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1.
Nano Lett ; 24(25): 7783-7791, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38869099

RESUMEN

The increasing use of low-cost lithium iron phosphate cathodes in low-end electric vehicles has sparked interest in Prussian blue analogues (PBAs) for lithium-ion batteries. A major challenge with iron hexacyanoferrate (FeHCFe), particularly in lithium-ion systems, is its slow kinetics in organic electrolytes and valence state inactivation in aqueous ones. We have addressed these issues by developing a polymeric cathode electrolyte interphase (CEI) layer through a ring-opening reaction of ethylene carbonate triggered by OH- radicals from structural water. This facile approach considerably mitigates the sluggish electrochemical kinetics typically observed in organic electrolytes. As a result, FeHCFe has achieved a specific capacity of 125 mAh g-1 with a stable lifetime over 500 cycles, thanks to the effective activation of Fe low-spin states and the structural integrity of the CEI layers. These advancements shed light on the potential of PBAs to be viable, durable, and efficient cathode materials for commercial use.

2.
J Virol ; 97(7): e0016123, 2023 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-37367301

RESUMEN

Parvoviruses are among the smallest and superficially simplest animal viruses, infecting a broad range of hosts, including humans, and causing some deadly infections. In 1990, the first atomic structure of the canine parvovirus (CPV) capsid revealed a 26-nm-diameter T=1 particle made up of two or three versions of a single protein, and packaging about 5,100 nucleotides of single-stranded DNA. Our structural and functional understanding of parvovirus capsids and their ligands has increased as imaging and molecular techniques have advanced, and capsid structures for most groups within the Parvoviridae family have now been determined. Despite those advances, significant questions remain unanswered about the functioning of those viral capsids and their roles in release, transmission, or cellular infection. In addition, the interactions of capsids with host receptors, antibodies, or other biological components are also still incompletely understood. The parvovirus capsid's apparent simplicity likely conceals important functions carried out by small, transient, or asymmetric structures. Here, we highlight some remaining open questions that may need to be answered to provide a more thorough understanding of how these viruses carry out their various functions. The many different members of the family Parvoviridae share a capsid architecture, and while many functions are likely similar, others may differ in detail. Many of those parvoviruses have not been experimentally examined in detail (or at all in some cases), so we, therefore, focus this minireview on the widely studied protoparvoviruses, as well as the most thoroughly investigated examples of adeno-associated viruses.


Asunto(s)
Parvoviridae , Animales , Humanos , Cápside/ultraestructura , Proteínas de la Cápside/química , Proteínas de la Cápside/metabolismo , ADN Viral/metabolismo , Parvoviridae/genética , Parvoviridae/ultraestructura , Infecciones por Parvoviridae/metabolismo , Infecciones por Parvoviridae/virología , Dependovirus/genética , Dependovirus/metabolismo , Dependovirus/ultraestructura
3.
J Virol ; 97(6): e0009023, 2023 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-37199627

RESUMEN

Canine parvovirus (CPV) is a small nonenveloped single-stranded DNA virus that causes serious diseases in dogs worldwide. The original strain of the virus (CPV-2) emerged in dogs during the late 1970s due to a host range switch of a virus similar to the feline panleukopenia virus that infected another host. The virus that emerged in dogs had altered capsid receptor and antibody binding sites, with some changes affecting both functions. Further receptor and antibody binding changes arose when the virus became better adapted to dogs or to other hosts. Here, we used in vitro selection and deep sequencing to reveal how two antibodies with known interactions select for escape mutations in CPV. The antibodies bound two distinct epitopes, and one largely overlapped the host receptor binding site. We also generated mutated antibody variants with altered binding structures. Viruses were passaged with wild-type (WT) or mutated antibodies, and their genomes were deep sequenced during the selective process. A small number of mutations were detected only within the capsid protein gene during the first few passages of selection, and most sites remained polymorphic or were slow to go to fixation. Mutations arose both within and outside the antibody binding footprints on the capsids, and all avoided the transferrin receptor type 1 binding footprint. Many selected mutations matched those that have arisen in the natural evolution of the virus. The patterns observed reveal the mechanisms by which these variants have been selected in nature and provide a better understanding of the interactions between antibody and receptor selections. IMPORTANCE Antibodies protect animals against infection by many different viruses and other pathogens, and we are gaining new information about the epitopes that induce antibody responses against viruses and the structures of the bound antibodies. However, less is known about the processes of antibody selection and antigenic escape and the constraints that apply in this system. Here, we used an in vitro model system and deep genome sequencing to reveal the mutations that arose in the virus genome during selection by each of two monoclonal antibodies or their mutated variants. High-resolution structures of each of the Fab:capsid complexes revealed their binding interactions. The wild-type antibodies or their mutated variants allowed us to examine how changes in antibody structure influence the mutational selection patterns seen in the virus. The results shed light on the processes of antibody binding, neutralization escape, and receptor binding, and they likely have parallels for many other viruses.


Asunto(s)
Anticuerpos Antivirales , Sitios de Unión de Anticuerpos , Cápside , Parvovirus Canino , Animales , Perros , Cápside/metabolismo , Proteínas de la Cápside/genética , Proteínas de la Cápside/metabolismo , Epítopos/genética , Epítopos/análisis , Parvovirus Canino/genética , Parvovirus Canino/metabolismo , Mutación , Anticuerpos Antivirales/genética , Anticuerpos Antivirales/metabolismo , Sitios de Unión de Anticuerpos/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Antígenos Virales/metabolismo , Selección Genética
4.
Scand J Med Sci Sports ; 34(6): e14675, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38864455

RESUMEN

BACKGROUND: Although individuals with anterior cruciate ligament reconstruction (ACLR) are at high risk for posttraumatic osteoarthritis, mechanisms underlying the relationship between running and knee cartilage health remain unclear. OBJECTIVE: We aimed to investigate how 30 min of running influences femoral cartilage thickness and composition and their relationships with running biomechanics in patients with ACLR and controls. METHODS: Twenty patients with ACLR (time post-ACLR: 14.6 ± 6.1 months) and 20 matched controls participated in the study. A running session required both groups to run for 30 min at a self-selected speed. Before and after running, we measured femoral cartilage thickness via ultrasound imaging. A MRI session consisted of T2 mapping. RESULTS: The ACLR group showed longer T2 relaxation times in the medial femoral condyle at resting compared with the control group (central: 51.2 ± 16.6 vs. 34.9 ± 13.2 ms, p = 0.006; posterior: 50.2 ± 10.1 vs. 39.8 ± 7.4 ms, p = 0.006). Following the run, the ACLR group showed greater deformation in the medial femoral cartilage than the control group (0.03 ± 0.01 vs. 0.01 ± 0.01 cm, p = 0.001). Additionally, the ACLR group showed significant negative correlations between resting T2 relaxation time in the medial femoral condyle and vertical impulse (standardized regression coefficients = -0.99 and p = 0.004) during running. CONCLUSIONS: Our findings suggest that those who are between 6 and 24 months post-ACLR have degraded cartilage composition and their cartilage deforms more due to running vGRF.


Asunto(s)
Reconstrucción del Ligamento Cruzado Anterior , Cartílago Articular , Fémur , Imagen por Resonancia Magnética , Carrera , Humanos , Cartílago Articular/diagnóstico por imagen , Masculino , Fenómenos Biomecánicos , Femenino , Fémur/diagnóstico por imagen , Adulto , Carrera/fisiología , Adulto Joven , Estudios de Casos y Controles , Ultrasonografía , Lesiones del Ligamento Cruzado Anterior/cirugía , Lesiones del Ligamento Cruzado Anterior/fisiopatología , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/fisiología
5.
Int J Sports Med ; 45(1): 48-54, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37972934

RESUMEN

Patients with chronic ankle instability (CAI) consistently display postural control alterations, which may result from sensorimotor dysfunction. This study aimed to compare muscle activity in the lower extremity and postural control among individuals with CAI, copers and uninjured controls during a static balance test. A total of 57 physically active participants were categorized into three groups (CAI, copers and controls) and performed a single-leg balance test with two visual conditions: eyes open and eyes closed. Muscle activity in six lower extremity muscles and center of pressure (CoP) variables were recorded and analyzed. Patients with CAI exhibited greater muscle activity in the medial gastrocnemius and gluteus maximus compared to controls or copers, regardless of the visual condition. Copers displayed increased gluteus medius activity compared to controls. Additionally, all groups demonstrated increased muscle activity and CoP variables when visual feedback was disrupted. These findings suggest that patients with CAI may have less effective recruitment of motor units during static balance. On the other hand, greater muscle activity in the gluteus medius in copers may represent a coping mechanism to avoid further ankle injuries. Further research on muscle activity during dynamic postural control is warranted to explore sensorimotor alterations in patients with CAI.


Asunto(s)
Traumatismos del Tobillo , Inestabilidad de la Articulación , Humanos , Tobillo , Articulación del Tobillo/fisiología , Músculo Esquelético/fisiología , Extremidad Inferior , Equilibrio Postural/fisiología , Enfermedad Crónica
6.
Nano Lett ; 23(8): 3582-3591, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37027522

RESUMEN

Over the past decade, lithium metal has been considered the most attractive anode material for high-energy-density batteries. However, its practical application has been hindered by its high reactivity with organic electrolytes and uncontrolled dendritic growth, resulting in poor Coulombic efficiency and cycle life. In this paper, we propose a design strategy for interface engineering using a conversion-type reaction of metal fluorides to evolve a LiF passivation layer and Li-M alloy. Particularly, we propose a LiF-modified Li-Mg-C electrode, which demonstrates stable long-term cycling for over 2000 h in common organic electrolytes with fluoroethylene carbonate (FEC) additives and over 700 h even without additives, suppressing unwanted side reactions and Li dendritic growth. With the help of phase diagrams, we found that solid-solution-based alloying not only facilitates the spontaneous evolution of a LiF layer and bulk alloy but also enables reversible Li plating/stripping inward to the bulk, compared with intermetallic compounds with finite Li solubility.

7.
Am J Physiol Renal Physiol ; 324(1): F12-F29, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36264886

RESUMEN

The renal response to acid-base disturbances involves phenotypic and remodeling changes in the collecting duct. This study examines whether the proximal tubule controls these responses. We examined mice with genetic deletion of proteins present only in the proximal tubule, either the A variant or both A and B variants of isoform 1 of the electrogenic Na+-bicarbonate cotransporter (NBCe1). Both knockout (KO) mice have spontaneous metabolic acidosis. We then determined the collecting duct phenotypic responses to this acidosis and the remodeling responses to exogenous acid loading. Despite the spontaneous acidosis in NBCe1-A KO mice, type A intercalated cells in the inner stripe of the outer medullary collecting duct (OMCDis) exhibited decreased height and reduced expression of H+-ATPase, anion exchanger 1, Rhesus B glycoprotein, and Rhesus C glycoprotein. Combined kidney-specific NBCe1-A/B deletion induced similar changes. Ultrastructural imaging showed decreased apical plasma membrane and increased vesicular H+-ATPase in OMCDis type A intercalated cell in NBCe1-A KO mice. Next, we examined the collecting duct remodeling response to acidosis. In wild-type mice, acid loading increased the proportion of type A intercalated cells in the connecting tubule (CNT) and OMCDis, and it decreased the proportion of non-A, non-B intercalated cells in the connecting tubule, and type B intercalated cells in the cortical collecting duct (CCD). These changes were absent in NBCe1-A KO mice. We conclude that the collecting duct phenotypic and remodeling responses depend on proximal tubule-dependent signaling mechanisms blocked by constitutive deletion of proximal tubule NBCe1 proteins.NEW & NOTEWORTHY This study shows that the proximal tubule regulates collecting duct phenotypic and remodeling responses to acidosis.


Asunto(s)
Acidosis , Túbulos Renales Colectores , Simportadores de Sodio-Bicarbonato , Animales , Ratones , Acidosis/genética , Acidosis/metabolismo , Glicoproteínas/metabolismo , Túbulos Renales Colectores/metabolismo , Túbulos Renales Proximales/metabolismo , Ratones Noqueados , ATPasas de Translocación de Protón/metabolismo , Simportadores de Sodio-Bicarbonato/metabolismo
8.
Small ; 19(11): e2206918, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36567426

RESUMEN

Abundant availability of seawater grants economic and resource-rich benefits to water electrolysis technology requiring high-purity water if undesired reactions such as chlorine evolution reaction (CER) competitive to oxygen evolution reaction (OER) are suppressed. Inspired by a conceptual computational work suggesting that OER is kinetically improved via a double activation within 7 Å-gap nanochannels, RuO2 catalysts are realized to have nanoscopic channels at 7, 11, and 14 Å gap in average (dgap ), and preferential activity improvement of OER over CER in seawater by using nanochanneled RuO2 is demonstrated. When the channels are developed to have 7 Å gap, the OER current is maximized with the overpotential required for triggering OER minimized. The gap value guaranteeing the highest OER activity is identical to the value expected from the computational work. The improved OER activity significantly increases the selectivity of OER over CER in seawater since the double activation by the 7 Å-nanoconfined environments to allow an OER intermediate (*OOH) to be doubly anchored to Ru and O active sites does not work on the CER intermediate (*Cl). Successful operation of direct seawater electrolysis with improved hydrogen production is demonstrated by employing the 7 Å-nanochanneled RuO2 as the OER electrocatalyst.

9.
J Virol ; 96(21): e0099022, 2022 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-36255280

RESUMEN

Ubiquitous and abundant in ecosystems and microbiomes, gokushoviruses constitute a Microviridae subfamily, distantly related to bacteriophages ΦX174, α3, and G4. A high-resolution cryo-EM structure of gokushovirus ΦEC6098 was determined, and the atomic model was built de novo. Although gokushoviruses lack external scaffolding and spike proteins, which extensively interact with the ΦX174 capsid protein, the core of the ΦEC6098 coat protein (VP1) displayed a similar structure. There are, however, key differences. At each ΦEC6098 icosahedral 3-fold axis, a long insertion loop formed mushroom-like protrusions, which have been noted in lower-resolution gokushovirus structures. Hydrophobic interfaces at the bottom of these protrusions may confer stability to the capsid shell. In ΦX174, the N-terminus of the capsid protein resides directly atop the 3-fold axes of symmetry; however, the ΦEC6098 N-terminus stretched across the inner surface of the capsid shell, reaching nearly to the 5-fold axis of the neighboring pentamer. Thus, this extended N-terminus interconnected pentamers on the inside of the capsid shell, presumably promoting capsid assembly, a function performed by the ΦX174 external scaffolding protein. There were also key differences between the ΦX174-like DNA-binding J proteins and its ΦEC6098 homologue VP8. As seen with the J proteins, C-terminal VP8 residues were bound into a pocket within the major capsid protein; however, its N-terminal residues were disordered, likely due to flexibility. We show that the combined location and interaction of VP8's C-terminus and a portion of VP1's N-terminus are reminiscent of those seen with the ΦX174 and α3 J proteins. IMPORTANCE There is a dramatic structural and morphogenetic divide within the Microviridae. The well-studied ΦX174-like viruses have prominent spikes at their icosahedral vertices, which are absent in gokushoviruses. Instead, gokushovirus major coat proteins form extensive mushroom-like protrusions at the 3-fold axes of symmetry. In addition, gokushoviruses lack an external scaffolding protein, the more critical of the two ΦX174 assembly proteins, but retain an internal scaffolding protein. The ΦEC6098 virion suggests that key external scaffolding functions are likely performed by coat protein domains unique to gokushoviruses. Thus, within one family, different assembly paths have been taken, demonstrating how a two-scaffolding protein system can evolve into a one-scaffolding protein system, or vice versa.


Asunto(s)
Cápside , Microviridae , Cápside/química , Microvirus , Proteínas de la Cápside/metabolismo , Microscopía por Crioelectrón , Ecosistema , Microviridae/química , Microviridae/metabolismo , Bacteriófago phi X 174 , Ensamble de Virus
10.
Toxicol Appl Pharmacol ; 481: 116753, 2023 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-37951547

RESUMEN

Exposure to nickel, an environmental respiratory toxicant, is associated with lung diseases including asthma, pulmonary fibrosis, bronchitis and cancers. Our previous studies have shown that a majority of the nickel-induced transcriptional changes are persistent and do not reverse even after the termination of exposure. This suggested transcriptional memory, wherein the cell 'remembers' past nickel exposure. Transcriptional memory, due to which the cells respond more robustly to a previously encountered stimulus has been identified in a number of organisms. Therefore, transcriptional memory has been described as an adaptive mechanism. However, transcriptional memory caused by environmental toxicant exposures has not been well investigated. Moreover, how the transcriptional memory caused by an environmental toxicant might influence the outcome of exposure to a second toxicant has not been explored. In this study, we investigated whether nickel-induced transcriptional memory influences the outcome of the cell's response to a second respiratory toxicant, nicotine. Nicotine, an addictive compound in tobacco, is associated with the development of chronic lung diseases including chronic obstructive pulmonary disease (COPD) and pulmonary fibrosis. Our results show that nicotine exposure upregulated a subset of genes only in the cells previously exposed to nickel. Furthermore, our analyses indicate robust activation of interferon (IFN) signaling in these cells. IFN signaling is a driver of inflammation, which is associated with many chronic lung diseases. Therefore, our results suggest that nicotine exposure of lung cells that retain the transcriptional memory of previous nickel exposure could result in increased susceptibility to developing chronic inflammatory lung diseases.


Asunto(s)
Níquel , Fibrosis Pulmonar , Humanos , Níquel/toxicidad , Nicotina/toxicidad , Fibrosis Pulmonar/patología , Pulmón/patología , Células Epiteliales , Interferones
11.
Toxicol Appl Pharmacol ; 459: 116341, 2023 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-36502870

RESUMEN

Asthma is a chronic inflammatory airway disease characterized by acute exacerbations triggered by inhaled allergens, respiratory infections, or air pollution. Ozone (O3), a major component of air pollution, can damage the lung epithelium in healthy individuals. Despite this association, little is known about the effects of O3 and its impact on chronic lung disease. Epidemiological data have demonstrated that elevations in ambient O3 are associated with increased asthma exacerbations. To identify mechanisms by which O3 exposure leads to asthma exacerbations, we developed a two-hit mouse model where mice were sensitized and challenged with three common allergens (dust mite, ragweed and Aspergillus fumigates, DRA) to induce allergic inflammation prior to exposure to O3 (DRAO3). Changes in lung physiology, inflammatory cells, and inflammation were measured. Exposure to O3 following DRA significantly increased airway hyperreactivity (AHR), which was independent of TLR4. DRA exposure resulted in increased BAL eosinophilia while O3 exposure resulted in neutrophilia. Additionally, O3 exposure following DRA blunted anti-inflammatory and antioxidant responses. Finally, there were significantly less monocytes and innate lymphoid type 2 cells (ILC2s) in the dual challenged DRA-O3 group suggesting that the lack of these immune cells may influence O3-induced AHR in the setting of allergic inflammation. In summary, we developed a mouse model that mirrors some aspects of the clinical course of asthma exacerbations due to air pollution and identified that O3 exposure in the asthmatic lung leads to impaired endogenous anti-inflammatory and antioxidant responses and alterations inflammatory cell populations.


Asunto(s)
Asma , Eosinofilia , Ozono , Ratones , Animales , Ozono/toxicidad , Inmunidad Innata , Antioxidantes/farmacología , Linfocitos , Asma/inducido químicamente , Pulmón , Inflamación , Alérgenos/toxicidad , Modelos Animales de Enfermedad
12.
Scand J Med Sci Sports ; 33(7): 1116-1124, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36840418

RESUMEN

BACKGROUND: Although chronic ankle instability (CAI) patients display altered reactive joint kinematics after inversion perturbation, little is known about the effects of anticipation on reactive joint kinematics among CAI, coper, and control groups. OBJECTIVE: To assess changes in reactive joint kinematics after different inverted landing situations including planned- and unplanned-condition among groups of CAI, coper, and control. METHODS: Sixty-six volunteers participated (22 per group). Participants completed three trials of both planned and unplanned single-leg landing onto an inverted force platform while reactive joint kinematic data were collected from initial-contact to 200 ms after initial-contact. Two-way repeated measures ANOVAs were used to examine the differences between condition (planned-, unplanned-conditions) and group (CAI, coper, control). RESULTS: There were significant group by condition interactions for total ankle displacement in the frontal plane (p < 0.01) and maximum ankle inversion velocity (p = 0.01). CAI patients displayed increased ankle displacement (p < 0.01) and maximum inversion velocity (p < 0.01) under the unplanned condition compared to the planned condition. However, copers did not show any differences in ankle displacement and maximum inversion velocity between the two conditions. CONCLUSIONS: CAI patients displayed greater changes in ankle joint displacement and maximum ankle inversion velocity occurred after inversion perturbation under unplanned condition compared with copers and controls. Current data suggest that altered reactive joint kinematics under the unanticipated condition in CAI patients may contribute to the condition of CAI after ankle sprains. Clinicians should focus on rehabilitation programs to recover and/or develop feedback control for CAI patients during functional movements under unanticipated condition to prevent further injuries.


Asunto(s)
Traumatismos del Tobillo , Inestabilidad de la Articulación , Humanos , Tobillo , Fenómenos Biomecánicos , Articulación del Tobillo , Extremidad Inferior , Enfermedad Crónica
13.
Scand J Med Sci Sports ; 33(7): 1125-1134, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36780246

RESUMEN

BACKGROUND: Limited dorsiflexion range of motion (DFROM) is a risk factor for lateral ankle sprain. However, varied DFROM exists within the chronic ankle instability (CAI) population, and how the variability may influence altered movement patterns during landing is unclear. OBJECTIVE: The purpose of this study was to identify different movement strategies during maximal jump landing/cutting among CAI patients classified by varied DFROM. METHODS: One hundred CAI subjects were classified into 3 subgroups based on their DFROM, measured by the weight-bearing lunge test: a Hypo- (≤40°), Normal- (40-50°), and Hyper-DFROM group (≥50°). Participants completed five trials of maximal jump landing/cutting. Lower extremity joint angles and EMG activation of seven muscles were collected from initial contact to toe-off. Functional analyses of variance were used to evaluate between-group differences for these outcome variables. RESULTS: Hypo-DFROM group (14M, 10F) displayed the reduced ankle dorsiflexion and inversion angles with increased hip flexion angle as a compensatory kinematic chain movement strategy. In addition, motion restrictions of the ankle are associated with altered muscle activation in both distal and proximal muscles during landing/cutting. Normal-DFROM (25M, 30F) and Hyper-DFROM (11M, 10F) groups also have different movement strategies including greater inversion angle and less EMG activation, which could contribute to further ankle injuries. CONCLUSIONS: Our data suggest that limited DFROM negatively affects the ankle joint during demanding movement within the CAI population. These movement patterns in CAI patients with pathomechanical deficits could contribute to further ankle sprains.


Asunto(s)
Traumatismos del Tobillo , Inestabilidad de la Articulación , Humanos , Tobillo , Fenómenos Biomecánicos , Extremidad Inferior , Articulación del Tobillo , Rango del Movimiento Articular/fisiología , Enfermedad Crónica
14.
Nano Lett ; 22(16): 6631-6636, 2022 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-35950996

RESUMEN

During the lithation of silicon anodes, the solid-state diffusion of lithium into LixSi follows the Arrhenius law, the resulting morphology and fracture behavior are determined by the silicon anode operation temperature. Here, we reveal the temperature dependence of the lithiation mechanics of crystalline silicon nanopillars (SiNPs) via microscopic observations of the anisotropic growth and fracture behavior. We fabricated 1D SiNP structures with various orientations (⟨100⟩, ⟨110⟩, and ⟨111⟩) as working electrodes and operated them at temperatures ranging from -20 to 40 °C. The lithiation of crystalline silicon at low temperatures exhibited preferential volume expansion along ⟨110⟩ and decreased fracture resistance. Furthermore, low temperatures caused the catastrophic fracture of amorphous silicon after the second lithiation. Our findings demonstrate the importance of silicon anode temperature control to prevent mechanical fracture during the cycle of lithium-ion batteries in harsh environments (e.g., electric vehicles in winter).

15.
Nano Lett ; 22(4): 1804-1811, 2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-34898226

RESUMEN

Transition metal layered oxides (LiNixCoyMn1-x-yO2, NCM) have been considered as one of the most promising cathodes for lithium-ion batteries used in long-mileage electric vehicles and energy storage systems. Despite its potential interest, dissolved transition metal (TM) ions toward anode sides can catalyze parasitic reactions such as electrolytic decomposition and dendritic Li growth, ultimately leading to catastrophic safety hazards. In this study, we demonstrate that Prussian Blue (PB) nanoparticles anchored to a commercial PE separator significantly reduce cell resistance and effectively suppress TM crossover during cycling, even under harsh conditions that accelerate Ni dissolution. Therefore, using a PB-coated separator in a harsh condition to intentionally dissolve Ni2+ ions at a high cutoff potential of 4.6 V, NCM||graphite full cells maintain 50.8% of their initial capacity at the 150th cycle. Scalable production of PB-coated separator through the facile synthetic methods can help establish a new research direction for the design of high-energy-density batteries.

16.
Nano Lett ; 22(18): 7423-7431, 2022 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-36044736

RESUMEN

We have designed and fabricated a TEM (transmission electron microscopy) liquid cell with hundreds of graphene nanocapsules arranged in a stack of two Si3N4-x membranes. These graphene nanocapsules are formed on arrays of nanoholes patterned on the Si3N4-x membrane by focused ion beam milling, allowing for better resolution than for the conventional graphene liquid cells, which enables the observation of light elements, such as atomic structures of silicon. We suggest that multiple nanocapsules provide opportunities for consecutive imaging under the same conditions in a single liquid cell. The use of single-crystal graphene windows offers an excellent signal-to-noise ratio and high spatial resolution. The motion of silicon nanoparticles (a low atomic number (Z) material) interacting with nanobubbles was observed, and analyzed, in detail. Our approach will help advance liquid-phase TEM observations by providing a straightforward method to encapsulate liquid between monolayers of various 2-dimensional materials.


Asunto(s)
Grafito , Nanocápsulas , Nanopartículas , Grafito/química , Microscopía Electrónica de Transmisión , Nanopartículas/química , Silicio
17.
Nano Lett ; 22(21): 8509-8518, 2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36315593

RESUMEN

Lithium metal batteries (LMBs) will be a breakthrough in automotive applications, but they require the development of next-generation solid-state electrolytes (SSEs) to stabilize the anode interface. Polymer-in-ceramic PEO/TiO2 nanocomposite SSEs show outstanding properties, allowing unprecedented LMBs durability and self-healing capabilities. However, the mechanism underlying the inhibition/delay of dendrite growth is not well understood. In fact, the inorganic phase could act as both a chemical and a mechanical barrier to dendrite propagation. Combining advanced in situ and ex situ experimental techniques, we demonstrate that oligo(ethylene oxide)-capped TiO2, although chemically inert toward lithium metal, imparts SSE with mechanical and dynamical properties particularly favorable for application. The self-healing characteristics are due to the interplay between mechanical robustness and high local polymer mobility which promotes the disruption of the electric continuity of the lithium dendrites (razor effect).

18.
Angew Chem Int Ed Engl ; 62(48): e202312928, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-37842904

RESUMEN

High-capacity Li-rich layered oxides using oxygen redox as well as transition metal redox suffer from its structural instability due to lattice oxygen escaped from its structure during oxygen redox and the following electrolyte decomposition by the reactive oxygen species. Herein, we rescued a Li-rich layered oxide based on 4d transition metal by employing an organic superoxide dismutase mimics as a homogeneous electrolyte additive. Guaiacol scavenged superoxide radicals via dismutation or disproportionation to convert two superoxide molecules to peroxide and dioxygen after absorbing lithium superoxide on its partially negative oxygen of methoxy and hydroxyl groups. Additionally, guaiacol was decomposed to form a thin and stable cathode-electrolyte interphase (CEI) layer, endowing the cathode with the interfacial stability.

19.
Angew Chem Int Ed Engl ; 62(42): e202309852, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37635684

RESUMEN

Conventional solid electrolyte frameworks typically consist of anions such as sulphur, oxygen, chlorine, and others, leading to inherent limitations in their properties. Despite the emergence of sulphide, oxide, and halide-based solid electrolytes for all-solid-state batteries, their utilization is hampered by issues, including the evolution of H2 S gas, the need for expensive elements, and poor contact. Here, we first introduce Prussian Blue analogue (PBA) open-framework structures as a solid electrolyte that demonstrates appreciable Na+ conductivity (>10-2 mS cm-1 ). We delve into the relationship between Na+ conductivity and the lattice parameter of N-coordinated transition metal, which is attributed to the reduced interaction between Na+ and the framework, corroborated by the distribution of relaxation times and density functional theory calculations. Among the five PBAs studied, Mn-PBA have exhibited the highest Na+ conductivity of 9.1×10-2 mS cm-1 . Feasibility tests have revealed that Mn-PBA have maintained a cycle retention of 95.1 % after 80cycles at 30 °C and a C-rate of 0.2C. Our investigation into the underlying mechanisms that play a significant role in governing the conductivity and kinetics of these materials contributes valuable insights for the development of alternative strategies to realize all-solid-state batteries.

20.
Semin Cancer Biol ; 76: 99-109, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34058338

RESUMEN

Nickel compounds are environmental toxicants, prevalent in the atmosphere due to their widespread use in several industrial processes, extensive consumption of nickel containing products, as well as burning of fossil fuels. Exposure to nickel is associated with a multitude of chronic inflammatory lung diseases including asthma, chronic obstructive pulmonary disease (COPD) and pulmonary fibrosis. In addition, nickel exposure is implicated in the development of nasal and lung cancers. Interestingly, a common pathogenic mechanism underlying the development of diseases associated with nickel exposure is epithelial-mesenchymal transition (EMT). EMT is a process by which the epithelial cells lose their junctions and polarity and acquire mesenchymal traits, including increased ability to migrate and invade. EMT is a normal and essential physiological process involved in differentiation, development and wound healing. However, EMT also contributes to a number of pathological conditions, including fibrosis, cancer and metastasis. Growing evidence suggest that EMT induction could be an important outcome of nickel exposure. In this review, we discuss the role of EMT in nickel-induced lung diseases and the mechanisms associated with EMT induction by nickel exposure.


Asunto(s)
Transición Epitelial-Mesenquimal/efectos de los fármacos , Enfermedades Pulmonares/inducido químicamente , Enfermedades Pulmonares/patología , Níquel/efectos adversos , Animales , Humanos
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