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1.
Inorg Chem ; 63(28): 13100-13109, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38953738

RESUMO

Rechargeable aqueous zinc-ion batteries (AZIBs) have developed into one of the most attractive materials for large-scale energy storage owing to their advantages such as high energy density, low cost, and environmental friendliness. Nevertheless, the sluggish diffusion kinetics and inherent impoverished conductivity affect their practical application. Herein, the ß-MnO2 composited with carbon nanotubes (CNT@M) is prepared through a simple hydrothermal approach as a high-performance cathode for AZIBs. The CNT@M electrode exhibits excellent cycling stability, in which the maximum specific discharge capacity is 259 mA h g-1 at 3 A g-1, and there is still 220 mA h g-1 after 2000 cycles. The specific capacity is obviously better than that of ß-MnO2 (32 mA h g-1 after 2000 cycles). The outstanding electrochemical performance of the battery is inseparable from the structural framework of CNT and inherent high conductivity. Furthermore, CNT@M can form a complex conductive network based on CNTs to provide excellent ion diffusion and charge transfer. Therefore, the active material can maintain a long-term cycle and achieve stable capacity retention. This research provides a reasonable solution for the reliable conception of Mn-based electrodes and indicates its potential application in high-performance AZIB cathode materials.

2.
Angew Chem Int Ed Engl ; : e202409763, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38954763

RESUMO

Developing non-platinum group metal catalysts for the sluggish hydrogen oxidation reaction (HOR) is critical for alkaline fuel cells. To date, Ni-based materials are the most promising candidates but still suffer from insufficient performance. Herein, we report an unconventional hcp/fcc Ni (u-hcp/fcc Ni) heteronanocrystal with multiple epitaxial hcp/fcc heterointerfaces and coherent twin boundaries, generating rugged surfaces with plenty of asymmetric convex sites. Systematic analyses discover that such convex sites enable the adsorption of *H in unusual bridge positions with weakened binding energy, circumventing the over-strong *H adsorption on traditional hollow positions, and simultaneously stabilizing interfacial *H2O. It thus synergistically optimizes the HOR thermodynamic process as well as reduces the kinetic barrier of the rate-determining Volmer step. Consequently, the developed u-hcp/fcc Ni exhibits the top-rank alkaline HOR activity with a mass activity of 40.6 mA mgNi-1 (6.3 times higher than fcc Ni control) together with superior stability and high CO-tolerance. These results provide a paradigm for designing high-performance catalysts by shifting the adsorption state of intermediates through configuring surface sites.

3.
J Cancer Res Clin Oncol ; 150(5): 239, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38713252

RESUMO

PURPOSE: Multiple myeloma (MM) is an incurable hematological malignancy characterized by clonal proliferation of malignant plasma B cells in bone marrow, and its pathogenesis remains unknown. The aim of this study was to determine the role of kinesin family member 22 (KIF22) in MM and elucidate its molecular mechanism. METHODS: The expression of KIF22 was detected in MM patients based upon the public datasets and clinical samples. Then, in vitro assays were performed to investigate the biological function of KIF22 in MM cell lines, and subcutaneous xenograft models in nude mice were conducted in vivo. Chromatin immunoprecipitation (ChIP) and luciferase reporter assay were used to determine the mechanism of KIF22-mediated regulation. RESULTS: The results demonstrated that the expression of KIF22 in MM patients was associated with several clinical features, including gender (P = 0.016), LDH (P < 0.001), ß2-MG (P = 0.003), percentage of tumor cells (BM) (P = 0.002) and poor prognosis (P < 0.0001). Furthermore, changing the expression of KIF22 mainly influenced the cell proliferation in vitro and tumor growth in vivo, and caused G2/M phase cell cycle dysfunction. Mechanically, KIF22 directly transcriptionally regulated cell division cycle 25C (CDC25C) by binding its promoter and indirectly influenced CDC25C expression by regulating the ERK pathway. KIF22 also regulated CDC25C/CDK1/cyclinB1 pathway. CONCLUSION: KIF22 could promote cell proliferation and cell cycle progression by transcriptionally regulating CDC25C and its downstream CDC25C/CDK1/cyclinB1 pathway to facilitate MM progression, which might be a potential therapeutic target in MM.


Assuntos
Proteína Quinase CDC2 , Ciclina B1 , Proteínas de Ligação a DNA , Cinesinas , Mieloma Múltiplo , Fosfatases cdc25 , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Proteína Quinase CDC2/metabolismo , Proteína Quinase CDC2/genética , Fosfatases cdc25/metabolismo , Fosfatases cdc25/genética , Linhagem Celular Tumoral , Proliferação de Células , Ciclina B1/metabolismo , Ciclina B1/genética , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Cinesinas/metabolismo , Cinesinas/genética , Camundongos Endogâmicos BALB C , Camundongos Nus , Mieloma Múltiplo/patologia , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/genética , Prognóstico , Transdução de Sinais
4.
J Phys Chem Lett ; 15(11): 3011-3022, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38465884

RESUMO

The severe performance degradation of low-temperature hydrogen fuel cells upon exposure to trace amounts of carbon monoxide (CO) impurities in reformate hydrogen fuels is one of the challenges that hinders their commercialization. Despite significant efforts that have been made, the CO-tolerance performance of electrocatalysts for the hydrogen oxidation reaction (HOR) is still unsatisfactory. This Perspective discusses the path forward for the rational design of CO-tolerant HOR electrocatalysts. The fundamentals of the CO-tolerant mechanisms on commercialized platinum group metal (PGM) electrocatalysts via either promoting CO electrooxidation or weakening CO adsorption are provided, and comprehensive discussions based on these strategies are presented with typical examples. Given the recent progress, some emerging strategies, including blocking CO diffusion with a barrier layer and developing non-PGM HOR catalysts, are also discussed. We conclude with a discussion of the strengths and limitations of these strategies along with the perspectives of the major challenges and opportunities for future research on CO-tolerant HOR electrocatalysts.

5.
J Am Chem Soc ; 146(9): 6345-6351, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38377535

RESUMO

Selenium (Se) discovered in 1817 belongs to the family of chalcogens. Surprisingly, despite the long history of over two centuries and the chemical simplicity of Se, the structure of amorphous Se (a-Se) remains controversial to date regarding the dominance of chains versus rings. Here, we find that vapor-deposited a-Se is composed of disordered rings rather than chains in melt-quenched a-Se. We further reveal that the main origin of this controversy is the facile transition of rings to chains arising from the inherent instability of rings. This transition can be inadvertently triggered by certain characterization techniques themselves containing above-bandgap illumination (above 2.1 eV) or heating (above 50 °C). We finally build a roadmap for obtaining accurate Raman spectra by using above-bandgap excitation lasers with low photon flux (below 1017 phs m-2 s-1) and below-bandgap excitation lasers measured at low temperatures (below -40 °C) to minimize the photoexcitation- and heat-induced ring-to-chain transitions.

6.
Angew Chem Int Ed Engl ; 63(17): e202317794, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38424035

RESUMO

Tin halide perovskites (THPs) have demonstrated exceptional potential for various applications owing to their low toxicity and excellent optoelectronic properties. However, the crystallization kinetics of THPs are less controllable than its lead counterpart because of the higher Lewis acidity of Sn2+, leading to THP films with poor morphology and rampant defects. Here, a colloidal zeta potential modulation approach is developed to improve the crystallization kinetics of THP films inspired by the classical Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. After adding 3-aminopyrrolidine dihydro iodate (APDI2) in the precursor solution to change the zeta potential of the pristine colloids, the total interaction potential energy between colloidal particles with APDI2 could be controllably reduced, resulting in a higher coagulation probability and a lower critical nuclei concentration. In situ laser light scattering measurements confirmed the increased nucleation rate of the THP colloids with APDI2. The resulting film with APDI2 shows a pinhole-free morphology with fewer defects, achieving an impressive efficiency of 15.13 %.

7.
Angew Chem Int Ed Engl ; 63(10): e202318591, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38230583

RESUMO

The thermally stable inorganic cesium-based perovskites promise efficient and stable photovoltaics. Unfortunately, the strong ionic bonds lead to uncontrollable rapid crystallization, making it difficult in fabricating large-area black-phase film for photovoltaics. Herein, we developed a facile hydrogen-bonding assisted strategy for modulating the crystallization of CsPbI2 Br to achieve uniform large-area phase-pure films with much-reduced defects. The simple addition of methylamine acetate in precursors not only promotes the formation of intermediate phase via hydrogen bonding to circumvent the direct crystallization of CsPbI2 Br from ionic precursors but also widens the film processing window, thus enabling to fabricate large-area high-quality phase-pure CsPbI2 Br film under benign conditions. Combining with stable dopant-free poly(3-hexylthiophene), the CsPbI2 Br solar cells achieve the record-high efficiencies of 18.14 % and 16.46 % for 0.1 cm2 and 1 cm2 active area, respectively. The obtained high efficiency of 38.24 % under 1000 lux illumination suggests its potential in indoor photovoltaics for powering the Internet of Things, etc.

8.
Small Methods ; 8(1): e2300957, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37802971

RESUMO

Electrochemically converting CO2 back into fuels and chemicals is promising in alleviating the greenhouse effect worldwide. Various high-efficiency catalysts have been achieved, yet the unsatisfied structural stability under CO2 electrolysis conditions restricts their practical application. Herein, a sub-5 nm sized CuInS2 quantum dots (CIS-QDs) based electrocatalyst for converting CO2 into CO are developed. Taking advantage of the stable M─Ch (metal-chalcogenide) covalent bonds, and unique p-block metal properties, the as-prepared catalyst exhibits excellent structural stability under large overpotentials and can achieve a high CO Faradaic efficiency (FE) of 86% (total CO2 reduction FE of 89%) at -0.65 V versus reversible hydrogen electrode with long-term durability of 40 h and outstanding current densities of 10.6 mA cm-2 simultaneously. Furthermore, detailed electrochemical analyses revealed that the excellent performance of the as-prepared catalysts shall be attributed to the high-density active sites and fast charge transfer brought by the ultrasmall size of CIS-QDs. This work provides insights into the design of high-density and stable catalytic sites for developing high-performance electrocatalysts.

9.
Chemosphere ; 342: 140190, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37716558

RESUMO

Heteroatom doping, involving the introduction of atoms with distinct electronegativity into carbon materials, has emerged as an effective approach to optimize their charge distribution. In this study, we designed a strategy to synthesize in-situ Mn, N co-doped carbon nanospheres (Mn-NC) through the polycondensation of 2,6-diaminopyridine and formaldehyde in synchronization with Mn2+ chelation to form Mn-polytriazine precursor, followed by calcination to form carbonaceous solid. Then Mn-NC was fabricated into a capacitive deionization (CDI) electrode for the selective removal of uranium ions (U (VI)), which is commonly found in radioactive water. Interestingly, Mn-NC exhibited good selectivity for UO22+ capture with a demonstrated adsorption capacity of approximately 194 mg/g @1.8 V. The systematic analysis of the adsorption mechanism of UO22+ revealed that N dopants within Mn-NC can coordinate with the U (VI) ions, thereby facilitating the removal process. Our study presents a straightforward and convenient strategy for removing UO22+ ions by harnessing the coordination effect, eliminating the requirement for pore size control.

10.
Sci Rep ; 13(1): 12422, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37528177

RESUMO

In this study, we conducted direct synthesis of a dual metal-organic framework (Ni/Co-Hemin MOF) on phosphorous-doped reduced graphene oxide (PrGO) to serve as an active material in high-performance asymmetrical supercapacitors. The nanocomposite was utilized as an active material in supercapacitors, exhibiting a noteworthy specific capacitance of 963 C g-1 at 1.0 A g-1, along with a high rate capability of 68.3% upon increasing the current density by 20 times, and superior cycling stability. Our comprehensive characterization and control experiments indicated that the improved performance can be attributed to the combined effect of the dual MOF and the presence of phosphorous, influencing the battery-type supercapacitor behavior of GO. Additionally, we fabricated an asymmetric hybrid supercapacitor (AHSC) using Ni/Co-Hemin/PrGO/Nickel foam (NF) and activated carbon (AC)/NF. This AHSC demonstrated a specific capacitance of 281 C g-1 at 1.0 A g-1, an operating voltage of 1.80 V, an impressive energy density of 70.3 Wh kg-1 at a high power density of 0.9 kW kg-1. Notably, three AHSC devices connected in series successfully powered a clock for approximately 42 min. These findings highlight the potential application of Hemin-based MOFs in advanced supercapacitor systems.

11.
Small Methods ; 7(11): e2300574, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37572004

RESUMO

Aqueous zinc-ion batteries are promising energy storage devices due to their low cost, good ionic conductivity, and high safety. Conductive polyaniline is a promising cathode because of its redox activity, but because the neutral electrolyte protonates only weakly, it displays limited electrochemical activity. A polyaniline cathode is developed with proton self-doping from manganese metal-organic frameworks (Mn-MOFs) that alleviates the deprotonation and electrochemical activity concerns arising during the charge/discharge process. The MOFs carboxyl group provides protons to prevent deprotonation and allows the polyaniline to reach a high zinc storage redox activity. The proton self-doped polyaniline cathode has a superior specific capacity (273 mAh g-1 at 0.5 A g-1 ), a high rate property (154 mAh g-1 at 20 A g-1 ), and excellent cyclability retention (87% over 4000 cycles at 15 A g-1 ). This research provides fresh insight into the development of innovative polymers as cathode materials for high-performance AZIBs.

12.
J Am Chem Soc ; 145(25): 13805-13815, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37317527

RESUMO

The alkaline hydrogen oxidation reaction (HOR) involves the coupling of adsorbed hydrogen (Had) and hydroxyl (OHad) species and is thus orders of magnitude slower than that in acid media. According to the Sabatier principle, developing electrocatalysts with appropriate binding energy for both intermediates is vital to accelerating the HOR though it is still challenging. Herein, we propose an unconventional bilateral compressive strained Ni-Ir interface (Ni-Ir(BCS)) as efficient synergistic HOR sites. Density functional theory (DFT) simulations reveal that the bilateral compressive strain effect leads to the appropriate adsorption for both Had and OHad, enabling their coupling thermodynamically spontaneous and kinetically preferential. Such Ni-Ir(BCS) is experimentally achieved by embedding sub-nanometer Ir clusters in graphene-loaded high-density Ni nanocrystals (Ni-Ir(BCS)/G). As predicted, it exhibits a HOR mass activity of 7.95 and 2.88 times those of commercial Ir/C and Pt/C together with much enhanced CO tolerance, respectively, ranking among the most active state-of-the-art HOR catalysts. These results provide new insights into the rational design of advanced electrocatalysts involving coordinated adsorption and activation of multiple reactants.

13.
Natl Sci Rev ; 10(4): nwac248, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37180356

RESUMO

Electrochemical CO2 reduction (ECR) to high-value multi-carbon (C2+) products is critical to sustainable energy conversion, yet the high energy barrier of C-C coupling causes catalysts to suffer high overpotential and low selectivity toward specific liquid C2+ products. Here, the electronically asymmetric Cu-Cu/Cu-N-C (Cu/CuNC) interface site is found, by theoretical calculations, to enhance the adsorption of *CO intermediates and decrease the reaction barrier of C-C coupling in ECR, enabling efficient C-C coupling at low overpotential. The catalyst consisting of high-density Cu/CuNC interface sites (noted as ER-Cu/CuNC) is then accordingly designed and constructed in situ on the high-loading Cu-N-C single atomic catalysts. Systematical experiments corroborate the theoretical prediction that the ER-Cu/CuNC boosts electrocatalytic CO2-to-ethanol conversion with a Faradaic efficiency toward C2+ of 60.3% (FEethanol of 55%) at a low overpotential of -0.35 V. These findings provide new insights and an attractive approach to creating electronically asymmetric dual sites for efficient conversion of CO2 to C2+ products.

14.
J Colloid Interface Sci ; 642: 714-723, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37037077

RESUMO

The realization of the membrane-free two-step water electrolysis is particularly important yet challenging for the low-cost and large-scale supply of hydrogen energy. In this effort, Co-doped Ni(OH)2 nanosheets were successfully anchored onto the nickel foam (NF) substrate through the in-situ growth of metal-organic frame material and the subsequent alkali-etching technique. Using the well-regulated Co-doping Ni(OH)2@NF electrodes as a charge mediator, electrochemical hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) were decoupled on time scales, thus affording a membrane-free two-step route for H2 and O2 productions. In this architecture, the first HER process on the cathode could be maintained for 1300 s at a current of 100 mA, while the corresponding Ni(OH)2 charge mediator was simultaneously oxidized to NiOOH, with a decent cell voltage of 1.542 V. The subsequent OER process involved a reduction/regeneration of Ni(OH)2 (from NiOOH to Ni(OH)2) and an anodic O2-production, with an operating voltage of 0.291 V. Moreover, the Ni-Zn battery assembled through the combination of NiOOH and Zn sheet could replace the second step of OER to achieve the coupling of continuous H2-production and battery discharge, thus also providing a new way for hydrogen production without an external power supply. Experiment and theoretical calculations have shown that the cobalt-doping not only improved the conductivity of the charge-buffer electrode, but also shifted its redox potential cathodically and boosted the adsorption affinity of the buffer medium to OH- ions, both contributing to promoted HER and OER activity. Therefore, this decoupled water electrolysis device affords a promising pathway to support the efficient conversion of renewables to hydrogen.

15.
Nat Commun ; 14(1): 1822, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37005416

RESUMO

Anion-exchange membrane fuel cells and Zn-air batteries based on non-Pt group metal catalysts typically suffer from sluggish cathodic oxygen reduction. Designing advanced catalyst architectures to improve the catalyst's oxygen reduction activity and boosting the accessible site density by increasing metal loading and site utilization are potential ways to achieve high device performances. Herein, we report an interfacial assembly strategy to achieve binary single-atomic Fe/Co-Nx with high mass loadings through constructing a nanocage structure and concentrating high-density accessible binary single-atomic Fe/Co-Nx sites in a porous shell. The prepared FeCo-NCH features metal loading with a single-atomic distribution as high as 7.9 wt% and an accessible site density of around 7.6 × 1019 sites g-1, surpassing most reported M-Nx catalysts. In anion exchange membrane fuel cells and zinc-air batteries, the FeCo-NCH material delivers peak power densities of 569.0 or 414.5 mW cm-2, 3.4 or 2.8 times higher than control devices assembled with FeCo-NC. These results suggest that the present strategy for promoting catalytic site utilization offers new possibilities for exploring efficient low-cost electrocatalysts to boost the performance of various energy devices.

16.
Oncogene ; 42(20): 1607-1619, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37012388

RESUMO

Multiple myeloma (MM) is the second most common hematological malignancy. N6-methyladenosine (m6A) is the most abundant RNA modification. YTH domain-containing family protein 2 (YTHDF2) recognizes m6A-cotaining RNAs and accelerates degradation to regulate cancer progression. However, the role of YTHDF2 in MM remains unclear. We investigated the expression levels and prognostic role of YTHDF2 in MM, and studied the effect of YTHDF2 on MM proliferation and cell cycle. The results showed that YTHDF2 was highly expressed in MM and was an independent prognostic factor for MM survival. Silencing YTHDF2 suppressed cell proliferation and caused the G1/S phase cell cycle arrest. RNA immunoprecipitation (RIP) and m6A-RIP (MeRIP) revealed that YTHDF2 accelerated EGR1 mRNA degradation in an m6A-dependent manner. Moreover, overexpression of YTHDF2 promoted MM growth via the m6A-dependent degradation of EGR1 both in vitro and in vivo. Furthermore, EGR1 suppressed cell proliferation and retarded cell cycle by activating p21cip1/waf1 transcription and inhibiting CDK2-cyclinE1. EGR1 knockdown could reverse the inhibited proliferation and cell cycle arrest upon YTHDF2 knockdown. In conclusion, the high expression of YTHDF2 promoted MM cell proliferation via EGR1/p21cip1/waf1/CDK2-cyclin E1 axis-mediated cell cycle transition, highlighting the potential of YTHDF2 as an effective prognostic biomarker and a promising therapeutic target for MM.


Assuntos
Mieloma Múltiplo , Humanos , Ciclo Celular/fisiologia , Proliferação de Células , Quinase 2 Dependente de Ciclina/genética , Quinase 2 Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Mieloma Múltiplo/genética , RNA , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Fatores de Transcrição/metabolismo
17.
J Colloid Interface Sci ; 642: 513-522, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37028158

RESUMO

Aqueous zinc-ion batteries (AZIBs) have shown great potential as energy storage devices owing to their high energy density, low cost, and low toxicity. Typically, high performance AZIBs incorporate manganese-based cathode materials. Despite their advantages, these cathodes are limited by significant capacity fading and poor rate performance due to the dissolution and disproportionation of manganese. Herein, hierarchical spheroidal MnO@C structures were synthesized from Mn-based metal-organic frameworks, which benefit from a protective carbon layer to prevent manganese dissolution. The spheroidal MnO@C structures were incorporated onto a heterogeneous interface to act as a cathode material for AZIBs, which exhibited excellent cycling stability (160 mAh g-1 after 1000 cycles at 3.0 A g-1), good rate capability (165.9 mAh g-1 at 3.0 A g-1), and appreciable specific capacity (412.4 mAh g-1 at 0.1 A g-1) for AZIBs. Moreover, the Zn2+ storage mechanism in MnO@C was comprehensively investigated using ex-situ XRD and XPS studies. These results demonstrate that hierarchical spheroidal MnO@C is a potential cathode material for high-performing AZIBs.

18.
J Am Chem Soc ; 145(10): 5872-5879, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36872583

RESUMO

Passivating defects using organic halide salts, especially chlorides, is an effective method to improve power conversion efficiencies (PCEs) of perovskite solar cells (PSCs) arising from the stronger Pb-Cl bonding than Pb-I and Pb-Br bonding. However, Cl- anions with a small radius are prone to incorporation into the perovskite lattice that distorts the lead halide octahedron, degrading the photovoltaic performance. Here, we substitute atomic-Cl-containing organic molecules for widely used ionic-Cl salts, which not only retain the efficient passivation by Cl but also prevent the incorporation of Cl into the bulk lattice, benefiting from the strong covalent bonding between Cl atoms and organic frameworks. We find that only when the distance of Cl atoms in single molecules matches well with the distance of halide ions in perovskites can such a configuration maximize the defect passivation. We thereby optimize the molecular configuration to enable multiple Cl atoms in an optimal spatial position to maximize their binding with surface defects. The resulting PSCs achieve a certified PCE of 25.02%, among the highest PCEs for PSCs, and retain 90% of their initial PCE after 500 h of continuous operation.

19.
J Thorac Dis ; 15(2): 452-461, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36910077

RESUMO

Background: At a crucial time with the rapid spread of Omicron severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus variant globally, we conducted a study to evaluate the efficacy and safety of arbidol tablets in the treatment of this variant. Methods: From Mar 26 to April 26, 2022, we conducted a prospective, open-labeled, controlled, and investigator-initiated trial involving adult patients with confirmed Omicron variant infection. Patients with asymptomatic or mild clinical status were stratified 1:2 to receive either standard-of-care (SOC) or SOC plus arbidol tablets (oral administration of 200 mg per time, three times a day for 5 days). The primary endpoint was the negative conversion rate within the first week. Results: A total of 367 patients were enrolled in the study; 246 received arbidol tablet treatment, and 121 were in the control group. The negative conversion rate of SARS-CoV-2 within the first week in patients receiving arbidol tablets was significantly higher than that of the SOC group [47.2% (116/246) vs. 35.5% (43/121); odds ratio (OR), 1.619; 95% confidence interval (CI): 1.034-2.535; P=0.035]. Compared to those in the SOC group, patients receiving arbidol tablets had a shorter negative conversion time [median 8.3 vs. 10.0 days; hazard ratio (HR), 0.645; 95% CI: 0.516-0.808; P<0.001], and a shorter duration of hospitalization (median 11.4 vs. 13.7 days; HR, 1.214; 95% CI: 0.966-1.526; P<0.001). Moreover, the addition of arbidol tablets led to better recovery of declined blood lymphocytes, CD3+, CD4+, and CD8+ cell counts. The most common adverse event (AE) was transaminase elevation in patients treated with arbidol tablets (3/246, 1.2%). No one withdrew from the study due to AEs or disease progression. Conclusions: As a whole, arbidol may represent an effective and safe treatment in asymptomatic-mild patients suffering from Omicron variant during the pandemic of coronavirus disease 2019 (COVID-19).

20.
Artigo em Inglês | MEDLINE | ID: mdl-36901650

RESUMO

To achieve SDGs (sustainable development goals) and carbon neutrality goals, the Chinese government have been adopting the cap-and-trade regulation to curb carbon emissions. With this background, members in the supply chain should properly arrange their carbon reduction and marketing decisions to acquire optimal profits, especially when the favorable event may happen, which tends to elevate goodwill and the market demand. However, the event may not be of their benefit when the cap-and-trade regulation is conducted, since the increase in market demand is always associated with an increase in carbon emissions. Hence, questions arise about how the members adjust their carbon reduction and marketing decisions while envisioning the favorable event under the cap-and-trade regulation. Given the fact that the event occurs randomly during the planning period, we use the Markov random process to depict the event and use differential game methodology to dynamically study this issue. After solving and analyzing the model, we acquire the following conclusions: (1) the occurrence of the favorable event splits the whole planning period into two regimes and the supply chain members should make optimal decisions in each regime to maximize the overall profits. (2) The potential favorable event will elevate the marketing and carbon reduction efforts, as well as the goodwill level before the event. (3) If the unit emissions value is relatively low, the favorable event will help to decrease the emissions quantity. However, if the unit emissions value is relatively large, then the favorable event will help to increase the emissions quantity.


Assuntos
Carbono , Tomada de Decisões , Marketing , Comércio
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