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1.
Small ; 20(3): e2304892, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37691021

RESUMEN

Layered indium selenide (InSe) is a new 2D semiconductor material with high carrier mobility, widely adjustable bandgap, and high ductility. However, its ion storage behavior and related electrochemical reaction mechanism are rarely reported. In this study, InSe nanoflakes encapsulated in conductive polypyrrole (InSe@PPy) are designed in consideration of restraining the severe volume change in the electrochemical reaction and increasing conductivity via in situ chemical oxidation polymerization. Density functional theory calculations demonstrate that the construction of heterostructure can generate an internal electric field to accelerate electron transfer via additional driving forces, offering synergistically enhanced structural stability, electrical conductivity, and Na+ diffusion process. The resulting InSe@PPy composite shows outstanding electrochemical performance in the sodium ion batteries system, achieving a high reversible capacity of 336.4 mA h g-1 after 500 cycles at 1 A g-1 and a long-term cyclic stability with capacity of 274.4 mA h g-1 after 2800 cycles at 5 A g-1 . In particular, the investigation of capacity fluctuation within the first cycling reveals the alternating significance of intercalation and conversion reactions and evanescent alloying reaction. The combined reaction mechanism of insertion, conversion, and alloying of InSe@PPy is revealed by in situ X-ray diffraction, ex situ electrochemical impedance spectroscopy, and transmission electron microscopy.

2.
Langmuir ; 40(26): 13467-13475, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38889438

RESUMEN

Because of the deep and zigzag microporous structure, porous carbon materials exhibit inferior capacitive performance and sluggish electrochemical kinetics for supercapacitor electrode materials. Herein, a single-step carbonation and activation approach was utilized to synthesize coal-based porous carbon with an adjustable pore structure, using CaO as a hard template, KOH as an activator, and oxidized coal as precursors to carbon. The obtained sample possesses an interconnected and hierarchical porous structure, higher SSA (1060 m2 g-1), suitable mesopore volume (0.25 cm3 g-1), and abundant surface heteroatomic functional groups. Consequently, the synthesized carbon exhibits an exceptionally high specific capacitance of 323 F g-1 at 1 A g-1, along with 80.3% capacitance retention at 50 A g-1. The assembled two-electrode configuration demonstrates a remarkable capacitance retention of up to 95% and achieves Coulombic efficiency of nearly 100% with 10,000 cycles in a 6 M KOH electrolyte. Furthermore, the Zn-ion hybrid capacitor also exhibits a specific capacity of up to 139.1 mA h g-1 under conditions of 0.2 A g-1. This work offers a simple method in preparation of coal-based porous carbon with controllable pore structure.

3.
PLoS Genet ; 17(8): e1009693, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34351909

RESUMEN

The ubiquitin-proteasome system plays important roles in various biological processes as it degrades the majority of cellular proteins. Adequate proteasomal degradation of crucial transcription regulators ensures the proper development of neutrophils. The ubiquitin E3 ligase of Growth factor independent 1 (GFI1), a key transcription repressor governing terminal granulopoiesis, remains obscure. Here we report that the deficiency of the ring finger protein Interferon regulatory factor 2 binding protein 2a (Irf2bp2a) leads to an impairment of neutrophils differentiation in zebrafish. Mechanistically, Irf2bp2a functions as a ubiquitin E3 ligase targeting Gfi1aa for proteasomal degradation. Moreover, irf2bp2a gene is repressed by Gfi1aa, thus forming a negative feedback loop between Irf2bp2a and Gfi1aa during neutrophils maturation. Different levels of GFI1 may turn it into a tumor suppressor or an oncogene in malignant myelopoiesis. Therefore, discovery of certain drug targets GFI1 for proteasomal degradation by IRF2BP2 might be an effective anti-cancer strategy.


Asunto(s)
Proteínas de Unión al ADN/genética , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteínas de Pez Cebra/metabolismo , Pez Cebra/crecimiento & desarrollo , Animales , Proteínas de Unión al ADN/metabolismo , Retroalimentación Fisiológica , Femenino , Regulación de la Expresión Génica , Técnicas de Inactivación de Genes , Células HEK293 , Células HL-60 , Humanos , Leucopoyesis , Masculino , Proteolisis , Pez Cebra/genética , Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética
4.
Ann Hematol ; 102(5): 1131-1140, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36947212

RESUMEN

Pediatric-inspired chemotherapy significantly improves survival for adolescent and adult patients with acute lymphoblastic leukemia (ALL). However, the benefits over allogeneic hematopoietic stem cell transplantation (allo-HSCT) remain unclear. To compare clinical outcomes between pediatric-inspired chemotherapy and allo-HSCT in consolidation therapy of adolescent and adult Philadelphia chromosome-negative (Ph-neg) ALL in first complete remission (CR1), related studies from MEDLINE, Embase, and Cochrane Controlled Register of Trials updated to July 2022 were searched. A total of 13 relevant trials including 3161 patients were included in the meta-analysis. Compared with allo-HSCT, pediatric-inspired chemotherapy achieved better OS (hazard risk (HR), 0.53; 95% confidence interval (CI), 0.41 to 0.68) and DFS (HR, 0.64; 95% CI, 0.48 to 0.86), with a significant reduction in NRM (risk ratio (RR), 0.30; 95% CI, 0.18 to 0.51), but no difference in the relapse rate (RR, 1.13; 95% CI, 0.93 to 1.39). When only studies based on intention-to-treat analysis were included, pediatric-inspired chemotherapy consistently conferred a survival advantage. In subgroup analyses, patients with baseline high-risk features demonstrated similar OS and DFS between pediatric-style chemotherapy and allo-HSCT, while pediatric-style chemotherapy had an OS and DFS advantage in standard-risk subgroup. Particularly, patients with positive minimal residual disease (MRD) achieved better OS and DFS if proceeded to allo-HSCT.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Adulto , Adolescente , Cromosoma Filadelfia , Inducción de Remisión , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Enfermedad Aguda , Estudios Retrospectivos
5.
Langmuir ; 39(9): 3371-3379, 2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36809001

RESUMEN

In this paper, g-C3N4-based hydrogel with a 3D network structure was synthesized via a simple and cheap reaction, using hydroxyethyl cellulose (HEC) and graphitic carbon nitride (g-C3N4) as the main materials. Electron microscope images revealed that the microstructure of g-C3N4-HEC hydrogel was rough and porous. The luxuriant scaly textures of this hydrogel were due to the uniform distribution of g-C3N4 nanoparticles. It was found that this hydrogel showed great removal ability of bisphenol A (BPA) through a synergistic effect of adsorption and photodegradation. The adsorption capacity and degradation efficiency of g-C3N4-HEC hydrogel (3%) for BPA were 8.66 mg/g and 78% under the conditions of C0 = 9.94 mg/L and pH = 7.0, which were much higher than those for the original g-C3N4 and HEC hydrogel. In addition, g-C3N4-HEC hydrogel (3%) exhibited excellent removal efficiency (98%) of BPA (C0 = 9.94 mg/L) in a dynamic adsorption and photodegradation system. Meanwhile, the mechanism of removal was investigated in depth. The superior batch and continuous removal capability of this g-C3N4-based hydrogel make it promising for environmental applications.

6.
Langmuir ; 39(19): 6865-6873, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37133428

RESUMEN

Porous carbon, one of the characteristic materials for electrochemical energy storage devices, has been paid wide-ranging attention. However, balancing the reconcilable mesopore volume with a large specific surface area (SSA) was still a challenge. Herein, a dual-salt-induced activation strategy was developed to obtain a porous carbon sheet with ultrahigh SSA (3082 m2 g-1), desirable mesopore volume (0.66 cm3 g-1), nanosheet morphology, and high surface O (7.87%) and S (4.0%) content. Hence, as a supercapacitor electrode, the optimal sample possessed a high specific capacitance (351 F g-1 at 1 A g-1) and excellent rate performance (holding capacitance up to 72.2% at 50 A g-1). Furthermore, the assembled zinc-ion hybrid supercapacitor also exhibited superior reversible capacity (142.7 mAh g-1 at 0.2 A g-1) and highly stable cycling (71.2 mAh g-1 at 5 A g-1 after 10,000 cycles with retention of 98.9%). This work was delivered a new possibility for the development of coal resources for the preparation of high performance porous carbon materials.

7.
Langmuir ; 39(49): 18073-18081, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38014689

RESUMEN

The defective BiOCl nanosheet exposed (001) facet with favorable photocatalytic performance was designed. The surface microstructure analysis and theoretical calculation certified the dominant exposed (001) facet and rich surface oxygen defects of Br--doped BiOCl (B-6) nanosheets. The energy level structure analysis indicates that the band gap can be narrowed and the light absorption range can be widened by introducing Br- to BiOCl, and the presence of defective energy levels increases the photogenerated carrier transfer efficiency. Moreover, the doping of Br- in BiOCl promotes the directional flow of electrons to the surface of B-6, which improves the photocatalytic performance of the sample. Thus, the Br--doped BiOCl can degrade 96.5% RhB within 6 min under visible-light irradiation with high apparent reaction rate constants of 0.51 min-1, exhibiting the strongest photocatalytic degradation performance. This work provides guidance for the preparation of Bi-based photocatalysts with excellent performance.

8.
Molecules ; 28(13)2023 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-37446628

RESUMEN

To reduce the issue of tri-primary color reabsorption, a new approach for single-phase phosphors as light-emitting diodes (LEDs) has been recommended. The structures, morphology, photoluminescence, thermal stability, and luminescence mechanism of a variety of Ca3Bi (PO4)3 (CBPO): Ce3+/Dy3+ phosphors were investigated. XRD characterization showed that all CBPO samples were eulytite structures. Furthermore, the energy transfer process from Ce3+ to Dy3+ in CBPO is systematically investigated in this work, and the color of light can be adjusted by changing the ratio of doped ions. Under UV light, energy is transferred from Ce3+-Dy3+ mainly through quadrupole-quadrupole interactions in the CBPO host, and doping with different Dy3+ concentrations tunes the emission color from blue to white. The thermal stability of the CBPO: 0.04Ce3+, 0.08Dy3+ samples is outstanding, and the CIE coordinates of the samples after emission have little effect with temperature, while their emission intensity at 423 K is as strong as that at room temperature, reaching 90%. The above results indicate that this CBPO material has great potential as a white light phosphor under near-UV excitation at the optimized concentration of Ce3+ and Dy3+.


Asunto(s)
Disprosio , Luminiscencia , Disprosio/química , Rayos Ultravioleta , Transferencia de Energía , Temperatura
9.
Molecules ; 28(15)2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37570678

RESUMEN

In this work, Qiqunahu (QQH) coal, cotton stalk, cellulose and lignin extracted from cotton stalk were selected as raw materials to study the effects of the co-pyrolysis of coal and cotton stalk. Online thermogravimetric mass spectrometry (TG-MS) was used to analyse mass loss and gas release characteristics during co-pyrolysis. The results reveal that the mixture of cotton stalk and coal can significantly enhance the reactivity of the blends and promote the formation of effective gas. The cellulose in the cotton stalk promotes the generation of H2 and CO2 during the co-pyrolysis of coal and cotton stalks. Lignin promotes the production of CH4 and CO2. Cellulose and lignin show an inhibitory effect on the precipitation of small molecular weight hydrocarbon gases during co-pyrolysis. This study provides a better understanding for the co-pyrolysis of biomass and coal.

10.
Molecules ; 28(9)2023 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-37175070

RESUMEN

The surface properties and the hierarchical pore structure of carbon materials are important for their actual application in supercapacitors. It is important to pursue an integrated approach that is both easy and cost-effective but also challenging. Herein, coal-based hierarchical porous carbon with nitrogen doping was prepared by a simple dual template strategy using coal as the carbon precursor. The hierarchical pores were controlled by incorporating different target templates. Thanks to high conductivity, large electrochemically active surface area (483 m2 g-1), hierarchical porousness with appropriate micro-/mesoporous channels, and high surface nitrogen content (5.34%), the resulting porous carbon exhibits a high specific capacitance in a three-electrode system using KOH electrolytes, reaching 302 F g-1 at 1 A g-1 and 230 F g-1 at 50 A g-1 with a retention rate of 76%. At 250 W kg-1, the symmetrical supercapacitor assembled at 6 M KOH shows a high energy density of 8.3 Wh kg-1, and the stability of the cycling is smooth. The energy density of the symmetric supercapacitor assembled under ionic liquids was further increased to 48.3 Wh kg-1 with a power output of 750 W kg-1 when the operating voltage was increased to 3 V. This work expands the application of coal-based carbon materials in capacitive energy storage.

11.
Haematologica ; 105(2): 325-337, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31123027

RESUMEN

Aproper choice of neutrophil-macrophage progenitor cell fate is essential for the generation of adequate myeloid subpopulations during embryonic development and in adulthood. The network governing neutrophil-macrophage progenitor cell fate has several key determinants, such as myeloid master regulators CCAAT enhancer binding protein alpha (C/EBPα) and spleen focus forming virus proviral integration oncogene (PU.1). Nevertheless, more regulators remain to be identified and characterized. To ensure balanced commitment of neutrophil-macrophage progenitors toward each lineage, the interplay among these determinants is not only synergistic, but also antagonistic. Depletion of interferon regulatory factor 2 binding protein 2b (Irf2bp2b), a well-known negative transcription regulator, results in a bias in neutrophil-macrophage progenitor cell fate in favor of macrophages at the expense of neutrophils during the stage of definitive myelopoiesis in zebrafish embryos. Mechanistic studies indicate that Irf2bp2b acts as a downstream target of C/EBPα, repressing PU.1 expression, and that SUMOylation confers the repressive function of Irf2bp2b. Thus, Irf2bp2b is a novel determinant in the choice of fate of neutrophil-macrophage progenitor cells.


Asunto(s)
Proteínas de Unión al ADN/genética , Mielopoyesis , Factores de Transcripción/genética , Proteínas de Pez Cebra/genética , Pez Cebra , Animales , Proteínas Portadoras , Diferenciación Celular , Macrófagos , Neutrófilos
12.
FASEB J ; 32(9): 4930-4940, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29634367

RESUMEN

RING finger protein 4 (RNF4) is a multifunctional small ubiquitin-related modifier (SUMO)-targeted ubiquitin E3 ligase (STUbL) ubiquitously expressed in all tissues, and which mainly participates in DNA repair and in chromatin and transcriptional regulation. Although RNF4 has been implicated in hematopoietic disorders, its ontogenic role during hematopoietic development remains undiscovered. We generated a zebrafish rnf4 knockout line by using transcription activator-like effector nucleases technology to address the impact of rnf4 during hematopoiesis. Rnf4-deficient zebrafish embryos exhibited sharply decreased neutrophils numbers during both primitive and definitive hematopoiesis. Mechanistic studies revealed that repression of the key granulocytic activator, CCAAT/enhancer-binding protein α ( c/ebpα), via promoter hypermethylation by SUMOylated DNA methyltransferase 1 (DNMT1) was the main cause of impaired granulopoiesis in rnf4-deficient zebrafish. In addition, for the first time, we identified DNMT1 as a potential new STUbL substrate of RNF4, with knockdown of dnmt1 largely restoring primitive and definitive granulopoiesis in rnf4-deficient zebrafish. Collectively, RNF4 is indispensable for zebrafish granulopoiesis through regulation of the DNMT1-C/EBPα functional axis.-Wang, L., Liu, X., Wang, H., Yuan, H., Chen, S., Chen, Z., de The, H., Zhou, J., Zhu, J. RNF4 regulates zebrafish granulopoiesis through the DNMT1-C/EBPα axis.


Asunto(s)
ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , Regulación de la Expresión Génica/genética , Mutación/genética , Proteínas Nucleares/genética , Proteína SUMO-1/metabolismo , Factores de Transcripción/genética , Proteínas de Pez Cebra/metabolismo , Animales , Proteína alfa Potenciadora de Unión a CCAAT/metabolismo , ADN (Citosina-5-)-Metiltransferasa 1/genética , Reparación del ADN/genética , Hematopoyesis/genética , Humanos , Proteína SUMO-1/genética , Sumoilación/genética , Sumoilación/fisiología , Factores de Transcripción/metabolismo , Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética
13.
Chemistry ; 22(7): 2339-44, 2016 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-26751009

RESUMEN

Nitrogen-doped mesoporous hollow carbon spheres (NHCS) consisting of hybridized amorphous and graphitic carbon were synthesized by chemical vapor deposition with pitch as raw material. Treatment with HNO3 vapor was performed to incorporate oxygen-containing groups on NHCS, and the resulting NHCS-O showed excellent rate capacity, high reversible capacity, and excellent cycling stability when tested as the anode material in lithium-ion batteries. The NHCS-O electrode maintained a reversible specific capacity of 616 mAh g(-1) after 250 cycles at a current rate of 500 mA g(-1) , which is an increase of 113 % compared to the pristine hollow carbon spheres. In addition, the NHCS-O electrode exhibited a reversible capacity of 503 mAh g(-1) at a high current density of 1.5 A g(-1) . The superior electrochemical performance of NHCS-O can be attributed to the hybrid structure, high N and O contents, and rich surface defects.

14.
Phys Chem Chem Phys ; 17(43): 28802-8, 2015 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-26451398

RESUMEN

A series of Ce(3+)/Tb(3+) co-doped MgZn2(PO4)2 phosphors have been synthesized by the co-precipitation method. Their structure, morphology, photoluminescence properties, decay lifetime, thermal stability and luminous efficiency were investigated. The possible energy transfer mechanism was proposed based on the experimental results and detailed luminescence spectra and decay curves of the phosphors. The critical distance between Ce(3+) and Tb(3+) ions was calculated by both the concentration quenching method and the spectral overlap method. The energy transfer mechanism from the Ce(3+) to Tb(3+) ion was determined to be dipole-quadrupole interaction, and the energy transfer efficiency was 85%. By utilizing the principle of energy transfer and appropriate tuning of Ce(3+)/Tb(3+) contents, the emission color of the obtained phosphors can be tuned from blue to green light. The MgZn2(PO4)2:Ce(3+),Tb(3+) phosphor is proved to be a promising UV-convertible material capable of green light emitting in UV-LEDs due to its excellent thermal stability and luminescence properties.

15.
Int J Biol Macromol ; 260(Pt 2): 129570, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38246456

RESUMEN

Sodium lignosulfonate, an abundant natural resource, is regarded as an ideal precursor for the synthesis of hard carbon. The development of high-performance, low-cost and sustainable anode materials is a significant challenge facing lithium-ion batteries (LIBs). The modulation of morphology and defect structure during thermal transformation is crucial to improve Li+ storage behavior. Synthesized using sodium lignosulfonate as a precursor, two-dimensional carbon nanosheets with a high density of defects were produced. The synergistic influence of ice templates and KCl was leveraged, where the ice prevented clumping of potassium chloride during drying, and the latter served as a skeletal support during pyrolysis. This resulted in the formation of an interconnected two-dimensional nanosheet structure through the combined action of both templates. The optimized sample has a charging capacity of 712.4 mA h g-1 at 0.1 A g-1, which is contributed by the slope region. After 200 cycles at 0.2 A g-1, the specific charge capacity remains 514.4 mA h g-1, and a high specific charge capacity of 333.8 mA h g-1 after 800 cycles at 2 A g-1. The proposed investigation offers a promising approach for developing high-performance, low-cost carbon-based anode materials that could be used in advanced lithium-ion batteries.


Asunto(s)
Hielo , Lignina/análogos & derivados , Litio , Cristalización , Carbono
16.
Clin Exp Med ; 24(1): 22, 2024 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-38280072

RESUMEN

The quality of immune reconstitution (IR) is crucial for the outcome of patients who received allogeneic hematopoietic stem cell transplantation (allo-HSCT), and is closely connected with infection, relapse and graft-versus-host disease (GvHD) which are the most important causes for transplantation failure. However, the IR pattern in the early stage after allo-HSCT, particularly haploidentical (HID) HSCT, remains unclear. In this retrospective study, we examined the T cell reconstitution of patients within the initial 30 days (n = 173) and 100 days (n = 122) after allo-HSCT with myeloablative condition (MAC), of which > 70% were HID HSCT, to assess the influence of IR on the transplant outcomes. By comparing 78 patients with good IR (GIR) to 44 patients with poor IR (PIR), we observed that GIR was associated with lower risk for Epstein-Barr virus (EBV) reactivation and cytomegalovirus (CMV) reactivation, but had no significant impacts on the survival outcomes (i.e., overall survival, event-free survival) and cumulative incidences of GvHD. Importantly, we found lymphocyte reconstitution pattern at day 30 after allo-HSCT would be a surrogate for IR evaluated at day 100. In the Cox proportional hazard model, early reconstitution of CD4+, CD4+CD25+, CD4+CD45RO+, CD4+CD25+CD27low, and CD8+ T cells at day 30 was reversely correlated with risk of EBV reactivation. Finally, we constructed a predictive model for EBV reactivation with CD8+ and CD4+CD45RO+ T cell proportions of the training cohort (n = 102), which was validated with a validation cohort (n = 37). In summary, our study found that the quality of IR at day 30 had a predictive value for the risk of EBV reactivation, and might provide guidance for close monitoring for EBV reactivation.


Asunto(s)
Infecciones por Citomegalovirus , Infecciones por Virus de Epstein-Barr , Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Humanos , Herpesvirus Humano 4 , Linfocitos T CD8-positivos , Citomegalovirus , Estudios Retrospectivos , Trasplante Homólogo/efectos adversos , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Enfermedad Injerto contra Huésped/complicaciones
17.
Int J Biol Macromol ; 262(Pt 2): 130254, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38368992

RESUMEN

The developed porous structure and high density are essential to enhance the bulk performance of carbon-based supercapacitors. Nevertheless, it remains a significant challenge to optimize the balance between the porous structure and the density of carbon materials to realize superior gravimetric and areal electrochemical performance. The soluble starch-derived interconnected hierarchical porous carbon microspheres were prepared through a simple hydrothermal treatment succeeded by chemical activation with a low dosage of KOH. Due to the formation of interconnected spherical morphology, hierarchical porous structure, reasonable mesopore volume (0.33 cm3 g-1) and specific surface area (1162 m2 g-1), the prepared carbon microsphere has an ultrahigh capacitance of 394 F g-1 @ 1 A g-1 and a high capacitance retention of 62.7 % @ 80 A g-1. The assembled two-electrode device displays good cycle stability after 20,000 cycles and an ultra-high energy density of 11.6 Wh kg-1 @ 250 W kg-1. Moreover, the sample still exhibits a specific capacitance of 165 F g-1 @ 1 A g-1 at a high mass loading of 10 mg cm-2, resulting in a high areal capacitance of 1.65 F cm-2. The strategy proposed in this study, via a low-dose KOH activation process, provides the way for the synthesis of high-performance porous carbon materials.


Asunto(s)
Carbono , Almidón , Carbono/química , Microesferas , Porosidad , Capacidad Eléctrica
18.
Blood Sci ; 6(2): e00183, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38283406

RESUMEN

Data on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in patients at early stage of immune reconstitution after hematopoietic stem cell transplantation (HSCT) are limited. In the present study, we retrospectively investigated the incidence and clinical features of SARS-CoV-2 infection in patients who underwent HSCT in 2022. Patients (allo-HSCT, n = 80; auto-HSCT, n = 37) were consecutively included in the study. The SARS-CoV-2 infection rate was 59.8%, and the median interval of HSCT to coronavirus disease 2019 (COVID-19) was 4.8 (range: 0.5-12) months. Most patients were categorized as mild (41.4%) or moderate (38.6%), and 20% as severe/critical. No deaths were attributable to COVID-19. Further analysis showed that lower circulating CD8+ T-cell counts and calcineurin inhibitor administration increased the risk of SARS-CoV-2 infection. Exposure to rituximab significantly increased the probability of severe or critical COVID-19 compared with that of mild/moderate illness (P < .001). In the multivariate analysis, rituximab use was associated with severe COVID-19. Additionally, COVID-19 had no significant effect on immune reconstitution. Furthermore, it was found that Epstein-Barr virus infection and rituximab administration possibly increase the risk of developing severe illness. Our study provides preliminary insights into the effect of SARS-CoV-2 on immune reconstitution and the outcomes of allo-HSCT recipients.

19.
J Colloid Interface Sci ; 665: 846-854, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38564948

RESUMEN

The unique superconductivity and charge density wave transition characteristics of NbSe2 make it worthy of exploring its electrochemical performance and potential applications in the field of batteries. Herein, the bulk NbSe2 was successfully exfoliated into few-layered NbSe2 nanostructures by wet grinding exfoliation approach, which solved the issues of its long activation period and poor cycle stability. The strong Nb-Se bond in the plane and weak van der Waals force between the adjacent layers could render the fast Na+ diffusion, provide abundant reaction sites and multi-directional migration paths, thus accelerate the ionic conductivity. The theoretical calculations verified the high Na+ adsorption tendency between the NbSe2 interlayers stemming from the continuous region of charge accumulation. Thanks to the unique electronic and two-dimensional few-layered structures, the exfoliated NbSe2 exhibited a high cyclic stability with a capacity of 502 mA h g-1 over 2800 cycles at 10 A/g. In addition, the reaction mechanism was studied by in-situ X-ray diffraction and other tests, indicating a reaction mechanism containing of simultaneous intercalation (NbSe2↔NaxNbSe2↔NaNbSe2↔Na1+xNbSe2) and conversion processes in NbSe2. This parallelly running mechanism not only alleviates the volume change but also ensures a high specific capacity. Additionally, different lattice planes of the NaNbSe2 intermediate in the intercalation process experience varying degrees of contraction and expanding in d-spacing due to the influence of Coulombic force.

20.
J Colloid Interface Sci ; 671: 589-600, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38820843

RESUMEN

Coal-based oxygen electrocatalysts hold immense promise for cost-effective applications in rechargeable Zn-air batteries (ZABs) and the value-added, clean utilization of traditional coal resources. Herein, an electrospun membrane electrode comprising coal-derived carbon nanosheets and directly grown carbon nanotubes (CNS/CMF@CNT) was successfully synthesized. The hierarchical porous structure of the electrode, composed of multiple components, significantly facilitates mass and ion transportation, resulting in exceptional electrochemical performance. Employing Fe as the catalyst for CNT growth, the CNS/CMF@CNT electrode exhibits a remarkable onset potential of 0.96 V and a half-wave potential of 0.87 V in the oxygen reduction reaction (ORR). In-situ surface-enhanced Raman spectroscopy reveals that hydroxyl radical desorption on the surface of CNS/CMF@CNT(Fe) is the rate-determining step of the ORR. Notably, the aqueous ZAB featuring the CNS/CMF@CNT(Fe) electrode achieved a peak power density of 216.0 mW cm-2 at a current density of 414 mA cm-2 and maintained a voltage efficiency of 65.1 % after 2000 charge/discharge cycles at 5 mA cm-2. Furthermore, the all-solid-state ZAB incorporating this electrode displayed an open-circuit voltage of 1.43 V, a peak power density of 70.1 mW cm-2 at a current density of 110 mA cm-2, and a voltage efficiency of 66.5 % after 150 charge/discharge cycles. The utilization of abundant coal as the raw material for electrode fabrication not only brings conceivable economic benefits in ZAB construction, but also commendably advances the effective application of traditional coal resources in a more sustainable manner.

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