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1.
Nat Commun ; 15(1): 3325, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38637537

RESUMEN

The effective flow of electrons through bulk electrodes is crucial for achieving high-performance batteries, although the poor conductivity of homocyclic sulfur molecules results in high barriers against the passage of electrons through electrode structures. This phenomenon causes incomplete reactions and the formation of metastable products. To enhance the performance of the electrode, it is important to place substitutable electrification units to accelerate the cleavage of sulfur molecules and increase the selectivity of stable products during charging and discharging. Herein, we develop a single-atom-charging strategy to address the electron transport issues in bulk sulfur electrodes. The establishment of the synergistic interaction between the adsorption model and electronic transfer helps us achieve a high level of selectivity towards the desirable short-chain sodium polysulfides during the practical battery test. These finding indicates that the atomic manganese sites have an enhanced ability to capture and donate electrons. Additionally, the charge transfer process facilitates the rearrangement of sodium ions, thereby accelerating the kinetics of the sodium ions through the electrostatic force. These combined effects improve pathway selectivity and conversion to stable products during the redox process, leading to superior electrochemical performance for room temperature sodium-sulfur batteries.

2.
Adv Mater ; : e2400810, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38569213

RESUMEN

The catalytic activation of the Li-S reaction is fundamental to maximize the capacity and stability of Li-S batteries (LSBs). Current research on Li-S catalysts mainly focuses on optimizing the energy levels to promote adsorption and catalytic conversion, while frequently overlooking the electronic spin state influence on charge transfer and orbital interactions. Here, hollow NiS2/NiSe2 heterostructures encapsulated in a nitrogen-doped carbon matrix (NiS2/NiSe2@NC) are synthesized and used as a catalytic additive in sulfur cathodes. The NiS2/NiSe2 heterostructure promotes the spin splitting of the 3d orbital, driving the Ni3+ transformation from low to high spin. This high spin configuration raises the electronic energy level and activates the electronic state. This accelerates the charge transfer and optimizes the adsorption energy, lowering the reaction energy barrier of the polysulfides conversion. Benefiting from these characteristics, LSBs based on NiS2/NiSe2@NC/S cathodes exhibit high initial capacity (1458 mAh·g⁻1 at 0.1C), excellent rate capability (572 mAh·g⁻1 at 5C), and stable cycling with an average capacity decay rate of only 0.025% per cycle at 1C during 500 cycles. Even at high sulfur loadings (6.2 mg·cm⁻2), high initial capacities of 1173 mAh·g⁻1 (7.27 mAh·cm⁻2) are measured at 0.1C, and 1058 mAh·g⁻1 is retained after 300 cycles.

3.
Curr Issues Mol Biol ; 46(3): 2155-2165, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38534755

RESUMEN

An increased neutrophil-to-lymphocyte ratio (NLR) is a poor prognostic biomarker in various types of cancer, because it reflects the inhibition of lymphocytes in the circulation and tumors. In urologic cancers, upper tract urothelial carcinoma (UTUC) is known for its aggressive features and lack of T cell infiltration; however, the association between neutrophils and suppressed T lymphocytes in UTUC is largely unknown. In this study, we examined the relationship between UTUC-derived factors and tumor-associated neutrophils or T lymphocytes. The culture supernatant from UTUC tumor tissue modulated neutrophils to inhibit T cell proliferation. Among the dominant factors secreted by UTUC tumor tissue, apolipoprotein A1 (Apo-A1) exhibited a positive correlation with NLR. Moreover, tumor-infiltrating neutrophils were inversely correlated with tumor-infiltrating T cells. Elevated Apo-A1 levels in UTUC were also inversely associated with the population of tumor-infiltrating T cells. Our findings indicate that elevated Apo-A1 expression in UTUC correlates with tumor-associated neutrophils and T cells. This suggests a potential immunomodulatory effect on neutrophils and T cells within the tumor microenvironment, which may represent therapeutic targets for UTUC treatment.

4.
Chem Soc Rev ; 53(8): 3829-3895, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38436202

RESUMEN

Subnanometer pores/channels (SNPCs) play crucial roles in regulating electrochemical redox reactions for rechargeable batteries. The delicately designed and tailored porous structure of SNPCs not only provides ample space for ion storage but also facilitates efficient ion diffusion within the electrodes in batteries, which can greatly improve the electrochemical performance. However, due to current technological limitations, it is challenging to synthesize and control the quality, storage, and transport of nanopores at the subnanometer scale, as well as to understand the relationship between SNPCs and performances. In this review, we systematically classify and summarize materials with SNPCs from a structural perspective, dividing them into one-dimensional (1D) SNPCs, two-dimensional (2D) SNPCs, and three-dimensional (3D) SNPCs. We also unveil the unique physicochemical properties of SNPCs and analyse electrochemical couplings in SNPCs for rechargeable batteries, including cathodes, anodes, electrolytes, and functional materials. Finally, we discuss the challenges that SNPCs may face in electrochemical reactions in batteries and propose future research directions.

5.
Adv Mater ; : e2402337, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38458611

RESUMEN

Room-temperature sodium-sulfur (RT-Na/S) batteries are promising alternatives for next-generation energy storage systems with high energy density and high power density. However, some notorious issues are hampering the practical application of RT-Na/S batteries. Besides, the working mechanism of RT-Na/S batteries under practical conditions such as high sulfur loading, lean electrolyte, and low capacity ratio between the negative and positive electrode (N/P ratio), is of essential importance for practical applications, yet the significance of these parameters has long been disregarded. Herein, it is comprehensively reviewed recent advances on Na metal anode, S cathode, electrolyte, and separator engineering for RT-Na/S batteries. The discrepancies between laboratory research and practical conditions are elaborately discussed, endeavors toward practical applications are highlighted, and suggestions for the practical values of the crucial parameters are rationally proposed. Furthermore, an empirical equation to estimate the actual energy density of RT-Na/S pouch cells under practical conditions is rationally proposed for the first time, making it possible to evaluate the gravimetric energy density of the cells under practical conditions. This review aims to reemphasize the vital importance of the crucial parameters for RT-Na/S batteries to bridge the gaps between laboratory research and practical applications.

6.
Adv Sci (Weinh) ; : e2310115, 2024 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-38491872

RESUMEN

In this work, 2D ferromagnetic M3 GeTe2 (MGT, M = Ni/Fe) nanosheets with rich atomic Te vacancies (2D-MGTv ) are demonstrated as efficient OER electrocatalyst via a general mechanical exfoliation strategy. X-ray absorption spectra (XAS) and scanning transmission electron microscope (STEM) results validate the dominant presence of metal-O moieties and rich Te vacancies, respectively. The formed Te vacancies are active for the adsorption of OH* and O* species while the metal-O moieties promote the O* and OOH* adsorption, contributing synergistically to the faster oxygen evolution kinetics. Consequently, 2D-Ni3 GeTe2v exhibits superior OER activity with only 370 mV overpotential to reach the current density of 100 mA cm-2 and turnover frequency (TOF) value of 101.6 s-1 at the overpotential of 200 mV in alkaline media. Furthermore, a 2D-Ni3 GeTe2v -based anion-exchange membrane (AEM) water electrolysis cell (1 cm2 ) delivers a current density of 1.02 and 1.32 A cm-2 at the voltage of 3 V feeding with 0.1 and 1 m KOH solution, respectively. The demonstrated metal-O coordination with abundant atomic vacancies for ferromagnetic M3 GeTe2 and the easily extended preparation strategy would enlighten the rational design and fabrication of other ferromagnetic materials for wider electrocatalytic applications.

8.
Adv Mater ; : e2312207, 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38329004

RESUMEN

Linearly interlinked single atoms offer unprecedented physiochemical properties, but their synthesis for practical applications still poses significant challenges. Herein, linearly interlinked iron single-atom catalysts that are loaded onto interconnected carbon channels as cathodic sulfur hosts for room-temperature sodium-sulfur batteries are presented. The interlinked iron single-atom exhibits unique metallic iron bonds that facilitate the transfer of electrons to the sulfur cathode, thereby accelerating the reaction kinetics. Additionally, the columnated and interlinked carbon channels ensure rapid Na+ diffusion kinetics to support high-rate battery reactions. By combining the iron atomic chains and the topological carbon channels, the resulting sulfur cathodes demonstrate effective high-rate conversion performance while maintaining excellent stability. Remarkably, even after 5000 cycles at a current density of 10 A g-1 , the Na-S battery retains a capacity of 325 mAh g-1 . This work can open a new avenue in the design of catalysts and carbon ionic channels, paving the way to achieve sustainable and high-performance energy devices.

9.
Nanomicro Lett ; 16(1): 78, 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38190094

RESUMEN

The concentration difference in the near-surface region of lithium metal is the main cause of lithium dendrite growth. Resolving this issue will be key to achieving high-performance lithium metal batteries (LMBs). Herein, we construct a lithium nitrate (LiNO3)-implanted electroactive ß phase polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) crystalline polymorph layer (PHL). The electronegatively charged polymer chains attain lithium ions on the surface to form lithium-ion charged channels. These channels act as reservoirs to sustainably release Li ions to recompense the ionic flux of electrolytes, decreasing the growth of lithium dendrites. The stretched molecular channels can also accelerate the transport of Li ions. The combined effects enable a high Coulombic efficiency of 97.0% for 250 cycles in lithium (Li)||copper (Cu) cell and a stable symmetric plating/stripping behavior over 2000 h at 3 mA cm-2 with ultrahigh Li utilization of 50%. Furthermore, the full cell coupled with PHL-Cu@Li anode and LiFePO4 cathode exhibits long-term cycle stability with high-capacity retention of 95.9% after 900 cycles. Impressively, the full cell paired with LiNi0.87Co0.1Mn0.03O2 maintains a discharge capacity of 170.0 mAh g-1 with a capacity retention of 84.3% after 100 cycles even under harsh condition of ultralow N/P ratio of 0.83. This facile strategy will widen the potential application of LiNO3 in ester-based electrolyte for practical high-voltage LMBs.

10.
Sci Rep ; 14(1): 1997, 2024 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-38263244

RESUMEN

Gastrointestinal (GI) cancers account for a significant incidence and mortality rates of cancers globally. Utilization of a phenomic data approach allows researchers to reveal the mechanisms and molecular pathogenesis of these conditions. We aimed to investigate the association between the phenomic features and GI cancers in a large cohort study. We included 502,369 subjects aged 37-73 years in the UK Biobank recruited since 2006, followed until the date of the first cancer diagnosis, date of death, or the end of follow-up on December 31st, 2016, whichever occurred first. Socio-demographic factors, blood chemistry, anthropometric measurements and lifestyle factors of participants collected at baseline assessment were analysed. Unvariable and multivariable logistic regression were conducted to determine the significant risk factors for the outcomes of interest, based on the odds ratio (OR) and 95% confidence intervals (CI). The analysis included a total of 441,141 participants, of which 7952 (1.8%) were incident GI cancer cases and 433,189 were healthy controls. A marker, cystatin C was associated with total and each gastrointestinal cancer (adjusted OR 2.43; 95% CI 2.23-2.64). In this cohort, compared to Asians, the Whites appeared to have a higher risk of developing gastrointestinal cancers. Several other factors were associated with distinct GI cancers. Cystatin C and race appear to be important features in GI cancers, suggesting some overlap in the molecular pathogenesis of GI cancers. Given the small proportion of Asians within the UK Biobank, the association between race and GI cancers requires further confirmation.


Asunto(s)
Cistatina C , Neoplasias , Humanos , Biobanco del Reino Unido , Bancos de Muestras Biológicas , Estudios de Cohortes , Fenómica
11.
Int J Environ Health Res ; : 1-14, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38287203

RESUMEN

This study evaluated the acceptability and tolerability of three alcohol-based hand rubs (ABHRs) at Sarawak General Hospital, Malaysia. Conducted from 12-26 November 2021 using a modified WHO Protocol, it involved a survey among health workers and concessionaires, with a 35% response rate (1,598 of 4,628 participants). The majority were nurses (60.8%), with the medical division most represented (28.4%). Most respondents (93.2%) used ABHRs at least five days a week and found them easily accessible (72.3%). Product B was the preferred ABHR (65%), primarily for its color and fragrance, surpassing WHO's 50% approval rate in these aspects. However, no other product features met WHO criteria. There were no significant differences in self-reported skin tolerability across the products, and none achieved overall WHO approval. These results offer important insights for ABHR selection in developing countries and highlight the value of the WHO Protocol in assessing product acceptability and tolerability.

12.
Angew Chem Int Ed Engl ; 63(3): e202313142, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-37917045

RESUMEN

Sodium dual-ion batteries (Na-DIBs) have attracted increasing attention due to their high operative voltages and low-cost raw materials. However, the practical applications of Na-DIBs are still hindered by the issues, such as low capacity and poor Coulombic efficiency, which is highly correlated with the compatibility between electrode and electrolyte but rarely investigated. Herein, fluoroethylene carbonate (FEC) is introduced into the electrolyte to regulate cation/anion solvation structure and the stability of cathode/anode-electrolyte interphase of Na-DIBs. The FEC modulates the environment of PF6 - solvation sheath and facilitates the interaction of PF6 - on graphite. In addition, the NaF-rich interphase caused by the preferential decomposition of FEC effectively inhibits side reactions and pulverization of anodes with the electrolyte. Consequently, Sb||graphite full cells in FEC-containing electrolyte achieve an improved capacity, cycling stability and Coulombic efficiency. This work elucidates the underlying mechanism of bifunctional FEC and provides an alternative strategy of building high-performance dual ion batteries.

13.
Heliyon ; 9(12): e22668, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38149205

RESUMEN

Quality of life (QOL) should ideally be determined by a broader spectrum of measurable parameters. This study aims to develop and validate a study instrument that is designed to determine a holistic measure of health and non-health aspects of QOL, and it is called the 'Significant Quality of Life Measure' (SigQOLM). This study involves five phases which aim to (i) explore and understand the subject matter content, (ii) develop a questionnaire, (iii) assess its content validity and face validity, (iv) conduct a pilot study, and lastly (v) perform a field-test by using the questionnaire. For the field-testing phase, a cross-sectional study was conducted which elicited responses from healthcare workers via a self-administered survey for all the SigQOLM items. Based on the results, the overall framework of the SigQOLM consists of four elements, 18 domains with 69 items. The element of "Health" is measured by nine domains, while "Relationships", "Functional activities, and "Survival" are measured by three domains respectively. The SigQOLM has been developed successfully and then validated with a high level of reliability, validity, and overall model fit. Therefore, the SigQOLM will provide researchers and policymakers another viable option to elicit a more comprehensive outcome measure of QOL which shall then enable them to implement specific interventions for improving the QOL of all the people, both healthy or otherwise.

14.
Artículo en Inglés | MEDLINE | ID: mdl-37943536

RESUMEN

AIM: Participant recruitment has always been a major challenge in clinical trials. This study aimed to develop and validate the Join Clinical Trial Questionnaire (JoinCT), exploring the willingness to join a clinical trial and associated factors in patients. METHODS: This questionnaire development study involved four phases: (i) exploring and understanding the subject matter, (ii) questionnaire development, (iii) content validity testing, and lastly, (iv) field-testing of the questionnaire. For the field-testing phase, a cross-sectional self-administered survey of JoinCT was conducted among cancer patients with various socio-demographic backgrounds and medical conditions. Besides content validity, Cronbach's alpha was used to evaluate the internal consistency of domains, and confirmatory factor analysis was used to evaluate the model fit of the JoinCT framework. RESULTS: A total of 389 respondents participated in the survey. Based on the results obtained from a field data collection phase, JoinCT consisted of four independent variables domains, namely "knowledge", "perception of benefits", "perception of risks", and "confidence". The only dependent variable was the willingness to participate in a clinical trial. The minimum Cronbach's alpha was 0.937, and the model fit for the overall framework of JoinCT is also excellent with Comparative Fit Index (> 0.90), root mean square error approximation (< 0.08), and Standardized Root Mean Square Residual (< 0.08). CONCLUSIONS: The Join Clinical Trial Questionnaire (JoinCT) was successfully validated with excellent reliability and validity, and a good model fit. The main factors that contribute to willingness to participate in clinical trials are knowledge, perception of benefits, perception of risks, and confidence.

15.
Natl Sci Rev ; 10(11): nwad223, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37818110

RESUMEN

This perspective emphasizes the need for global cooperation and decisive action to address the urgent threat of climate change and achieve the net zero emissions goal before 2050.

16.
Adv Mater ; 35(40): e2302613, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37390487

RESUMEN

Hard carbon anodes with all-plateau capacities below 0.1 V are prerequisites to achieve high-energy-density sodium-ion storage, which holds promise for future sustainable energy technologies. However, challenges in removing defects and improving the insertion of sodium ions head off the development of hard carbon to achieve this goal. Herein, a highly cross-linked topological graphitized carbon using biomass corn cobs through a two-step rapid thermal-annealing strategy is reported. The topological graphitized carbon constructed with long-range graphene nanoribbons and cavities/tunnels provides a multidirectional insertion of sodium ions whilst eliminating defects to absorb sodium ions at the high voltage region. Evidence from advanced techniques including in situ XRD, in situ Raman, and in situ/ex situ transmission electron microscopy (TEM) indicates that the sodium ions' insertion and Na cluster formation occurred between curved topological graphite layers and in the topological cavity of adjacent graphite band entanglements. The reported topological insertion mechanism enables outstanding battery performance with a single full low-voltage plateau capacity of 290 mAh g-1 , which is almost 97% of the total capacity.

17.
Angew Chem Int Ed Engl ; 62(33): e202307123, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37353890

RESUMEN

The conventional industrial production of nitrogen-containing fertilizers, such as urea and ammonia, relies heavily on energy-intensive processes, accounting for approximately 3 % of global annual CO2 emissions. Herein, we report a sustainable electrocatalytic approach that realizes direct and selective synthesis of urea and ammonia from co-reduction of CO2 and nitrates under ambient conditions. With the assistance of a copper (Cu)-based salphen organic catalyst, outstanding urea (3.64 mg h-1 mgcat -1 ) and ammonia (9.73 mg h-1 mgcat -1 ) yield rates are achieved, in addition to a remarkable Faradaic efficiency of 57.9±3 % for the former. This work proposes an appealing sustainable route to converting greenhouse gas and waste nitrates by renewable energies into value-added fertilizers.

18.
J Clin Med ; 12(8)2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-37109153

RESUMEN

Health-related quality of life (HRQOL) is one of the most important outcome measures to be assessed by medical research. This study aims to develop and validate an instrument called the "health-related quality of life with six domains" (HRQ-6D), which aims to measure an individual's health-related quality of life within a 24 h period of time. This is a questionnaire development study involving five phases, which are (i) to explore the subject matter content for gaining a better understanding of the topic, (ii) to develop the questionnaire, (iii) to assess both its content validity and face validity, (iv) to conduct a pilot study, and finally, (v) to undertake a field testing of the questionnaire. For the field-testing phase, a cross-sectional study involving a self-administered survey for HRQ-6D items was conducted among healthcare workers with various health conditions. Exploratory factor analysis was initially applied to construct the major dimensions of the HRQ-6D. Confirmatory factor analysis was subsequently applied to evaluate the model fit of the overall framework of the HRQ-6D. The clinical utility of this HRQ-6D was also assessed via its association with actual clinical evidence. A total of 406 respondents participated in the survey. Six domains were identified from the analysis, namely "pain", "physical strength", "emotion", "self-care", "mobility", and "perception of future health" comprising two items in each domain. Each domain was reported to have a minimum value of Cronbach's alpha of 0.731, and the model fit for the overall framework of the HRQ-6D was also found to be excellent. Exploratory factor analysis was undertaken for the 12 items of the HRQ-6D. All the domains can be categorized into three major dimensions, namely "health", "body function", and "future perception", with a minimum value for their factor loadings of at least 0.507. A notable finding was that the HRQ-6D was significantly associated with an individual's existing comorbidities and current status of health (p < 0.05). This study successfully validated the HRQ-6D, and we found it to possess both excellent levels of reliability and validity and a satisfactory degree of model fit; it was also significantly associated with actual clinical evidence.

19.
Angew Chem Int Ed Engl ; 62(17): e202301833, 2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-36853880

RESUMEN

The oxygen reduction reaction (ORR) on transition single-atom catalysts (SACs) is sustainable in energy-conversion devices. However, the atomically controllable fabrication of single-atom sites and the sluggish kinetics of ORR have remained challenging. Here, we accelerate the kinetics of acid ORR through a direct O-O cleavage pathway through using a bi-functional ligand-assisted strategy to pre-control the distance of hetero-metal atoms. Concretely, the as-synthesized Fe-Zn diatomic pairs on carbon substrates exhibited an outstanding ORR performance with the ultrahigh half-wave potential of 0.86 V vs. RHE in acid electrolyte. Experimental evidence and density functional theory calculations confirmed that the Fe-Zn diatomic pairs with a specific distance range of around 3 Å, which is the key to their ultrahigh activity, average the interaction between hetero-diatomic active sites and oxygen molecules. This work offers new insight into atomically controllable SACs synthesis and addresses the limitations of the ORR dissociative mechanism.

20.
Adv Mater ; 35(1): e2206828, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36308045

RESUMEN

Room-temperature sodium-sulfur (RT-Na/S) batteries possess high potential for grid-scale stationary energy storage due to their low cost and high energy density. However, the issues arising from the low S mass loading and poor cycling stability caused by the shuttle effect of polysulfides seriously limit their operating capacity and cycling capability. Herein, sulfur-doped graphene frameworks supporting atomically dispersed 2H-MoS2 and Mo1 (S@MoS2 -Mo1 /SGF) with a record high sulfur mass loading of 80.9 wt.% are synthesized as an integrated dual active sites cathode for RT-Na/S batteries. Impressively, the as-prepared S@MoS2 -Mo1 /SGF display unprecedented cyclic stability with a high initial capacity of 1017 mAh g-1 at 0.1 A g-1 and a low-capacity fading rate of 0.05% per cycle over 1000 cycles. Experimental and computational results including X-ray absorption spectroscopy, in situ synchrotron X-ray diffraction and density-functional theory calculations reveal that atomic-level Mo in this integrated dual-active-site forms a delocalized electron system, which could improve the reactivity of sulfur and reaction reversibility of S and Na, greatly alleviating the shuttle effect. The findings not only provide an effective strategy to fabricate high-performance dual-site cathodes, but also deepen the understanding of their enhancement mechanisms at an atomic level.

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