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1.
Blood ; 142(15): 1297-1311, 2023 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-37339580

RESUMO

Anaplastic large cell lymphoma (ALCL), a subgroup of mature T-cell neoplasms with an aggressive clinical course, is characterized by elevated expression of CD30 and anaplastic cytology. To achieve a comprehensive understanding of the molecular characteristics of ALCL pathology and to identify therapeutic vulnerabilities, we applied genome-wide CRISPR library screenings to both anaplastic lymphoma kinase positive (ALK+) and primary cutaneous (pC) ALK- ALCLs and identified an unexpected role of the interleukin-1R (IL-1R) inflammatory pathway in supporting the viability of pC ALK- ALCL. Importantly, this pathway is activated by IL-1α in an autocrine manner, which is essential for the induction and maintenance of protumorigenic inflammatory responses in pC-ALCL cell lines and primary cases. Hyperactivation of the IL-1R pathway is promoted by the A20 loss-of-function mutation in the pC-ALCL lines we analyze and is regulated by the nonproteolytic protein ubiquitination network. Furthermore, the IL-1R pathway promotes JAK-STAT3 signaling activation in ALCLs lacking STAT3 gain-of-function mutation or ALK translocation and enhances the sensitivity of JAK inhibitors in these tumors in vitro and in vivo. Finally, the JAK2/IRAK1 dual inhibitor, pacritinib, exhibited strong activities against pC ALK- ALCL, where the IL-1R pathway is hyperactivated in the cell line and xenograft mouse model. Thus, our studies revealed critical insights into the essential roles of the IL-1R pathway in pC-ALCL and provided opportunities for developing novel therapeutic strategies.


Assuntos
Linfoma Anaplásico de Células Grandes , Linfoma Anaplásico Cutâneo Primário de Células Grandes , Neoplasias Cutâneas , Humanos , Animais , Camundongos , Linfoma Anaplásico de Células Grandes/tratamento farmacológico , Linfoma Anaplásico de Células Grandes/genética , Linfoma Anaplásico de Células Grandes/patologia , Receptores Proteína Tirosina Quinases/genética , Quinase do Linfoma Anaplásico/genética , Interleucinas/metabolismo
2.
J Am Chem Soc ; 146(11): 7295-7304, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38364093

RESUMO

All-weather operation is considered an ultimate pursuit of the practical development of sodium-ion batteries (SIBs), however, blocked by a lack of suitable electrolytes at present. Herein, by introducing synergistic manipulation mechanisms driven by phosphorus/silicon involvement, the compact electrode/electrolyte interphases are endowed with improved interfacial Na-ion transport kinetics and desirable structural/thermal stability. Therefore, the modified carbonate-based electrolyte successfully enables all-weather adaptability for long-term operation over a wide temperature range. As a verification, the half-cells using the designed electrolyte operate stably over a temperature range of -25 to 75 °C, accompanied by a capacity retention rate exceeding 70% even after 1700 cycles at 60 °C. More importantly, the full cells assembled with Na3V2(PO4)2O2F cathode and hard carbon anode also have excellent cycling stability, exceeding 500 and 1000 cycles at -25 to 50 °C and superb temperature adaptability during all-weather dynamic testing with continuous temperature change. In short, this work proposes an advanced interfacial regulation strategy targeted at the all-climate SIB operation, which is of good practicability and reference significance.

3.
Small ; 20(6): e2306195, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37789582

RESUMO

The poor reversibility and stability of Zn metal anode (ZMA) caused by uncontrolled Zn deposition behaviors and serious side reactions severely impeded the practical application of aqueous Zn metal battery. Herein, a liquid-dynamic and self-adaptive protective layer (LSPL) was constructed on the ZMA surface for inhibiting dendrites and by-products formation. Interestingly, the outer LSPL consists of liquid perfluoropolyether (PFPE), which can dynamically adapt volume change during repeat cycling and inhibit side reactions. Moreover, it can also decrease the de-solvation energy barrier of Zn2+ by strong interaction between C-F bond and foreign Zn2+ , improving Zn2+ transport kinetics. For the LSPL inner region, in-situ formed ZnF2 through the spontaneous chemical reaction between metallic Zn and part PFPE can establish an unimpeded Zn2+ migration pathway for accelerating ion transfer, thereby restricting Zn dendrites formation. Consequently, the LSPL-modified ZMA enables reversible Zn deposition/dissolution up to 2000 h at 1 mA cm-2 and high coulombic efficiency of 99.8% at 4 mA cm-2 . Meanwhile, LSPL@Zn||NH4 V4 O10 full cells deliver an ultralong cycling lifespan of 100 00 cycles with 0.0056% per cycle decay rate at 10 A g-1 . This self-adaptive layer provides a new strategy to improve the interface stability for next-generation aqueous Zn battery.

4.
Small ; 20(23): e2307464, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38212275

RESUMO

The transplantation of immunoisolated stem cell derived beta cell clusters (SC-ß) has the potential to restore physiological glycemic control in patients with type I diabetes. This strategy is attractive as it uses a renewable ß-cell source without the need for systemic immune suppression. SC-ß cells have been shown to reverse diabetes in immune compromised mice when transplanted as ≈300 µm diameter clusters into sites where they can become revascularized. However, immunoisolated SC-ß clusters are not directly revascularized and rely on slower diffusion of nutrients through a membrane. It is hypothesized that smaller SC-ß cell clusters (≈150 µm diameter), more similar to islets, will perform better within immunoisolation devices due to enhanced mass transport. To test this, SC-ß cells are resized into small clusters, encapsulated in alginate spheres, and coated with a biocompatible A10 polycation coating that resists fibrosis. After transplantation into diabetic immune competent C57BL/6 mice, the "resized" SC-ß cells plus the A10 biocompatible polycation coating induced long-term euglycemia in the mice (6 months). After retrieval, the resized A10 SC-ß cells exhibited the least amount of fibrosis and enhanced markers of ß-cell maturation. The utilization of small SC-ß cell clusters within immunoprotection devices may improve clinical translation in the future.


Assuntos
Células Secretoras de Insulina , Animais , Humanos , Células Secretoras de Insulina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Diabetes Mellitus Experimental , Células-Tronco/citologia , Células-Tronco/metabolismo , Diabetes Mellitus Tipo 1/terapia
5.
Fish Shellfish Immunol ; : 109843, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39181522

RESUMO

Takifugu obscurus is a farmed fish of great economic importance in China. The rapid development of T. obscurus aquaculture industry has been accompanied by disease and low temperature stress, resulting in huge economic losses. Cell lines are used extensively in teleost physiology and pathology as the most cost-effective platform for in vitro research. A novel gill cell line of T.obscurus (named TOG) was first successfully established, and passed through 52 generations. The optimal conditions for TOG growth were 20% FBS concentration and 24◦C, TOG could be grown in both hypotonic (150 mOsmol-kg-1) and hypertonic (600 mOsmol-kg-1) environments. TOG was determined to be derived from T.obscurus by sequencing the mitochondrial COI gene. Karyotype analysis revealed that the chromosome number of TOG was 44 (2n=44). Transfection experiment showed that TOG was able to express foreign genes. Furthermore, several immune-related genes were significantly up-regulated in TOG after LPS and poly (I:C) stimulation, including tlr3, isg15, il1ß and il10. Additionally, transcriptome analysis of TOG under low-temperature stress (24°C, 18°C, 12°C, 10°C and 8°C) found that differentially expressed genes (DEGs) were significantly clustered in several immunological and energy metabolic pathways, and cold stress could disrupt the immune barrier and reduce immunity by downregulating the immune-related pathways. Additionally, weighted gene co-expression network analysis (WGCNA) revealed that bule module and turquoise module, which were closely correlated with low temperature and the degree of fish damage, were both predominantly found in PPAR, NOD-like receptor and Toll-like receptor signaling pathway. Hub genes were identified in these two modules, including mre11, clpb, dhx15, ddx18 and utp15. TOG cell line will become an effective experimental platform for genetic and immunological researches, and our results would help us gain a deeper insight into the molecular mechanism of cold tolerance in teleost.

6.
Nanotechnology ; 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39163875

RESUMO

Phosphorene has been widely used as anode material for batteries. However, the huge volume change during charging and discharging process, the semiconductor properties, and the high open circuit voltage limit its application. Based on this, by introducing the electron-deficient boron atoms into blue phosphorene, we proposed a P-rich sandwich-like BP4 monolayer by density functional theory calculation and particle swarm optimization. The BP4 monolayer shows good thermodynamic and dynamic stability, as well as chemical stability in O2 atmosphere, mainly due to the strengthened P-P bond of the outer layer by the middle boron atoms adopting sp3 hybridization. According to the band structure, the BP4 monolayer shows metallic property, which is beneficial to electron conductivity. Furthermore, compared with blue phosphorene and black phosphorene, the P-rich BP4 monolayer shows higher theoretical capacity for Li, Na, and K of 1193.90, 1119.28, and 397.97 mA·h·g-1, respectively. The lattice constant of BP4 monolayer increases only 3.73 (Li), 2.52 (Na) after Li/Na fully adsorbed on the anode. More importantly, the wettability of BP4 monolayer in the electrolyte is comparable to that of graphene. These findings show that the stable sandwich-like BP4 monolayer has potential as a lightweight anode material.

7.
Phys Chem Chem Phys ; 26(7): 6208-6215, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38305386

RESUMO

Two-dimensional (2D) materials with light weight and ultra-high electrical conductivity are expected to exhibit high capacity as anodes of batteries. We have explored the curved square lattice BS2 (b-BS2) monolayer possessing a space group similar to the transition metal chloride (space group: P4̄M2). The electrochemical performance of the b-BS2 monolayer as the anode for various metal-ion batteries (Li, Na, K, Mg, Ca, and Al) has been investigated. It exhibits low diffusion energy barrier, high theoretical capacity, and low open circuit voltage for Na/K-ion batteries (SIBs/PIBs). The ultrahigh energy densities of 2146.08 and 715.36 mA h g-1 can be achieved with the stoichiometries BS2Na6 and BS2K2, respectively. Furthermore, the b-BS2 monolayer may be synthesized on the surfaces of metal substrate materials (Ag(111), Al(111), and Au(111)). These results indicate that the b-BS2 monolayer is a good candidate for the anode material of SIBs/PIBs.

8.
Support Care Cancer ; 32(3): 155, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38347229

RESUMO

PURPOSE: Sleep problems are a significant issue in patients with lung cancer, and resilience is a closely related factor. However, few studies have identified subgroups of resilience and their relationship with sleep quality. This study aimed to investigate whether there are different profiles of resilience in patients with lung cancer, to determine the sociodemographic characteristics of each subgroup, and to determine the relationship between resilience and sleep quality in different subgroups. METHODS: A total of 303 patients with lung cancer from four tertiary hospitals in China completed the General Sociodemographic sheet, the Connor-Davidson Resilience Scale, and the Pittsburgh Sleep Quality Index. Latent profile analysis was applied to explore the latent profiles of resilience. Multivariate logistic regression was used to analyze the sociodemographic variables in each profile, and ANOVA was used to explore the relationships between resilience profiles and sleep quality. RESULTS: The following three latent profiles were identified: the "high-resilience group" (30.2%), the "moderate-resilience group" (46.0%), and the "low-resilience group" (23.8%). Gender, place of residence, and average monthly household income significantly influenced the distribution of resilience in patients with lung cancer. CONCLUSION: The resilience patterns of patients with lung cancer varied. It is suggested that health care providers screen out various types of patients with multiple levels of resilience and pay more attention to female, rural, and poor patients. Additionally, individual differences in resilience may provide an actionable means for addressing sleep problems.


Assuntos
Neoplasias Pulmonares , Testes Psicológicos , Resiliência Psicológica , Transtornos do Sono-Vigília , Humanos , Feminino , Qualidade do Sono , Transtornos do Sono-Vigília/epidemiologia , Transtornos do Sono-Vigília/etiologia
9.
BMC Nurs ; 23(1): 523, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39085901

RESUMO

BACKGROUND: Promoting the work adaptation of nurses returning to work after childbirth is key to improving their physical and mental health and ensuring the quality of nursing care. Although postpartum nurses have reported high work stress and poor adaptation after returning to work, little is known regarding the experiences, problems and further needs. This study aimed to explore the adaptation experiences of postpartum nurses returning to work. METHODS: This was a qualitative study with descriptive phenomenological approach. Individual semi-structured interviews were conducted between March and May 2023 in four tertiary hospitals in Changsha, mainland China, which were selected using convenience sampling. A total of 16 postpartum nurses returning to work within one year were recruited using purposive sampling and maximum variation sampling. The interviews were analysed using the Colaizzi's 7-step method. RESULTS: 'Breakdown and healing' is a strong thread in postpartum nurses' work adaptation. It links 13 subthemes in the interview data, which can be grouped under three overarching themes: (a) changes and challenges of multiple roles; (b) self-coping and social support; and (c) further needs after returning to work. The phrase 'breakdown and healing' reflects the mutual relationship between stress and coping among postpartum nurses. The changes and challenges associated with being required to fulfil multiple roles of mothers, wives and nurses make the subjects feel on the verge of 'breakdown'. When returning to work, most of them move slowly towards 'healing' through positive self-management and support from their partners, families, supervisors and colleagues. Moreover, their ongoing demands and unsolved problems - such as their desire for a workplace that is friendly and serves their needs - were generated by the constant process of 'breakdown and healing'. CONCLUSIONS: Understanding how postpartum nurses returning to work perceive adaptation experiences is essential for nursing managers, who can use the findings to implement targeted measures to shorten postpartum nurses' maladaptation period after returning to work and promote their work adaptation. This study underscores the critical importance of personalized return-to-work training, flexible work arrangements, support from colleagues and managers, well-established maternal facilities and services, and targeted policy efforts in enhancing postpartum nurses' work adaptation.

10.
BMC Nurs ; 23(1): 462, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977977

RESUMO

OBJECTIVE: Relational job characteristics include perceived social worth and perceived social influence. Good relational job characteristics mean that nurses have high prosocial behavior. The purpose of this study was to explore the potential profile of nurses' relational job characteristics, influencing factors and their differences in turnover intention and subjective well-being, thus finding the most suitable clinical relationship job characteristics. METHODS: A cross-sectional survey was conducted among 1013 clinical nurses using the general demographic data questionnaire, Relational Job Characteristics scale, Turnover Intention Questionnaire and Campbell index of well-being. A latent profile analysis was performed to explore relational job characteristics latent profiles. Multinomial logistic regression analysis was conducted to examine the predictors of profile membership, and a one-way analysis of variance was applied to compare the turnover intention and subjective well-being in each latent profile. RESULTS: Five latent profiles were identified and labeled 'High prosocial job characteristics' profile (20.7%), 'Moderate prosocial job characteristics' profile (41.7%), 'High social worth-low social impact perceived' profile (6.3%), 'Low social worth-high social impact perceived' profile (18.8%) and 'Low prosocial job characteristics' profile (12.5%). Factors affecting the different types of nurse relationship job characteristics include age, marital status, hospital department, nursing years, professional title and hospital position. Among them, chief nurse, nurses with more than 20 years of nursing experience and obstetrics and gynecology nurses were more likely to be 'high prosocial job characteristics' profile. The turnover intention of nurses in 'high prosocial job characteristics' profile was significantly lower than that of other profiles, and their subjective well-being was significantly higher than that of other profiles. CONCLUSION: Improving nurses' perception of social worth and social impact on clinical work can improve nurses' prosocial behavior and subjective well-being, and reduce their turnover intention. Nursing managers or policy makers can formulate targeted intervention measures according to the influencing factors of potential profiles.

11.
Nurs Ethics ; 31(4): 635-651, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38148631

RESUMO

BACKGROUND: Compassion fatigue is often associated with moral distress in the nursing practice among registered nurses. Moral resilience is an important ability to maintain, restore, or promote their physical and mental health in response to ethical dilemmas in nursing. Moral resilience can be utilized as a potential solution to aid registered nurses in effectively managing compassion fatigue. AIM: To identify latent profiles of moral resilience among registered nurses and to explore the relationships of these profiles with compassion fatigue. RESEARCH DESIGN: From August 2022 to December 2022, 569 nurses were recruited in two general hospitals, in China. A Rushton Moral Resilience Scale and the Chinese version of Compassion Fatigue-Short Scale were given to the participants. A latent profile analysis was conducted to explore moral resilience latent profiles. Predictors of profiles membership was evaluated using multinomial logistic regression analysis, and the compassion fatigue scores of each latent profile were compared using a one-way analysis of variance. ETHICAL CONSIDERATIONS: We obtained ethical approval from the Institution Review Board of Xiangya School of Nursing, Central South University (IRB No. E202293, approved 15/July/2022). RESULTS: A four-profile moral resilience model best fit the data. Different levels and shapes differentiated the four profiles: high moral resilience (28.7%), moderate moral resilience (52.3%), low responses and high efficacy (16.2%), and low moral resilience (2.8%). Nurses with bachelor's degrees were more likely to belong to the high moral resilience (OR = 0.118, p = .038) and moderate moral resilience (OR = 0.248, p = .045); Nurses who were divorced or separated (OR = 11.746, p = .025) and very dissatisfied with their work (OR = 0.001, p = .049) were more probably belonging to low moral resilience. Nurses who had received ethical training in the hospital were more likely involved in high moral resilience (OR = 5.129, p = .003) and low responses and high efficacy (OR = 5.129, p = .003). In each profile of moral resilience, compassion fatigue was experienced differently by the participants (F = 13.05, p < .001). CONCLUSIONS: Developing and implementing interventions tailored to each nurse's moral resilience profile would maximize interventions' effectiveness and reduce nurses' compassion fatigue.


Assuntos
Fadiga de Compaixão , Enfermeiras e Enfermeiros , Resiliência Psicológica , Humanos , Feminino , Fadiga de Compaixão/psicologia , Adulto , Masculino , China , Inquéritos e Questionários , Enfermeiras e Enfermeiros/psicologia , Enfermeiras e Enfermeiros/estatística & dados numéricos , Pessoa de Meia-Idade , Psicometria/instrumentação , Psicometria/métodos , Princípios Morais
12.
J Am Chem Soc ; 145(46): 25332-25340, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37944150

RESUMO

Rational control and understanding of isomerism are of significance but still remain a great challenge in reticular frameworks, in particular, for covalent organic frameworks (COFs) due to the complicated synthesis and energy factors. Herein, reaction of 3,3',5,5'-tetra(4-formylphenyl)-2,2',6,6'-tetramethoxy-1,1'-biphenyl (TFTB) with 3,3',5,5'-tetrakis(4-aminophenyl)bimesityl (TAPB) under different reaction conditions affords single crystals of two 3D COF isomers, namely, USTB-20-dia and USTB-20-qtz. Their structures with resolutions up to 0.9-1.1 Å have been directly solved by three-dimensional electron diffraction (3D ED) and synchrotron single crystal X-ray diffraction, respectively. USTB-20-dia and USTB-20-qtz show rare 2 × 2-fold interpenetrated dia-b nets and 3-fold interpenetrated qtz-b frameworks. Comparative studies of the crystal structures of these COFs and theoretical simulation results indicate the crucial role of the flexible molecular configurations of building blocks in the present interpenetrated topology isomerism. This work not only presents the rare COF isomers but also gains an understanding of the formation of framework isomerism from both single crystal structures and theoretical simulation perspectives.

13.
Small ; 19(12): e2205936, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36634970

RESUMO

It remains a great challenge to design and manufacture battery-type supercapacitors with satisfactory flexibility, appropriate mechanical property, and high energy density under high power density. Herein, a concept of porous engineering is proposed to simply prepare two-layered bimetallic heterojunction with porous structures. This concept is successfully applied in fabrication of flexible electrode based on CuO-Co(OH)2 lamella on Cu-plated carbon cloth (named as CPCC@CuO@Co(OH)2 ). The unique structure brings the electrode a high specific capacity of 3620 mF cm-2 at 2 mA cm-2 and appropriate mechanical properties with Young's modulus of 302.0 MPa. Density functional theory calculations show that porous heterojunction provides a higher intensity of electron state density near the Fermi level (E-Ef  = 0 eV), leading to a highly conductive CPCC@CuO@Co(OH)2 electrode with both efficient charge transport and rapid ion diffusion. Notably, the supercapacitor assembled from CPCC@CuO@Co(OH)2 //CC@AC shows high energy density of 127.7 W h kg-1 at 750.0 W kg-1 , remarkable cycling performance (95.53% capacity maintaining after 10 000 cycles), and desired mechanical flexibility. The methodology and results in this work will accelerate the transformative developments of flexible energy storage devices in practical applications.

14.
Small ; 19(31): e2206597, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36617512

RESUMO

Electrolyte additive is an effective strategy to inhibit the uncontrolled growth of Li dendrites for lithium metal batteries (LMBs). However, most of the additives are complex synthesis and prone to decompose in cycling. Herein, in order to guide the homogeneous deposition of Li+ , carbonized polymer dots (CPDs) as electrolyte additives are successfully designed and synthesized by microwave (M-CPDs) and hydrothermal (H-CPDs) approaches. The controllable functional groups containing N or O (especially pyridinic-N, pyrrolic-N, and carboxyl group) enable CPDs to keep stable in electrolytes for at least 3 months. Meanwhile, the clusters formed between CPDs and Li+ through electrostatic interaction effectively guide the uniform Li dispersion and limit the "tip effect" and dendrite formation. Moreover, as lithiophilic groups increase, the strong electrostatic interference for the solvation effect of Li+ in the electrolyte is formed, which induces faster Li+ diffusion/transfer. As expected, H-CPDs achieve the ultra-even Li+ transfer. The corresponding Li//LiFePO4 full cell delivers a high capacity retention rate of 93.8% after 200 cycles, which is much higher than that of the cells without additives (61.2%) and with M-CPDs (83.7%) as additives. The strategy in this work provides a theoretical direction for CPDs as electrolyte additives used in energy storage devices.

15.
Small ; 19(47): e2304751, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37485645

RESUMO

The dendrite growth and parasitic reactions that occur on Zn metal anode (ZMA)/electrolyte interface hinder the development of aqueous zinc ion batteries (AZIBs) in next-generation renewable energy storage systems. Fortunately, reconstructing the inner Helmholtz layer (IHL) by introducing an electrolyte additive, is viewed as one of the most promising strategies to harvest the stable ZMA. Herein, (4-chloro-3-nitrophenyl) (pyridin-4-yl) methanone (CNPM) with quadruple functional groups is introduced into the ZnSO4 electrolyte to reshape the interface between ZMA and electrolyte and change the solvation structure of Zn2+ . Density functional theory (DFT) calculations manifest that the ─C═O, ─Cl, ─C═N─, and ─NO2 functional groups of CNPM interact with metallic Zn simultaneously and adsorb on the ZMA surface in a parallel arrangement manner, thus forming a water-poor IHL and creating well-arranged ion transportation channels. Furthermore, theoretical calculations and experimental results demonstrate that CNPM absorbed on the Zn anode surface can serve as zincophilic sites for inducing uniform Zn deposition along the (002) plane. Benefiting from the synergistic effect of these functions, the dendrite growth and parasitic reactions are suppressed significantly. As a result, ZMA exhibits a long cycle life (2900 h) and high coulombic efficiency (CE) (500 cycles) in the ZnSO4 +CNPM electrolyte.

16.
Small ; 19(52): e2304459, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37649202

RESUMO

Despite being one of the most promising materials in anode materials, molybdenum sulfide (MoS2 ) encounters certain obstacles, such as inadequate cycle stability, low conductivity, and unsatisfactory charge-discharge (CD) rate performance. In this study, a novel approach is employed to address the drawbacks of MoS2 . Carbon polymer dots (CPDs) are incorporated to prepare three-dimensional (3D) nanoflower-like spheres of MoS2 @CPDs through the self-assembly of MoS2 2D nanosheets, followed by annealing at 700 °C. The CPDs play a main role in the creation of the nanoflower-like spheres and also mitigate the MoS2 nanosheet limitations. The nanoflower-like spheres minimize volume changes during cycling and improve the rate performance, leading to exceptional rate performance and cycling stability in both Lithium-ion and Sodium-ion batteries (LIBs and SIBs). The optimized MoS2 @CPDs-2 electrode achieves a superb capacity of 583.4 mA h g-1 at high current density (5 A g-1 ) after 1000 cycles in LIBs, and the capacity remaining of 302.8 mA h g-1 after 500 cycles at 5 A g-1 in SIBs. Additionally, the full cell of LIBs/SIBs exhibits high capacity and good cycling stability, demonstrating its potential for practical application in fast-charging and high-energy storage.

17.
J Org Chem ; 88(23): 16132-16143, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38037695

RESUMO

Comprehensive computational studies were carried out to explore the mechanisms and origin of regioselectivity in the Pd-catalyzed regiodivergent coupling reaction of indazoles and isoprene. Three different insertion models were investigated for regioselectivity 1,2- or 4,3-insertion with respect to the electrophilic sites on isoprene under two different ligands (L1 and L2) and acids ((PhO)2PO2H, (nBuO)2PO2H) via PdII-H species, allyl-π-PdII-O, and indazoles-acid-assisted PdII-π-allyl. The calculated results show that the PdII-π-allyl coordinated mechanism is the most preferred one. The noncovalent interactions between the less bulky ligand L1, substrates, and (PhO)2PO2- are found to be key factors for 1,2-insertion. The 4,3-insertion selectivity is primarily controlled by the steric repulsion of the t-Bu group of bulky ligand L2 and substrate, as well as the geometry distortion. Therefore, the regioselectivity difference of the 1,2- and 4,3-insertion on electrophilic sites is controlled by the synergistic effect of ligands and acids instead of the size of the ligand. Similarly, nucleophilic site selectivity at N1 or N2 of indazoles is governed by cooperative acid BF3 and solvent iPrOH rather than BF3 alone. Overall, our findings might open a new avenue for designing more efficient regioselective 1,2- or 4,3-addition or N1-/N2-selective nucleophilic reactions.

18.
Nanotechnology ; 34(40)2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37369182

RESUMO

Although significant achievements in improving the stability of MoS2anodes have been made, the cycling life in most studies is still less than 1000 cycles. This is because MoS2anodes directly contact the electrolyte and generate byproducts, leading to the loss of active mass and capacity decay. Herein, the inner-outer dual space protection of MoS2fibers is realized by regulating the surface and interface structure of electrospinning precursors (noted as X-MoS2/CNFs). Inside the fibers, Mo-N covalent bond is constructed to anchor the active material, preventing MoS2from falling off the matrix after multiple cycles. Simultaneously, surface of the fibers, a stable solid electrolyte interface layer is induced to prevent contact between active materials and electrolytes. In addition, the initial Coulombic efficiency is enhanced as high as 84.4%. The profound investigations of morphological evolution and internal real-time resistance confirm the double structural protection of 800-MoS2/CNFs. As a result, a decent cycling performance (408.9 mAh g-1at 1000 mA g-1for 2000 cycles) and the satisfied rate capacities (100-1000 mA g-1) are achieved. This work provides a new idea for the preparation of stable anodes for alkali metal ion secondary batteries.

19.
Phys Chem Chem Phys ; 25(36): 24468-24474, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37655746

RESUMO

Two-dimensional (2D) materials used as anodes in metal-ion batteries have attracted increased attention due to their high specific surface area, abundant active sites and good electronic properties. Searching for 2D materials with high storage capacities and low diffusion energy barriers is one of the most effective ways to design novel anode materials. In this work, based on first-principles calculations, we design a new 2D B3S2 monolayer with high thermodynamic and dynamic stability. The obtained B3S2 monolayer has a high cohesive energy, ensuring the feasibility of experimental synthesis. These characteristics of the B3S2 monolayer prompt us to explore its application as an anode material. The B3S2 monolayer exhibits not only a metallic nature but also a low diffusion energy barrier (0.037 eV) and open-circuit voltage (0.09 V). More importantly, the B3S2 monolayer shows a very high theoretical capacity of 1658 mA h g-1 as an anode material for sodium-ion batteries, which is comparable to other similar or common 2D materials. All of these intriguing properties make the B3S2 monolayer a promising 2D anode material for sodium-ion batteries.

20.
BMC Nurs ; 22(1): 122, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37059992

RESUMO

BACKGROUND: Promoting self-directed learning (SDL) among nursing undergraduates is crucial to meet the new requirements of the healthcare system and to adapt to online learning contexts during the COVID-19 pandemic. Therefore, identifying the classification features of SDL ability and developing targeted interventions are both critical. Professional identity (PI) may contribute to the cultivation of SDL ability, but their relationship remains relatively unknown. This study aimed to explore the subgroups of SDL ability and their differences in PI among nursing undergraduates during the COVID-19 pandemic. METHODS: A total of 2438 nursing undergraduates at four universities in China were enrolled in this cross-sectional study from November 2021 to February 2022. The Self-Directed Learning Scale of Nursing Undergraduates (SLSNU) and the Professional Identity Scale for Nursing Students (PISNS) were administered. A latent profile analysis was performed to explore SDL ability latent profiles. Multinomial logistic regression analysis was conducted to examine the predictors of profile membership, and a one-way analysis of variance was applied to compare the PI scores in each latent profile. RESULTS: Three latent profiles were identified and labeled 'low SDL ability' (n = 749, 30.7%), 'low initiative of help-seeking' (n = 1325, 54.4%) and 'high SDL ability' (n = 364, 14.9%). Multinomial logistic regression analysis suggested that nursing undergraduates who voluntarily chose a nursing major, had served as a student cadre, and had participated in clinical practicum were less likely to be included in the "low SDL ability" group. The average PI score was statistically different across the three profiles (F = 884.40, p < 0.001). CONCLUSION: The SDL ability among nursing undergraduates was divided into three profiles, and results show that promoting PI may effectively foster SDL ability. This study highlights the importance of targeted interventions by considering their distinct SDL ability patterns, especially during the COVID-19 pandemic.

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