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A great challenge in the commercialization process of layered Ni-rich cathode material LiNixCoyMn1-x-yO2 (NCM, x ≥ 80%) for lithium-ion batteries is the surface instability, which is exacerbated by the increase in nickel content. The high surface alkalinity and unavoidable cathode/electrolyte interface side reactions result in significant decrease for the capacity of NCM material. Surface coating and doping are common and effective ways to improve the electrochemical performance of Ni-rich cathode material. In this study, an in situ reaction is induced on the surface of secondary particles of NCM material to construct a stable lithium sulfate coating, while achieving sulfur doping in the near surface region. The synergistic modification of lithium sulfate coating and lattice sulfur doping significantly reduced the content of harmful residual lithium compounds (RLCs) on the surface of NCM material, suppressed the side reactions between the cathode material surface and electrolyte and the degradation of surface structure of the NCM material, effectively improved the rate capability and cycling stability of the NCM material.
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The rapid growth of flexible quasi-solid-state thermocells (TECs) provides a fresh way forward for wearable electronics. However, their insufficient mechanical strength and power output still hinder their further applications. This work demonstrates a one-stone-two-birds strategy to synergistically enhance the mechanical and thermoelectrochemical properties of the [Fe(CN)6]3-/4--based TECs. By introducing Hofmeister effect and multiple non-covalent interactions via betaine zwitterions, the mechanical strength of the conventional brittle gelatin hydrogel electrolytes is substantially improved from 50 to 440â kPa, with a high stretchability approaching 250 %. Meanwhile, the betaine zwitterions strongly affect the solvation structure of [Fe(CN)6]3- ions, thus enlarging the entropy difference and raising the thermoelectrochemical Seebeck coefficient from 1.47 to 2.2â mV K-1. The resultant quasi-solid-state TECs exhibit a normalized output power density of 0.48â mW m-2 K-2, showing a notable improvement in overall performance compared to their counterparts without zwitterion regulation. The intrinsic thermo-reversible property also allows the TECs to repeatedly self-recover through sol-gel transformations, ensuring reliable energy output and even recycling of TECs in case of extreme mechanical damages. An energy-autonomous smart glove consisting of eighteen individual TECs is further designed, which can simultaneously monitor the temperature of different positions on any touched object, demonstrating high potential in wearable applications.
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The interfacial instability of high-nickel layered oxides severely plagues practical application of high-energy quasi-solid-state lithium metal batteries (LMBs). Herein, a uniform and highly oxidation-resistant polymer layer within inner Helmholtz plane is engineered by in situ polymerizing 1-vinyl-3-ethylimidazolium (VEIM) cations preferentially adsorbed on LiNi0.83Co0.11Mn0.06O2 (NCM83) surface, inducing the formation of anion-derived cathode electrolyte interphase with fast interfacial kinetics. Meanwhile, the copolymerization of [VEIM][BF4] and vinyl ethylene carbonate (VEC) endows P(VEC-IL) copolymer with the positively-charged imidazolium moieties, providing positive electric fields to facilitate Li+ transport and desolvation process. Consequently, the Li||NCM83 cells with a cut-off voltage up to 4.5â V exhibit excellent reversible capacity of 130â mAh g-1 after 1000â cycles at 25 °C and considerable discharge capacity of 134â mAh g-1 without capacity decay after 100â cycles at -20 °C. This work provides deep understanding on tailoring electric double layer by cation specific adsorption for high-voltage quasi-solid-state LMBs.
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Transmembrane protease serine 2 (TMPRSS2) is a membrane-bound protease expressed in many human epithelial tissues, including the airway and lung. TMPRSS2-mediated cleavage of viral spike protein is a key mechanism in severe acute respiratory syndrome coronavirus 2 activation and host cell entry. To date, the cellular mechanisms that regulate TMPRSS2 activity and cell surface expression are not fully characterized. In this study, we examined two major post-translational events, zymogen activation and N-glycosylation, in human TMPRSS2. In experiments with human embryonic kidney 293, bronchial epithelial 16HBE, and lung alveolar epithelial A549 cells, we found that TMPRSS2 was activated via intracellular autocatalysis and that this process was blocked in the presence of hepatocyte growth factor activator inhibitors 1 and 2. By glycosidase digestion and site-directed mutagenesis, we showed that human TMPRSS2 was N-glycosylated. N-glycosylation at an evolutionarily conserved site in the scavenger receptor cysteine-rich domain was required for calnexin-assisted protein folding in the endoplasmic reticulum and subsequent intracellular trafficking, zymogen activation, and cell surface expression. Moreover, we showed that TMPRSS2 cleaved severe acute respiratory syndrome coronavirus 2 spike protein intracellularly in human embryonic kidney 293 cells. These results provide new insights into the cellular mechanism in regulating TMPRSS2 biosynthesis and function. Our findings should help to understand the role of TMPRSS2 in major respiratory viral diseases.
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COVID-19 , Serina Proteasas , Humanos , Serina Proteasas/metabolismo , Glicosilación , COVID-19/genética , SARS-CoV-2/metabolismo , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/metabolismo , Precursores Enzimáticos/metabolismo , Internalización del Virus , Serina Endopeptidasas/genética , Serina Endopeptidasas/metabolismoRESUMEN
Single-atom catalysts have been paid more attention to improving sluggish reaction kinetics and anchoring polysulfide for lithium-sulfur (Li-S) batteries. It has been demonstrated that d-block single-atom elements in the fourth period can chemically interact with the local environment, leading to effective adsorption and catalytic activity toward lithium polysulfides. Enlightened by theoretical screening, for the first time, we design novel single-atom Nb catalysts toward improved sulfur immobilization and catalyzation. Calculations reveal that Nb-N4 active moiety possesses abundant unfilled antibonding orbitals, which promotes d-p hybridization and enhances anchoring capability toward lithium polysulfides via a "trapping-coupling-conversion" mechanism. The Nb-SAs@NC cell exhibits a high capacity retention of over 85% after 1000 cycles, a superior rate performance of 740 mA h g-1 at 7 C, and a competitive areal capacity of 5.2 mAh cm-2 (5.6 mg cm-2). Our work provides a new perspective to extend cathodes enabling high-energy-density Li-S batteries.
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Fe single atoms and N co-doped carbon nanomaterials (Fe-N-C) are the most promising oxygen reduction reaction (ORR) catalysts to replace platinum group metals. However, high-activity Fe single-atom catalysts suffer from poor stability owing to the low graphitization degree. Here, an effective phase-transition strategy is reported to enhance the stability of Fe-N-C catalysts by inducing increased degree of graphitization and incorporation of Fe nanoparticles encapsulated by graphitic carbon layer without sacrificing activity. Remarkably, the resulted Fe@Fe-N-C catalysts achieved excellent ORR activity (E1/2 = 0.829 V) and stability (19 mV loss after 30K cycles) in acid media. Density functional theory (DFT) calculations agree with experimental phenomena that additional Fe nanoparticles not only favor to the activation of O2 by tailoring d-band center position but also inhibit the demetallization of Fe active center from FeN4 sites. This work provides a new insight into the rational design of highly efficient and durable Fe-N-C catalysts for ORR.
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The local coordination environment of catalytical moieties directly determines the performance of electrochemical energy storage and conversion devices, such as Li-O2 batteries (LOBs) cathode. However, understanding how the coordinative structure affects the performance, especially for non-metal system, is still insufficient. Herein, a strategy that introduces S-anion to tailor the electronic structure of nitrogen-carbon catalyst (SNC) is proposed to improve the LOBs performance. This study unveils that the introduced S-anion effectively manipulates the p-band center of pyridinic-N moiety, substantially reducing the battery overpotential by accelerating the generation and decomposition of intermediate products Li1-3 O4 . The lower adsorption energy of discharging product Li2 O2 on NS pair accounts for the long-term cyclic stability by exposing the high active area under operation condition. This work demonstrates an encouraging strategy to enhance LOBs performance by modulating the p-band center on non-metal active sites.
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The potential application of zinc air batteries to tackle the energy shortage and environmental crisis has proposed new requirements of bifunctional catalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Utilizing the special spatial structure of zeolitic imidazolate framework-67 (ZIF-67) as an ideal research platform, the effect of a trace amount of Fe on the composition and structure of as-obtained Fe-CoNC catalysts was investigated. It was revealed that, due to the increased exposed pore structure and metal species located at the near surface, the active sites for the ORR/OER on Fe-CoNC are highly exposed, greatly boosting the activity to the reduction and evolution of oxygen in alkaline media. ZABs with Fe-CoNC have the highest maximum power density of 200 mW cm-2 when operated at current densities as high as 328 mA cm-2, better than not only Fe-free CoNC, but also precious metal-based references with the same catalyst loading.
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With the development of flexible devices, it is necessary to design high-performance power supplies with superior flexibility, durability, safety, etc., to ensure that they can be deformed with the device while retaining their electrochemical functions. Herein, we have designed a flexible lithium-ion battery inspired by the DNA helix structure. The battery structure is mainly composed of multiple thick energy stacks for energy storage and some grooves for stress buffers, which realized the spiral deformation of batteries. According to the results, the batteries exhibit less than 3% capacity degradation even after more than 31000 times of in situ dynamic mechanical loadings. Moreover, the mechanism of the battery with spiral deformability is further revealed. It is anticipated that this bioinspired design strategy could create unique opportunities for the commercialization of flexible batteries and fill the current gap in realizing battery-specific deformations to meet various requirements for future complex device designs.
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Suministros de Energía Eléctrica , Litio , ADN , Iones , Litio/químicaRESUMEN
Clubroot disease is a soil-borne disease caused by Plasmodiophora brassicae. It occurs in cruciferous crops exclusively, and causes serious damage to the economic value of cruciferous crops worldwide. Although different measures have been taken to prevent the spread of clubroot disease, the most fundamental and effective way is to explore and use disease-resistance genes to breed resistant varieties. However, the resistance level of plant hosts is influenced both by environment and pathogen race. In this work, we described clubroot disease in terms of discovery and current distribution, life cycle, and race identification systems; in particular, we summarized recent progress on clubroot control methods and breeding practices for resistant cultivars. With the knowledge of these identified resistance loci and R genes, we discussed feasible strategies for disease-resistance breeding in the future.
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Brassicaceae , Plasmodiophorida , Brassicaceae/genética , Fitomejoramiento , Resistencia a la Enfermedad/genética , Genes de Plantas , China , Plasmodiophorida/genética , Enfermedades de las Plantas/genéticaRESUMEN
BACKGROUND: Adverse childhood experiences (ACEs) affect children's development, and their harm to health is pervasive throughout the life course. AIMS: To identify ACEs and their risk factors in Chinese household with or without parental mental illness. METHODS: A controlled study was conducted among 181 young adults with parental mental illness (positive group) and 201 demographically matched individuals without parental mental illness (negative group). Univariate and multivariate analyses were performed to study the correlation between ACEs and their risk factors. RESULTS: The positive group suffered emotional abuse, domestic violence, bullying, and cumulative ACEs more frequently than the negative group. In the positive group, living in rural areas and having a low household economic status during childhood were identified as risk factors for cumulative ACEs, whereas a higher education level of the mother was a protective factor for cumulative ACEs in univariate analyses. Low household economic status remained an independent risk factor for cumulative ACEs in the positive group in multivariate analyses. CONCLUSIONS: Children living with parental mental illness are more vulnerable to ACEs, and our findings highlight the importance of socioeconomic factors in increasing the risk of ACEs. To alleviate the deleterious impact of parental mental illness on offspring, multidimensional supports are needed.
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Experiencias Adversas de la Infancia , Trastornos Mentales , Niño , Adulto Joven , Humanos , Padres , Proyectos de Investigación , China/epidemiología , Trastornos Mentales/epidemiologíaRESUMEN
Emerging directions in the growing wearable electronics market have spurred the development of flexible energy storage systems that require deformability while maintaining electrochemical performance. However, the traditional fabrication approaches of lithium-ion batteries (LIBs) are challenging to withstand long-cycle bending alternating loads due to the stress concentration caused by the nonuniformity of the actual deformation. Herein, inspired by kirigami, a segmented deformation design of full-cell scale thin-type flexible lithium-ion batteries (FLIBs) with large-scale manufacturing characteristics via the current collector's mechanical blanking process is reported. This strategy allows the battery's elliptical deformation of the actual state to be transformed into the circular strain of the ideal configuration, thereby dispersing the stress concentration on the top of the battery. According to the results, the designed battery maintains >95% capacity after >20 000 harsh in situ dynamic tests. In addition, finite element analysis further reveals the mechanism that the segmented deformation strategy bears the mechanical stress. This work can enlighten the rational design and customization of electrode patterns for high compatibility with various devices, thereby providing potential opportunities for the application of FLIBs.
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Mitigating the mechanical degradation and enhancing the ionic/electronic conductivity are critical but challengeable issues toward improving electrochemical performance of conversion-type anodes in rechargeable batteries. Herein, these challenges are addressed by constructing interconnected 3D hierarchically porous structure synergistic with Nb single atom modulation within a Co3 O4 nanocage (3DH-Co3 O4 @Nb). Such a hierarchical-structure nanocage affords several fantastic merits such as rapid ion migration and enough inner space for alleviating volume variation induced by intragrain stress and optimized stability of the solid-electrolyte interface. Particularly, experimental studies in combination with theoretical analysis verify that the introduction of Nb into the Co3 O4 lattice not only improves the electron conductivity, but also accelerates the surface/near-surface reactions defined as pesudocapacitance behavior. Dynamic behavior reveals that the ensemble design shows huge potential for fast and large lithium storage. These features endow 3DH-Co3 O4 @Nb with remarkable battery performance, delivering ≈740 mA h g-1 after ultra-long cycling of 1000 times under a high current density of 5 A g-1 . Importantly, the assembled 3DH-Co3 O4 @Nb//LiCoO2 pouch cell also presents a long-lived cycle performance with only ≈0.059% capacity decay per cycle, inspiring the design of electrode materials from both the nanostructure and atomic level toward practical applications.
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Atrial natriuretic peptide (ANP)-mediated natriuresis is known as a cardiac endocrine function in sodium and body fluid homeostasis. Corin is a protease essential for ANP activation. Here, we studied the role of renal corin in regulating salt excretion and blood pressure. We created corin conditional knockout (cKO), in which the Corin gene was selectively disrupted in the kidney (kcKO) or heart (hcKO). We examined the blood pressure, urinary Na+ and Cl- excretion, and cardiac hypertrophy in wild-type, corin global KO, kcKO, and hcKO mice fed normal- and high-salt diets. We found that on a normal-salt diet (0.3% NaCl), corin kcKO and hcKO mice had increased blood pressure, indicating that both renal and cardiac corin is necessary for normal blood pressure in mice. On a high-salt diet (4% NaCl), reduced urinary Na+ and Cl- excretion, increased body weight, salt-exacerbated hypertension, and cardiac hypertrophy were observed in corin kcKO mice. In contrast, impaired urinary Na+ and Cl- excretion and salt-exacerbated hypertension were not observed in corin hcKO mice. These results indicated that renal corin function is important in enhancing natriuresis upon high salt intakes and that this function cannot be compensated by the cardiac corin function in mice.
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Factor Natriurético Atrial , Hipertensión , Animales , Factor Natriurético Atrial/genética , Presión Sanguínea/fisiología , Cardiomegalia , Homeostasis , Hipertensión/genética , Riñón , Ratones , Serina Endopeptidasas/genética , Sodio , Cloruro de Sodio , Cloruro de Sodio Dietético/efectos adversosRESUMEN
BACKGROUND: Mental disorders impose heavy burdens on patients' families and children. It is imperative to provide family-focused services to avoid adverse effects from mental disorders on patients' families and children. However, implementing such services requires a great deal of involvement of mental health workers. This study investigated the attitudes, knowledge, skills, and practices in respect to family-focused practices (FFP) in a sample of Chinese mental health workers. METHODS: A cross-sectional study design was employed to examine the attitudes, knowledge, skills, and practices of a convenience sample of Chinese mental health workers in respect to FFP, using the Chinese version of the Family-Focused Mental Health Practice Questionnaire (FFMHPQ). RESULTS: In total, 515 mental health workers participated in our study, including 213 psychiatrists, 269 psychiatric nurses, and 34 allied mental health professionals (20 clinical psychologists, 9 mental health social workers, and 4 occupational therapists). Compared with psychiatric nurses, psychiatrists and allied mental health professionals provided more support for families and children of patients with mental illness and were more willing to receive further training in FFP. However, there were no significant differences on knowledge, skills, and confidence across different profession types. After adjusting for demographic and occupational variables, previous training in FFP was positively associated with mental health workers' knowledge, skills, and confidence about FFP, but not actual support to families and children. CONCLUSIONS: Professional differences on FFP exist in Chinese mental health workers. Training is needed to engage psychiatrists and other allied workforce in dissemination and implementation of FFP in China.
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Trastornos Mentales , Enfermería Psiquiátrica , Niño , China , Estudios Transversales , Personal de Salud , Humanos , Trastornos Mentales/terapia , Salud MentalRESUMEN
Although the combination of Airborne Laser Scanning (ALS) data and optical imagery and machine learning algorithms were proved to improve the estimation of aboveground biomass (AGB), the synergistic approaches of different data and ensemble learning algorithms have not been fully investigated, especially for natural secondary forests (NSFs) with complex structures. This study aimed to explore the effects of the two factors on AGB estimation of NSFs based on ALS data and Landsat 8 imagery. The synergistic method of extracting novel features (i.e., COLI1 and COLI2) using optimal Landsat 8 features and the best-performing ALS feature (i.e., elevation mean) yielded higher accuracy of AGB estimation than either optical-only or ALS-only features. However, both of them failed to improve the accuracy compared to the simple combination of the untransformed features that generated them. The convolutional neural networks (CNN) model was much superior to other classic machine learning algorithms no matter of features. The stacked generalization (SG) algorithms, a kind of ensemble learning algorithms, greatly improved the accuracies compared to the corresponding base model, and the SG with the CNN meta-model performed best. This study provides technical support for a wall-to-wall AGB mapping of NSFs of northeastern China using efficient features and algorithms.
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Bosques , Aprendizaje Automático , Biomasa , China , Rayos LáserRESUMEN
The essence of developing a Pt-based single-atom catalyst (SAC) for hydrogen evolution reaction (HER) is the preparation of well-defined and stable single Pt sites with desired electrocatalytic efficacy. Herein, we report a facile approach to generate uniformly dispersed Pt sites with outstanding HER performance via a photochemical reduction method using polyvinylpyrrolidone (PVP) molecules as the key additive to significantly simplify the synthesis and enhance the catalytic performance. The as-prepared catalyst displays remarkable kinetic activities (20 times higher current density than the commercially available Pt/C) with excellent stability (76.3 % of its initial activity after 5000â cycles) for HER. EXAFS measurements and DFT calculations demonstrate a synergetic effect, where the PVP ligands and the support together modulate the electronic structure of the Pt atoms, which optimize the hydrogen adsorption energy, resulting in a considerably improved HER activity.
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Titanium-based oxides including TiO2 and M-Ti-O compounds (M = Li, Nb, Na, etc.) family, exhibit advantageous structural dynamics (2D ion diffusion path, open and stable structure for ion accommodations) for practical applications in energy storage systems, such as lithium-ion batteries, sodium-ion batteries, and hybrid pseudocapacitors. Further, Ti-based oxides show high operating voltage relative to the deposition of alkali metal, ensuring full safety by avoiding the formation of lithium and sodium dendrites. On the other hand, high working potential prevents the decomposition of electrolyte, delivering excellent rate capability through the unique pseudocapacitive kinetics. Nevertheless, the intrinsic poor electrical conductivity and reaction dynamics limit further applications in energy storage devices. Recently, various work and in-depth understanding on the morphologies control, surface engineering, bulk-phase doping of Ti-based oxides, have been promoted to overcome these issues. Inspired by that, in this review, the authors summarize the fundamental issues, challenges and advances of Ti-based oxides in the applications of advanced electrochemical energy storage. Particularly, the authors focus on the progresses on the working mechanism and device applications from lithium-ion batteries to sodium-ion batteries, and then the hybrid pseudocapacitors. In addition, future perspectives for fundamental research and practical applications are discussed.
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The oxygen reduction reaction (ORR) plays an important role in the fields of energy storage and conversion technologies, including metal-air batteries and fuel cells. The development of nonprecious metal electrocatalysts with both high ORR activity and durability to replace the currently used costly Pt-based catalyst is critical and still a major challenge. Herein, a facile and scalable method is reported to prepare ZIF-8 with single ferrocene molecules trapped within its cavities (Fc@ZIF-8), which is utilized as precursor to porous single-atom Fe embedded nitrogen-doped carbon (Fe-N-C) during high temperature pyrolysis. The catalyst shows a half-wave potential (E1/2 ) of 0.904 V, 67 mV higher than commercial Pt/C catalyst (0.837 V), which is among the best compared with reported results for ORR. Significant electrochemical properties are attributed to the special configuration of Fc@ZIF-8 transforming into a highly dispersed iron-nitrogen coordination moieties embedded carbon matrix.
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Fire warning is vital to human life, economy and ecology. However, the development of effective warning systems faces great challenges of fast response, adjustable threshold and remote detecting. Here, we propose an intelligent self-powered remote IoT fire warning system, by employing single-walled carbon nanotube/titanium carbide thermoelectric composite films. The flexible films, prepared by a convenient solution mixing, display p-type characteristic with excellent high-temperature stability, flame retardancy and TE (power factor of 239.7 ± 15.8 µW m-1 K-2) performances. The comprehensive morphology and structural analyses shed light on the underlying mechanisms. And the assembled TE devices (TEDs) exhibit fast fire warning with adjustable warning threshold voltages (1-10 mV). Excitingly, an ultrafast fire warning response time of ~ 0.1 s at 1 mV threshold voltage is achieved, rivaling many state-of-the-art systems. Furthermore, TE fire warning systems reveal outstanding stability after 50 repeated cycles and desired durability even undergoing 180 days of air exposure. Finally, a TED-based wireless intelligent fire warning system has been developed by coupling an amplifier, analog-to-digital converter and Bluetooth module. By combining TE characteristics, high-temperature stability and flame retardancy with wireless IoT signal transmission, TE-based hybrid system developed here is promising for next-generation self-powered remote IoT fire warning applications.