weld and inner porosity in terms of grain disorientation and three-dimensional gas pores. Based on finite element modeling, a new fatigue crack propagation life model is established by incorporating weld residual stress, and the predictions are in good agreement with experimental results under different welding parameters.
Summary
Sleep and daytime movement behaviours occur co‐dependently with each other within a finite 24 h day. Sleep parameters other than sleep duration, such as social jetlag and chronotype, have ...been linked to health problems and unhealthy behaviours among children and adolescents. Given the increasing number of studies examining sleep timing/chronotype and weight‐related behaviours, including physical activity and sedentary behaviour, in the past decade, this systematic review and meta‐analysis collated and evaluated the evidence on the relationships of social jetlag and chronotype with physical activity and sedentary behaviour among children and adolescents aged 3–17 years. Seven databases were searched on 16 March 2022, and 52 studies were identified as eligible for inclusion, 47 of which were suitable for the meta‐analysis. A positive association was found between social jetlag and screen media use (r = 0.14, 95% CI: 0.04–0.24; I2 = 96%; p = 0.008). The morning chronotype was associated with a higher level of physical activity and a lower level of sedentary behaviour than the evening chronotype. No relationship was found between social jetlag and physical activity. The magnitude of heterogeneity among the included studies was high. Further experimental studies are urgently required to understand how circadian preference or misalignment affects activity behaviours. Interventions to promote an active lifestyle in young populations should consider their circadian preference, especially among individuals with the evening chronotype.
Magnetic fields have an important role in the evolution of interstellar medium and star formation
. As the only direct probe of interstellar field strength, credible Zeeman measurements remain sparse ...owing to the lack of suitable Zeeman probes, particularly for cold, molecular gas
. Here we report the detection of a magnetic field of +3.8 ± 0.3 microgauss through the H I narrow self-absorption (HINSA)
towards L1544
-a well-studied prototypical prestellar core in an early transition between starless and protostellar phases
characterized by a high central number density
and a low central temperature
. A combined analysis of the Zeeman measurements of quasar H I absorption, H I emission, OH emission and HINSA reveals a coherent magnetic field from the atomic cold neutral medium (CNM) to the molecular envelope. The molecular envelope traced by the HINSA is found to be magnetically supercritical, with a field strength comparable to that of the surrounding diffuse, magnetically subcritical CNM despite a large increase in density. The reduction of the magnetic flux relative to the mass, which is necessary for star formation, thus seems to have already happened during the transition from the diffuse CNM to the molecular gas traced by the HINSA. This is earlier than envisioned in the classical picture where magnetically supercritical cores capable of collapsing into stars form out of magnetically subcritical envelopes
.
The molecular characterization of cytogenetic abnormalities has not only provided insights into the mechanisms of leukemogenesis but also led to the establishment of new treatment strategies ...targeting these abnormalities and thereby further improve the prognosis of patients. We analyzed the prognosis of 1091 Chinese patients with newly diagnosed acute lymphoblastic leukemia (ALL) and explored the prognostic impacts of a large number of cytogenetic/molecular abnormalities. It was demonstrated that, in both B- and T-ALL settings, the prognosis was negatively correlated to the age as reported to date. For childhood T-ALL patients, it was also documented that the HOX11 expression represented a favorable prognostic factor as it was in adult ones. We identified CRLF2 overexpression as an intermediate-risk marker and Ik6 variant of IKZF1 gene as a high-risk one when stratifying pediatric B-ALL cases according to cytogenetic/molecular risks. We also found that Ik6 variant and CRLF2 overexpression had an important role in dictating the prognosis of Ph-negative patients, which may be useful markers in guiding the treatment of ALL in the future, with tyrosine kinase inhibitors on the other hand reversing the fate of Ph-positive ALL patients.
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