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Strong steels are primarily fabricated by introducing spatial obstacles (e.g., stacking faults and precipitates) that inhibit dislocation slips under stress to achieve high strength. However, for most low-carbon steels, such obstacles are difficult to form mainly because the martensitic transition is kinetically unfavorable by conventional methods, which precludes the attainment of high-strength materials in these steels with low solute contents. Here, we report an innovative high-pressure preparation of martensitic pure Fe with involving nano-effect, which leads to the formation of ultrastrong bulk iron with exceptionally high yield strength, ultimate strength, and hardness of 2.9 GPa, 3.7 GPa, and 9.0 GPa, respectively, exceeding those of high-speed steels. Such extraordinary mechanical properties are closely attributed to its high-density martensites with unique multiscale hierarchical structures formed due to complex phase transitions under pressure.
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Self-incompatibility (SI) is a widespread genetically determined system in flowering plants that prevents self-fertilization to promote gene flow and limit inbreeding. S-RNase-based SI is characterized by the arrest of pollen tube growth through the pistil. Arrested pollen tubes show disrupted polarized growth and swollen tips, but the underlying molecular mechanism is largely unknown. Here, we demonstrate that the swelling at the tips of incompatible pollen tubes in pear (Pyrus bretschneideri [Pbr]) is mediated by the SI-induced acetylation of the soluble inorganic pyrophosphatase (PPA) PbrPPA5. Acetylation at Lys-42 of PbrPPA5 by the acetyltransferase GCN5-related N-acetyltransferase 1 (GNAT1) drives accumulation of PbrPPA5 in the nucleus, where it binds to the transcription factor PbrbZIP77, forming a transcriptional repression complex that inhibits the expression of the pectin methylesterase (PME) gene PbrPME44. The function of PbrPPA5 as a transcriptional repressor does not require its PPA activity. Downregulating PbrPME44 resulted in increased levels of methyl-esterified pectins in growing pollen tubes, leading to swelling at their tips. These observations suggest a mechanism for PbrPPA5-driven swelling at the tips of pollen tubes during the SI response. The targets of PbrPPA5 include genes encoding cell wall-modifying enzymes, which are essential for building a continuous sustainable mechanical structure for pollen tube growth.
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Tubo Polínico , Pyrus , Ribonucleases/metabolismo , Pirofosfatase Inorgânica/genética , Pirofosfatase Inorgânica/metabolismo , Acetilação , Pyrus/metabolismoRESUMO
Single-atom Fenton-like catalysis has attracted significant attention, yet the quest for controllable synthesis of single-atom catalysts (SACs) with modulation of electron configuration is driven by the current disadvantages of poor activity, low selectivity, narrow pH range, and ambiguous structure-performance relationship. Herein, we devised an innovative strategy, the slow-release synthesis, to fabricate superior Cu SACs by facilitating the dynamic equilibrium between metal precursor supply and anchoring site formation. In this strategy, the dynamics of anchoring site formation, metal precursor release, and their binding reaction kinetics were regulated. Bolstered by harmoniously aligned dynamics, the selective and specific monatomic binding reactions were ensured to refine controllable SACs synthesis with well-defined structure-reactivity relationship. A copious quantity of monatomic dispersed metal became deposited on the C3N4/montmorillonite (MMT) interface and surface with accessible exposure due to the convenient mass transfer within ordered MMT. The slow-release effect facilitated the generation of targeted high-quality sites by equilibrating the supply and demand of the metal precursor and anchoring site and improved the utilization ratio of metal precursors. An excellent Fenton-like reactivity for contaminant degradation was achieved by the Cu1/C3N4/MMT with diminished toxic Cu liberation. Also, the selective ·OH-mediated reaction mechanism was elucidated. Our findings provide a strategy for regulating the intractable anchoring events and optimizing the microenvironment of the monatomic metal center to synthesize superior SACs.
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Expression of macrophage receptor with collagenous structure (MARCO) by tumor-associated macrophages is associated with poor prognosis of multiple types of cancer. In this article, we report that cancer cells (e.g., breast cancer and glioblastoma cell lines) can upregulate surface MARCO expression on human macrophages not only via IL-6-induced STAT3 activation but also via sphingosine-1-phosphate receptor (S1PR)-mediated IL-6 and IL-10 expression followed by STAT3 activation. We further found that MARCO ligation induces activation of the MEK/ERK/p90RSK/CREB signaling cascade, leading to IL-10 expression followed by STAT3-dependent PD-L1 upregulation. Such MARCO-induced macrophage polarization is accompanied by increased expression of PPARG, IRF4, IDO1, CCL17, and CCL22. Ligation of surface MARCO can thus result in decreased T cell responses mainly by reduction of their proliferation. Taken together, cancer cell-induced MARCO expression and its intrinsic regulatory function within macrophages are, to our knowledge, new aspects of cancer immune evasion mechanisms that need to be further studied in the future.
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Interleucina-10 , Neoplasias , Humanos , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Macrófagos , Neoplasias/metabolismo , Receptores Imunológicos , Receptores Depuradores/metabolismoRESUMO
Gametophytic self-incompatibility (GSI) has been widely studied in flowering plants, but studies of the mechanisms underlying pollen tube growth arrest by self S-RNase in GSI species are limited. In the present study, two leucine-rich repeat extensin genes in pear (Pyrus bretschneideri), PbLRXA2.1 and PbLRXA2.2, were identified based on transcriptome and quantitative real-time PCR analyses. The expression levels of these two LRX genes were significantly higher in the pollen grains and pollen tubes of the self-compatible cultivar 'Jinzhui' (harboring a spontaneous bud mutation) than in those of the self-incompatible cultivar 'Yali'. Both PbLRXA2.1 and PbLRXA2.2 stimulated pollen tube growth and attenuated the inhibitory effects of self S-RNase on pollen tube growth by stabilizing the actin cytoskeleton and enhancing cell wall integrity. These results indicate that abnormal expression of PbLRXA2.1 and PbLRXA2.2 is involved in the loss of self-incompatibility in 'Jinzhui'. The PbLRXA2.1 and PbLRXA2.2 promoters were directly bound by the ABRE-binding factor PbABF.D.2. Knockdown of PbABF.D.2 decreased PbLRXA2.1 and PbLRXA2.2 expression and inhibited pollen tube growth. Notably, the expression of PbLRXA2.1, PbLRXA2.2, and PbABF.D.2 was repressed by self S-RNase, suggesting that self S-RNase can arrest pollen tube growth by restricting the PbABF.D.2-PbLRXA2.1/PbLRXA2.2 signal cascade. These results provide novel insight into pollen tube growth arrest by self S-RNase.
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Pyrus , Ribonucleases , Ribonucleases/genética , Ribonucleases/metabolismo , Tubo Polínico/metabolismo , Pyrus/genética , Pyrus/metabolismo , Pólen/genética , Citoesqueleto de Actina/metabolismoRESUMO
The potential universality of chemical transformation principles makes it a powerful tool for nanocrystal (NC) synthesis. An example is the nanoscale Kirkendall effect, which serves as a guideline for the construction of hollow structures with different properties compared to their solid counterparts. However, even this general process is still limited in material scope, structural complexity, and, in particular, transformations beyond the conventional solid-to-hollow process. We demonstrate in this work an extension of the Kirkendall effect that drives reversible structural and phase transformations between metastable metal chalcogenides (MCs) and metal phosphides (MPs). Starting from Ni3S4/Cu1.94S NCs as the initial frameworks, ligand-regulated sequential extractions and diffusion of host/guest (S2-/P3-) anions between Ni3S4/Cu1.94S and Ni2P/Cu3P phases enable solid-to-hollow-to-solid structural motif evolution while retaining the overall morphology of the NC. An in-depth mechanistic study reveals that the transformation between metastable MCs and MPs occurs through a combination of ligand-dependent kinetic control and anion mixing-induced thermodynamic control. This strategy provides a robust platform for creating a library of reconfigurable NCs with tunable compositions, structures, and interfaces.
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BACKGROUND: Relict species are important for enhancing the understanding of modern biogeographic distribution patterns. Although both geological and climatic changes since the Cenozoic have affected the relict flora in East Asia, the contributions of geographical processes remain unclear. In this study, we employed restriction-site associated DNA sequencing (RAD-seq) and shallow genome sequencing data, in conjunction with ecological niche modeling (ENM), to investigate the spatial genetic patterns and population differentiation history of the relict species Rehderodendron kwangtungense Chun. RESULTS: A total of 138 individuals from 16 populations were collected, largely covering the natural distribution of R. kwangtungense. The genetic diversity within the R. kwangtungense populations was extremely low (HO = 0.048 ± 0.019; HE = 0.033 ± 0.011). Mantel tests revealed isolation-by-distance pattern (R2 = 0.38, P < 0.001), and AMOVA analysis showed that the genetic variation of R. kwangtungense occurs mainly between populations (86.88%, K = 7). Between 23 and 21 Ma, R. kwangtungense underwent a period of rapid differentiation that coincided with the rise of the Himalayas and the establishment of the East Asian monsoon. According to ENM and population demographic history, the suitable area and effective population size of R. kwangtungense decreased sharply during the glacial period and expanded after the last glacial maximum (LGM). CONCLUSION: Our study shows that the distribution pattern of southern China mountain relict flora may have developed during the panplain stage between the middle Oligocene and the early Miocene. Then, the flora later fragmented under the force of orogenesis, including intermittent uplift during the Cenozoic Himalayan orogeny and the formation of abundant rainfall associated with the East Asian monsoon. The findings emphasized the predominant role of geographical processes in shaping relict plant distribution patterns.
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Mudança Climática , Variação Genética , Filogeografia , Ásia Oriental , Dispersão Vegetal , Análise de Sequência de DNARESUMO
Lymph node metastasis (LNM) is a significant barrier to the prognosis of patients with gastric cancer (GC). Helicobacter pylori (H. pylori)-positive GC patients experience a higher rate of LNM than H. pylori-negative GC patients. However, the underlying mechanism remains unclear. Based on the findings of this study, H. pylori-positive GC patients have greater lymphangiogenesis and lymph node immunosuppression than H. pylori-negative GC patients. In addition, miR-1246 is overexpressed in the plasma small extracellular vesicles (sEVs) of H. pylori-positive GC patients, indicating a poor prognosis. Functionally, sEVs derived from GC cells infected with H. pylori deliver miR-1246 to lymphatic endothelial cells (LECs) and promote lymphangiogenesis and lymphatic remodeling. Mechanistically, miR-1246 suppresses GSK3ß expression and promotes ß-Catenin and downstream MMP7 expression in LECs. miR-1246 also stabilizes programmed death ligand-1 (PD-L1) by suppressing GSK3ß and induces the apoptosis of CD8+ T cells. Overall, miR-1246 in plasma sEVs may be a novel biomarker and therapeutic target in GC-LNM.
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Vesículas Extracelulares , Helicobacter pylori , MicroRNAs , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/metabolismo , Linfangiogênese , Células Endoteliais/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Glicogênio Sintase Quinase 3 beta , MicroRNAs/genética , Vesículas Extracelulares/metabolismoRESUMO
Limited by the strong oxidation environment and sluggish reconstruction process in oxygen evolution reaction (OER), designing rapid self-reconstruction with high activity and stability electrocatalysts is crucial to promoting anion exchange membrane (AEM) water electrolyzer. Herein, trace Fe/S-modified Ni oxyhydroxide (Fe/S-NiOOH/NF) nanowires are constructed via a simple in situ electrochemical oxidation strategy based on precipitation-dissolution equilibrium. In situ characterization techniques reveal that the successful introduction of Fe and S leads to lattice disorder and boosts favorable hydroxyl capture, accelerating the formation of highly active γ-NiOOH. The Density Functional Theory (DFT) calculations have also verified that the incorporation of Fe and S optimizes the electrons redistribution and the d-band center, decreasing the energy barrier of the rate-determining step (*Oâ*OOH). Benefited from the unique electronic structure and intermediate adsorption, the Fe/S-NiOOH/NF catalyst only requires the overpotential of 345 mV to reach the industrial current density of 1000 mA cm-2 for 120 h. Meanwhile, assembled AEM water electrolyzer (Fe/S-NiOOH//Pt/C-60 °C) can deliver 1000 mA cm-2 at a cell voltage of 2.24 V, operating at the average energy efficiency of 71% for 100 h. In summary, this work presents a rapid self-reconstruction strategy for high-performance AEM electrocatalysts for future hydrogen economy.
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Osteoporotic bone defects, a severe complication of osteoporosis, are distinguished by a delayed bone healing process and poor repair quality. While bone marrow-derived mesenchymal stem cells (BMMSCs) are the primary origin of bone-forming osteoblasts, their mitochondrial function is impaired, leading to inadequate bone regeneration in osteoporotic patients. Melatonin is well-known for its antioxidant properties and regulation on bone metabolism. The present study postulated that melatonin has the potential to enhance the repair of osteoporotic bone defects by restoring the mitochondrial function of BMMSCs. In vitro administration of melatonin at varying concentrations (0.01, 1, and 100 µM) demonstrated a significant dose-dependent improvement in the mitochondrial function of BMMSCs obtained from ovariectomized rats (OVX-BMMSCs), as indicated by an elevation in mitochondrial membrane potential, adenosine triphosphate synthesis and expression of mitochondrial respiratory chain factors. Melatonin reduced the level of mitochondrial superoxide by activating the silent information regulator type 1 (SIRT1) and its downstream antioxidant enzymes, particularly superoxide dismutase 2 (SOD2). The protective effects of melatonin were found to be nullified upon silencing of Sirt1 or Sod2, underscoring the crucial role of the SIRT1-SOD2 axis in the melatonin-induced enhancement of mitochondrial energy metabolism in OVX-BMMSCs. To achieve a sustained and localized release of melatonin, silk fibroin scaffolds loaded with melatonin (SF@MT) were fabricated. The study involved the surgical creation of bilateral femur defects in OVX rats, followed by the implantation of SF@MT scaffolds. The results indicated that the application of melatonin partially restored the mitochondrial energy metabolism and osteogenic differentiation of OVX-BMMSCs by reinstating mitochondrial redox homeostasis. These findings suggest that the localized administration of melatonin through bone implants holds potential as a therapeutic approach for addressing osteoporotic bone defects.
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Melatonina , Células-Tronco Mesenquimais , Osteoporose , Humanos , Ratos , Animais , Osteogênese , Melatonina/metabolismo , Sirtuína 1/metabolismo , Antioxidantes/uso terapêutico , Medula Óssea/metabolismo , Osteoporose/tratamento farmacológico , Diferenciação Celular , Mitocôndrias/metabolismo , Células CultivadasRESUMO
BACKGROUND: Congenital agenesis of internal carotid artery (ICA) is a rare cerebrovascular variation entity. Most cases of congenital ICA agenesis are asymptomatic and discovered incidentally. Congenital ICA agenesis presenting as ischemic stroke is even rare. CASE PRESENTATION: An 80-year-old male patient was admitted to our hospital due to sudden dysarthria and left limb weakness for 3.5 h. Based on emergency physical examination and head computed tomography (CT) scan results, acute ischemic stroke (AIS) of right cerebral hemisphere was suspected. Following intravenous thrombolysis with recombinant tissue plasminogen activator, right congenital agenesis of ICA was confirmed by CT and digital subtraction angiography. Additionally, there was a severe right vertebral artery ostial (VAO) stenosis. After ruling out common causes of AIS such as haematological diseases, arterial dissection, organic heart disease, immunological abnormality and underlying possible malignancies, we hypothesize that the severe stenosis of the right VAO may have contributed to the development of AIS in this case. CONCLUSIONS: We present a case of right congenital ICA agenesis in which severe stenosis of the right VAO may have played a role in the development of AIS. This case underscores a rare scenario where a lesion in the posterior circulation leads to an infarction in the anterior circulation in the setting of congenital ICA agenesis.
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Artéria Carótida Interna , AVC Isquêmico , Humanos , Masculino , Idoso de 80 Anos ou mais , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/etiologia , AVC Isquêmico/complicações , Artéria Carótida Interna/anormalidades , Artéria Carótida Interna/diagnóstico por imagem , Insuficiência Vertebrobasilar/diagnóstico por imagem , Insuficiência Vertebrobasilar/complicaçõesRESUMO
BACKGROUND: It is widely accepted that glaucoma-induced oxidative stress expedites cataracts' process. Therefore, we examined the effects of apelin-13 against oxidative stress-induced damage in human lens epithelial cells (HLECs) and investigated the potential pathogenic mechanism of acute primary angle-closure glaucoma. METHODS: This experiment included five groups: control, H2O2, apelin-13 + H2O2, ML221 + H2O2, and apelin-13 + ML221 + H2O2. ML221 was employed in rescue experiments as an APJ antagonist. HLECs were pretreated with or without apelin-13 and subsequently exposed to H2O2. HLECs' viability was assessed by CCK8. Cell apoptosis was determined using Annexin V-FITC/PI staining. The mitochondrial membrane potential was assessed by fluorescent probe JC-1. Intracellular G6PD activity, NADPH/NADP+, and GSH/GSSG ratios were detected to assess the cells' oxidative damage. RESULT: Apelin-13 reversed the H2O2-induced decrease in cell viability. The increased expression of G6PD and GLTU1, the G6PD, GSH/GSSG and NADPH/NADP + levels showed that apelin-13 can mitigate the H2O2-induced inhibition of the pentose phosphate pathway and dysregulation of cell redox status in the apelin-13 + H2O2 group compared with the H2O2 group. In H2O2-treated HLECs, apelin-13 can mitigate cell apoptosis, promote Bcl-2 expression, and suppress the Bax and Caspase-3 expression. In addition, H2O2 substantially reduced the mitochondrial membrane potential in HLECs, which was reversed by apelin-13. Notably, the inhibition of APJ intensified oxidative damage in H2O2-induced HLECs, demonstrating that the effects of apelin-13 were hindered by ML221. CONCLUTIONS: Apelin-13 reduced oxidative damage and apoptosis in HLECs through APJ. These results demonstrate that apelin-13 can be employed as a potential drug for glaucoma with cataracts to delay the progression of cataracts.
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Apoptose , Sobrevivência Celular , Células Epiteliais , Peróxido de Hidrogênio , Peptídeos e Proteínas de Sinalização Intercelular , Cristalino , Potencial da Membrana Mitocondrial , Estresse Oxidativo , Estresse Oxidativo/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Humanos , Cristalino/efeitos dos fármacos , Cristalino/metabolismo , Cristalino/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Peróxido de Hidrogênio/toxicidade , Peróxido de Hidrogênio/farmacologia , Células CultivadasRESUMO
Sub-1-nm structures are attractive for diverse applications owing to their unique properties compared to those of conventional nanomaterials. Transition-metal hydroxides are promising catalysts for oxygen evolution reaction (OER), yet there remains difficulty in directly fabricating these materials within the sub-1-nm regime, and the realization of their composition and phase tuning is even more challenging. Here we define a binary-soft-template-mediated colloidal synthesis of phase-selective Ni(OH)2 ultrathin nanosheets (UNSs) with 0.9 nm thickness induced by Mn incorporation. The synergistic interplay between binary components of the soft template is crucial to their formation. The unsaturated coordination environment and favorable electronic structures of these UNSs, together with in situ phase transition and active site evolution confined by the ultrathin framework, enable efficient and robust OER electrocatalysis. They exhibit a low overpotential of 309 mV at 100 mA cm-2 as well as remarkable long-term stability, representing one of the most high-performance noble-metal-free catalysts.
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Postsynthetic chemical transformation provides a powerful platform for creating heteronanostructures (HNs) with well-defined materials and interfaces that generate synergy or enhancement. However, it remains a synthetic bottleneck for the precise construction of HNs with increased degrees of complexity and more elaborate functions in a predictable manner. Herein, we define a general transformative protocol for metal phosphosulfide HNs based on tunable hexagonal Cu1.81S frameworks with corner-, edge- and face-controlled growth of Co2P domains. The region-controlled Cu1.81S-Co2P framework interfaces can serve as "kinetic barriers" in mediating the direction and rate between P and S anion exchange reactions, thus leading to a family of morphology and phase designed Cu3P1-xSx-Co2P HNs with hollow (branched, dotted and crown), porous and core-shell architectures. This study reveals the internal transformation mechanism between metal sulfide and phosphide nanocrystals, and opens up a new way for the rational synthesis of metastable HNs that are otherwise inaccessible.
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Hydraulic oil leaks during mechanical maintenance, resulting in flushing wastewater contaminated with dispersed nano-oil droplets. In this study, 75 mg L-1 of polysilicate aluminum ferric (PSAF) was stirred at 350 rpm and the optimal chemical oxygen demand (COD) removal was 71%. The increase of PSAF led to more hydrolysis of Fe, and 1,175 cm-1 hydroxyl bridged with negative oil droplets. At the same molar concentration, PSAF hydrolyzes cationic metals more rapidly than polymeric aluminum chloride (PAC). PSAF forms flocs of smaller complex structures with greater bridging. The Al-O and Si-O peaks occurred at 611 and 1,138 cm-1, indicating the formation of Si-O-Fe and Si-O-Al bonds on the flocs surface. Higher stirring speeds did not change the free energy of the flocs surface γTot, mainly because the decrease in the van der Waals force (γLW) offset the increase of Lewis acid-base force (γAB). Preserving the non-polar surface, in summary, owing to its bridging abilities and affinity for non-polar surfaces, PSAF demonstrates superior efficiency over PAC in capturing and removing oil droplets.
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Compostos Férricos , Compostos Férricos/química , Alumínio/química , Óleos/química , Propriedades de Superfície , Purificação da Água/métodos , Eliminação de Resíduos Líquidos/métodosRESUMO
Rare earth (RE) elements are attractive for spin-magnetic modulation due to their unique 4 f electron configuration and strong orbital couplings. Alloying RE with conventional 3d transition-metal (TM) is promising for the fabrication of advanced spin catalysts yet remains much difficulties in preparation, which leads to the mysteries of spin-magnetic effect between RE and 3d TM on catalysis. Here we define a solid-phase synthetic protocol for creating RE-3d TM-noble metal integrated intraparticle heterostructured nanoalloys (IHAs) with distinct Gd and Co interface within the entire Rh framework, denoted as RhCo-RhGd IHAs. They exhibit interface-triggered antiferromagnetic interaction, which can induce electron redistribution and regulate spin polarization. Theoretical calculations further reveal that active sites around the heterointerface with weakened spin polarization optimize the adsorption and dissociation of H2O, thus promoting alkaline hydrogen evolution catalysis. The RhCo-RhGd IHAs show a small overpotential of 11.3â mV at 10â mA cm-2, as well as remarkable long-term stability, far superior to previously reported Rh-based catalysts.
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Nanomaterial-based in vivo tumor imaging and therapy have attracted extensive attention; however, they suffer from the unintelligent "always ON" or single-parameter responsive signal output, substantial off-target effects, and high cost. Therefore, achieving in vivo easy-to-read tumor imaging and precise therapy in a multi-parameter responsive and intelligent manner remains challenging. Herein, an intelligent DNA nanoreactor (iDNR) was constructed following the "AND" Boolean logic algorithm to address these issues. iDNR-mediated in situ deposition of photothermal substance polydopamine (PDA) can only be satisfied in tumor tissues with abundant membrane protein biomarkers "AND" hydrogen peroxide (H2 O2 ). Therefore, intelligent temperature-based in vivo easy-to-read tumor imaging is realized without expensive instrumentation, and its diagnostic performance matches with that of flow cytometry, and photoacoustic imaging. Moreover, precise photothermal therapy (PTT) of tumors could be achieved via intelligent heating of tumor tissues. The precise PTT of primary tumors in combination with immune checkpoint blockade (ICB) therapy suppresses the growth of distant tumors and inhibits tumor recurrence. Therefore, highly programmable iDNR is a powerful tool for intelligent biomedical applications.
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Nanopartículas , Nanoestruturas , Neoplasias , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Neoplasias/patologia , Fototerapia/métodos , Nanotecnologia , Linhagem Celular Tumoral , Microambiente TumoralRESUMO
The surge in lithium-ion batteries has heightened concerns regarding metal resource depletion and the environmental impact of spent batteries. Battery recycling has become paramount globally, but conventional techniques, while effective at extracting transition metals like cobalt and nickel from cathodes, often overlook widely used spent LiFePO4 due to its abundant and low-cost iron content. Direct regeneration, a promising approach for restoring deteriorated cathodes, is hindered by practicality and cost issues despite successful methods like solid-state sintering. Hence, a smart prelithiation separator based on surface-engineered sacrificial lithium agents is proposed. Benefiting from the synergistic anionic and cationic redox, the prelithiation separator can intelligently release or intake active lithium via voltage regulation. The staged lithium replenishment strategy was implemented, successfully restoring spent LiFePO4's capacity to 163.7â mAh g-1 and a doubled life. Simultaneously, the separator can absorb excess active lithium up to approximately 600â mAh g-1 below 2.5â V to prevent over-lithiation of the cathode This innovative, straightforward, and cost-effective strategy paves the way for the direct regeneration of spent batteries, expanding the possibilities in the realm of lithium-ion battery recycling.
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Hard and superconducting materials play significant roles in their respective application areas and are also crucial research fields in condensed matter physics. Materials with the key properties of both hard and superconducting properties could lead to technology development, but it is also full of challenges. Herein, we report the synthesis of high-quality metastable W3P single crystals with superconductivity and excellent mechanical properties. The synergistic effect of temperature and pressure was effective in suppressing further decomposition of metastable W3P as-synthesized by our synthesis technique (high-pressure and high-temperature method). The transport and magnetic measurements indicate that W3P is a typical type-II BCS superconductor, displaying a superconducting transition temperature of 5.9 K and an impressive critical magnetic field of 4.35 T. Theory calculations reveal a metallic property in W3P, and the phonon modes of the vibration of W atoms are important for electron-phonon interaction. Meanwhile, W3P shows excellent mechanical properties with a high fracture toughness of 8 MPa m1/2 and an impressive asymptotic hardness of 22 GPa, which is currently reported as being the hardest among transition metal phosphides. It opens up a new class of advanced materials that combine excellent mechanical properties with superconductivity.
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Nucleic acid aptamer-based nanomicelles have great potential for nanomedicine and nanotechnology applications. However, amphiphilic aptamer micelles are known to be inherently unstable upon interaction with cell membranes in the physiological environment, thus potentially compromising their specific targeting against cancer cells. This flaw is addressed in the present work which reports a superstable micellar nanodelivery system as an amphiphilic copolymer self-assembled micelle composed of nucleic acid aptamer and polyvalent hydrophobic poly(maleic anhydride-alt-1-octadecene) (C18PMH). Using Ce6 as a drug model, these C18-aptamer micelles exhibit efficient tumor-targeting and -binding ability, facilitating the entry of Ce6 into targeted cells for photodynamic therapy. In addition, they can be loaded with other hydrophobic drugs and still demonstrate favorable therapeutic effects. As such, these C18-aptamer micelles can serve as a universal platform for loading multiple drugs, providing a safer and more effective solution for treating cancer.