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The instability of carbonate electrolyte with metallic Li greatly limits its application in high-voltage Li metal batteries. Here, a "salt-in-salt" strategy is applied to boost the LiNO3 solubility in the carbonate electrolyte with Mg(TFSI)2 carrier, which enables the inorganic-rich solid electrolyte interphase (SEI) for excellent Li metal anode performance and also maintains the cathode stability. In the designed electrolyte, both NO3 - and PF6 - anions participate in the Li+ -solvent complexes, thus promoting the formation of inorganic-rich SEI. Our designed electrolyte has achieved a superior Li CE of 99.7 %, enabling the high-loading NCM811||Li (4.5â mAh cm-2 ) full cell with N/P ratio of 1.92 to achieve 84.6 % capacity retention after 200â cycles. The enhancement of LiNO3 solubility by divalent salts is universal, which will also inspire the electrolyte design for other metal batteries.
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LiNix Coy Mnz O2 (x+y+z=1)||graphite lithium-ion battery (LIB) chemistry promises practical applications. However, its low-temperature (≤ -20 °C) performance is poor because the increased resistance encountered by Li+ transport in and across the bulk electrolytes and the electrolyte/electrode interphases induces capacity loss and battery failures. Though tremendous efforts have been made, there is still no effective way to reduce the charge transfer resistance (Rct ) which dominates low-temperature LIBs performance. Herein, we propose a strategy of using low-polarity-solvent electrolytes which have weak interactions between the solvents and the Li+ to reduce Rct , achieving facile Li+ transport at sub-zero temperatures. The exemplary electrolyte enables LiNi0.8 Mn0.1 Co0.1 O2 ||graphite cells to deliver a capacity of ≈113â mAh g-1 (98 % full-cell capacity) at 25 °C and to remain 82 % of their room-temperature capacity at -20 °C without lithium plating at 1/3C. They also retain 84 % of their capacity at -30 °C and 78 % of their capacity at -40 °C and show stable cycling at 50 °C.
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Layered double hydroxides (LDHs) have been considered as promising electrodes for supercapacitors due to their adjustable composition, designable function and superior high theoretic capacity. However, their experimental specific capacity is significantly lower than the theoretical value due to their small interlayer spacing. Therefore, obtaining large interlayer spacing through the intercalation of large-sized anions is an important means to improve capacity performance. Herein, a metal organic framework derived cobalt-nickel layered double hydroxide hollowcage intercalated with different concentrations of 1,4-benzenedicarboxylic acid (H2 BDC) through in-situ cationic etching and organic ligand intercalation method is designed and fabricated. The superior specific capacity and excellent rate performance are benefit from the large specific surface area of the hollow structure and increasing interlayer spacing of LDH after H2 BDC intercalation. The sample with the largest layer spacing displays a maximum specific capacity of 229 mA h g-1 at 1 A g-1 . In addition, the hybrid supercapacitor assembled from the sample with the largest layer spacing and active carbon electrode has a maximum specific capacity of 158 mA h g-1 at 1 A g-1 ; the energy density is as high as 126.4 W h kg-1 at 800 W kg-1 and good cycle stability.
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Identifying new and economical means to utilize diverse lignocellulosic biomass is an urgent task. Ganoderma lucidum is a well-known edible and medicinal basidiomycete with an excellent ability to degrade a wide range of cellulosic biomass, and its nutrient use efficiency is closely related to the activity of extracellular cellulase. Intracellular nicotinamide adenine dinucleotide (NAD+) biosynthesis is controlled in response to nutritional status, and NAD+ is an essential metabolite involved in diverse cellular processes. Nicotinamide mononucleotide adenylyltransferase (NMNAT) is a common enzyme in three NAD+ synthesis pathways. In this study, a homologous gene of nmnat was cloned from G. lucidum and two G. lucidum overexpression strains, OE::nmnat4 and OE::nmnat19, were constructed using an Agrobacterium tumefaciens-mediated transformation method. The G. lucidum nmnat overexpression strains showed obviously increased colony growth on different carbon sources, and intracellular Ca2+ concentrations in the G. lucidum OE::nmnat4 and OE::nmnat19 strains were increased by 2.04- and 2.30-fold, respectively, compared with those in the wild-type (WT) strains. In the G. lucidum OE::nmnat4 and OE::nmnat19 strains, endo-ß-glucanase (CMCase) activity increased by approximately 2.8- and 3-fold, while ß-glucosidase (pNPGase) activity increased by approximately 1.9- and 2.1-fold, respectively, compared with the activity in the WT strains. Furthermore, overexpression of NAD+ synthesis pathways was found to elicit cellulase production by increasing the intracellular Ca2+ concentration. In summary, this study is the first to demonstrate that increased intracellular NAD+ contents through overexpression of the nmnat gene of NAD+ synthesis pathways may increase cellulase production by increasing intracellular Ca2+ concentrations in G. lucidum. KEY POINTS: ⢠The concentration of NAD+influences cellulase production in G. lucidum. ⢠The concentration of NAD+influences the intracellular Ca2+concentration in G. lucidum. ⢠The concentration of NAD+influences cellulase production by eliciting a change in intracellular Ca2+in G. lucidum.
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Cálcio/metabolismo , Celulase/biossíntese , Nicotinamida-Nucleotídeo Adenililtransferase/metabolismo , Reishi/enzimologia , Reishi/crescimento & desenvolvimento , Espaço Intracelular/química , NAD/biossíntese , Nicotinamida-Nucleotídeo Adenililtransferase/genética , Reishi/genéticaRESUMO
Oxygen vacancies are usually considered to be beneficial in catalytic conversion of polysulfides in lithium-sulfur batteries. Now it is demonstrated that the conversion of polysulfides was hindered by oxygen vacancies on ultrathin niobic acid. The inferior performance induced by the oxygen vacancy was mainly attributed to the decreased electric conductivity as well as the weakened adsorption of polysulfides on the catalyst surface. This work shows that the care should be taken when designing a new catalyst for the lithium-sulfur battery using a defect-engineering strategy.
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A carbon thin film/carbon foam core/sheath structure was synthesized by chemical vapor deposition (CVD) on carbonized melamine foam. It has a specific capacitance of 310â F g-1 at a current density of 1â A g-1 and shows outstanding electrochemical performance in both aqueous and water-in-salt electrolytes. Electrochemical analysis by cyclic voltammetry and galvanostatic charge/discharge testing revealed a large capacitive contribution up to more than 90 % of its total capacitance. The core/sheath structure has advantages in ion transport and a high degree of utilization of the electrode surface, and the synthetic process provides a way to coat carbon thin film on any substrate by nickel-catalyzed CVD.
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Copper fluoride (CuF2 ) has the highest energy density among all metal fluoride cathodes owing to its high theoretical potential (3.55 V) and high capacity (528 mAh g-1 ). However, CuF2 can only survive for less than five cycles, mainly due to serious Cu-ion dissolution during charge/discharge cycles. Herein, copper dissolution is successfully suppressed by forming Cu2+ -coordinated sodium alginate (Cu-SA) on the surface of CuF2 particles during the electrode fabrication process, by using water as a slurry solvent and sodium alginate (SA) as a binder. The trace dissolved Cu2+ in water from CuF2 can in situ cross-link with SA binder forming a conformal Cu-SA layer on CuF2 surface. After water evaporation during the electrode dry process, the Cu-SA layer is Li-ion conductor but Cu2+ insulator, which can effectively suppress the dissolution of Cu-ions in the organic 4 m LiClO4 /ethylene carbonate/propylene carbonate electrolyte, enhancing the reversibility of CuF2 . CuF2 electrode with SA binder delivers a reversible capacity of 420.4 mAh g-1 after 50 cycles at 0.05 C, reaching an energy density of 1009.1 Wh kg-1 . Cu2+ cross-link polymer coating on CuF2 opens the door for stabilizing the high-energy and low-cost CuF2 cathode for next-generation Li-ion batteries.
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Single-crystalline cathode materials have attracted intensive interest in offering greater capacity retention than their polycrystalline counterparts by reducing material surfaces and phase boundaries. However, the single-crystalline LiCoO2 suffers severe structural instability and capacity fading when charged to high voltages (4.6 V) due to Co element dissolution and O loss, crack formation, and subsequent electrolyte penetration. Herein, by forming a robust cathode electrolyte interphase (CEI) in an all-fluorinated electrolyte, reversible planar gliding along the (003) plane in a single-crystalline LiCoO2 cathode is protected due to the prevention of element dissolution and electrolyte penetration. The robust CEI effectively controls the performance fading issue of the single-crystalline cathode at a high operating voltage of 4.6 V, providing new insights for improved electrolyte design of high-energy-density battery cathode materials.
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Putrescine (Put) has been shown to play an important regulatory role in cell growth in organisms. As the primary center regulating the homeostasis of polyamine (PA) content, ornithine decarboxylase antizyme (AZ) can regulate PA content through feedback. Nevertheless, the regulatory mechanism of Put is poorly understood in fungi. Here, our analysis showed that GlAZ had a modulate effect on intracellular Put content by interacting with ornithine decarboxylase (ODC) proteins and reducing its intracellular protein levels. In addition, GlAZ upregulated the metabolic pathway of ganoderic acid (GA) biosynthesis in Ganoderma lucidum by modulating the intracellular Put content. However, a target of rapamycin (TOR) was found to promote the accumulation of intracellular Put after the GlTOR inhibitor Rap was added exogenously, and unbiased analyses demonstrated that GlTOR may promote Put production through its inhibitory effect on the level of GlAZ protein in GlTOR-GlAZ-cosilenced strains. The effect of TOR on fungal secondary metabolism was further explored, and the content of GA in the GlTOR-silenced strain after the exogenous addition of the inhibitor Rap was significantly increased compared with that in the untreated wild-type (WT) strain. Silencing of TOR in the GlTOR-silenced strains caused an increase in GA content, which returned to the WT state after replenishing Put. Moreover, the content of GA in GlTOR-GlAZ-cosilenced strains was also not different from that in the WT strain. Consequently, these results strongly indicate that GlTOR affects G. lucidum GA biosynthesis via GlAZ. IMPORTANCE Research on antizyme (AZ) in fungi has focused on the mechanism by which AZ inhibits ornithine decarboxylase (ODC). Moreover, there are existing reports on the regulation of AZ protein translation by TOR. However, little is known about the mechanisms that influence AZ in fungal secondary metabolism. Here, both intracellular Put content and GA biosynthesis in G. lucidum were shown to be regulated through protein interactions between GlAZ and GlODC. Furthermore, exploration of upstream regulators of GlAZ suggested that GlAZ was regulated by the upstream protein GlTOR, which affected intracellular Put levels and ganoderic acid (GA) biosynthesis. The results of our work contribute to the understanding of the upstream regulation of Put and provide new insights into PA regulatory systems and secondary metabolism in fungi.
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Reishi , Reishi/metabolismo , Putrescina/metabolismo , Ornitina Descarboxilase/genética , Ornitina Descarboxilase/metabolismo , Sirolimo/metabolismo , Poliaminas/metabolismoRESUMO
2D nanomaterials generally exhibit enhanced physiochemical and biological functions in biomedical applications due to their high surface-to-volume ratio and surface charge. Conventional cancer chemotherapy based on nanomaterials has been hindered by their low drug loading and poor penetration in tumor tissue. To overcome these difficulties, novel materials systems are urgently needed. Hereby, the lanthanide-based porphyrin metal-organic framework (MOF) nanosheets (NSs) with promising cancer imaging/chemotherapy capacities are fabricated, which display superior performance in the drug loading and tumor tissue penetration. The biodegradable PPF-Gd NSs deliver an ultrahigh drug loading (>1500%) and demonstrate the stable and highly sensitive stimuli-responsive degradation/release for multimodal tumor imaging and cancer chemotherapy. Meanwhile, PPF-Gd NSs also exhibit excellent fluorescence and magnetic resonance imaging capability in vitro and in vivo. Compared to the traditional doxorubicin (DOX) chemotherapy, the in vivo results confirm the evident suppression of the tumor growth by the PPF-Gd/DOX drug delivery system with negligible side effects. This work further supports the potential of lanthanide-based MOF nanomaterials as biodegradable systems to promote the cancer theranostics technology development in the future.
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The transcription factor PacC/Rim101 participates in environmental pH adaptation, development and secondary metabolism in many fungi, but whether PacC/Rim101 contributes to fungal adaptation to environmental stress remains unclear. In our previous study, a homologous gene of PacC/Rim101 was identified, and PacC-silenced strains of the agaricomycete Ganoderma lucidum were constructed. In this study, we further investigated the functions of PacC in G. lucidum and found that PacC-silenced strains were hypersensitive to environmental stresses, such as osmotic stress, oxidative stress and cell wall stress, compared with wild-type (WT) and empty-vector control (CK) strains. In addition, transmission electron microscopy images of the cell wall structure showed that the cell walls of the PacC-silenced strains were thinner (by approximately 25-30%) than those of the WT and CK strains. Further analysis of cell wall composition showed that the ß-1,3-glucan content in the PacC-silenced strains was only approximately 78-80% of that in the WT strain, and the changes in ß-1,3-glucan content were consistent with downregulation of glucan synthase gene expression. The ability of PacC to bind to the promoters of glucan synthase-encoding genes confirms that PacC transcriptionally regulates these genes.
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Parede Celular/química , Proteínas Fúngicas/metabolismo , Reishi/metabolismo , Fatores de Transcrição/metabolismo , Adaptação Fisiológica , Parede Celular/genética , Parede Celular/metabolismo , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Estresse Oxidativo , Reishi/genética , Fatores de Transcrição/genética , beta-Glucanas/química , beta-Glucanas/metabolismoRESUMO
Two-dimensional (2D) ultrathin nanomaterials have shown extensive attention and potential biomedical applications in cancer theranostics. Herein, for the first time, we report the synthesis of monodisperse ultrathin lanthanum oxyiodide (LaOI) nanosheets with a thickness of merely 3 nm based on a facile wet chemistry strategy. By tuning the solvent composition and molar ratios of the precursors, we can modulate the shape and thickness of the nanosheets. Furthermore, a series of ultrathin lanthanide oxyiodides are synthesized by this method with tunable morphology. LaOI nanosheets as drug delivery platform showed ultrahigh anticancer doxorubicin (DOX) loading capacity (300 wt%) and pH-responsive release behaviour, as well as excellent cellular biocompatibility and efficiently intracellular nucleus delivery of DOX. LaOI with low dose DOX demonstrate enhanced cancer cell killing ability in vitro compared with DOX. The intravenous melanoma model shows that LaOI with low dose (1 mg mL-1) could significantly inhibit the tumor growth without side toxicity, relative to pure DOX. In addition, LaOI nanosheets also act as high resolution contrast agent for enhanced X-ray computed tomography imaging relative to the commercial iohexol. In summary, the LaOI nanosheets could serve as a competitive safe and low dose drug delivery platform for highly efficiently cancer imaging and therapy.
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Antineoplásicos , Elementos da Série dos Lantanídeos , Neoplasias , Antineoplásicos/uso terapêutico , Doxorrubicina/uso terapêutico , Humanos , Elementos da Série dos Lantanídeos/uso terapêutico , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Medicina de Precisão , Nanomedicina Teranóstica , Tomografia Computadorizada por Raios XRESUMO
When fungi are subjected to abiotic stresses, the polyamines (PAs) level alter significantly. Here, we reveal that the polyamine putrescine (Put) could play an important role in alleviating heat stress(HS)-induced accumulation of nitric oxide (NO). Ornithine decarboxylase (ODC)-silenced mutants that were defective in Put biosynthesis exhibited significantly lower NO levels than the wild type (WT) when subjected to HS. With addition of 5 mM exogenous Put, the ODC-silenced mutant endogenous Put obviously increased under HS. At the same time, the contents of NO in the ODC-silenced mutants recovered to approximately WT levels after the administration of exogenous Put. However, the elevated NO content in the ODC-silenced mutants disappeared when exogenous Put and carboxy-PTIO (PTIO is a specific scavenger of NO) were added. Intriguingly, the content of glutamine (Gln) was significantly increased in the ODC-silenced strains. When exogenous Put was added to the WT, the Gln content was significantly decreased. The appearance of a high level of Gln was accompanied by nitrate reductase (NR) activity reduction. Further studies showed that Put influenced ganoderic acids (GAs) biosynthesis by regulating NO content, possibly through NR, under HS. Our work reported that Put regulates HS-induced NO accumulation by changing the cellular Gln level in filamentous fungi. IMPORTANCE: In our present work, it was HS as an ubiquitous environmental stress that affects the important pharmacological secondary metabolite (GAs) content in G. lucidum. Afterwards, we began to explore the network formed between multiple substances to jointly reduce the massive accumulation of GAs content caused by HS. We firstly focused on Put, a substance that enhances resistance to multiple stresses. Further, we discovered an inï¬uence on Put could changing the NO content, which has been shown to decrease the accumulation of GAs via HS. Then, we also found the change of NO content may be due to Put level that would affect intracellular Gln content. It has never been reported. And ultimately, it is Put related network that could reduce HS-inducing secondary metabolite mess in fungi.
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Glutamina/metabolismo , Óxido Nítrico/metabolismo , Putrescina/metabolismo , Reishi/metabolismo , Regulação Fúngica da Expressão Gênica , Resposta ao Choque Térmico , Temperatura Alta , Nitrato Redutase/metabolismo , Ornitina Descarboxilase/genética , Reishi/genética , Triterpenos/metabolismoRESUMO
Na2Ti3O7 is considered as a promising anode material for sodium ion batteries (SIBs) due to its excellent high-rate performance compared with hard carbons. However, the electrochemical performance of Na2Ti3O7 is heavily limited by its low electrical conductivity. In this study, we synthesized a series of lanthanide (Ln = La, Ce, Nd, Sm, Gd, Er, and Yb) doped microsized Na2Ti3O7 anode materials and systematically studied the electrochemical performance. Compared with pristine Na2Ti3O7, all the doped samples show superior electrochemical performance. Especially, the Yb3+ doped sample not only delivers a high reversible capacity of 89.4 mA h g-1 at 30C, but also maintains 71.6 mA h g-1 at 5C after 1600 cycles, nearly twice that of pristine Na2Ti3O7. It is found for the first time that the enhancement in doped samples is attributed to the introduction of lanthanides which induces lattice distortion and oxygen vacancies.