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1.
Small ; : e2402105, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38727184

RESUMO

The scarcity of fresh water necessitates sustainable and efficient water desalination strategies. Solar-driven steam generation (SSG), which employs solar energy for water evaporation, has emerged as a promising approach. Graphene oxide (GO)-based membranes possess advantages like capillary action and Marangoni effect, but their stacking defects and dead zones of flexible flakes hinders efficient water transportation, thus the evaporation rate lag behind unobstructed-porous 3D evaporators. Therefore, fundamental mass-transfer approach for optimizing SSG evaporators offers new horizons. Herein, a universal multi-force-fields-based method is presented to regularize membrane channels, which can mechanically eliminate inherent interlayer stackings and defects. Both characterization and simulation demonstrate the effectiveness of this approach across different scales and explain the intrinsic mechanism of mass-transfer enhancement. When combined with a structurally optimized substrate, the 4Laponite@GO-1 achieves evaporation rate of 2.782 kg m-2 h-1 with 94.48% evaporation efficiency, which is comparable with most 3D evaporators. Moreover, the optimized membrane exhibits excellent cycling stability (10 days) and tolerance to extreme conditions (pH 1-14, salinity 1%-15%), verifies the robust structural stability of regularized channels. This optimization strategy provides simple but efficient way to enhance the SSG performance of GO-based membranes, facilitating their extensive application in sustainable water purification technologies.

2.
Phys Rev Lett ; 130(14): 146801, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37084445

RESUMO

Two-dimensional (2D) ferroelectrics, which are rare in nature, enable high-density nonvolatile memory with low energy consumption. Here, we propose a theory of bilayer stacking ferroelectricity (BSF), in which two stacked layers of the same 2D material, with different rotation and translation, exhibit ferroelectricity. By performing systematic group theory analysis, we find all the possible BSF in all 80 layer groups (LGs) and discover the rules about the creation and annihilation of symmetries in the bilayer. Our general theory can not only explain all the previous findings (including sliding ferroelectricity), but also provide a new perspective. Interestingly, the direction of the electric polarization of the bilayer could be totally different from that of the single layer. In particular, the bilayer could become ferroelectric after properly stacking two centrosymmetric nonpolar monolayers. By means of first-principles simulations, we predict that the ferroelectricity and thus multiferroicity can be introduced to the prototypical 2D ferromagnetic centrosymmetric material CrI_{3} by stacking. Furthermore, we find that the out-of-plane electric polarization in bilayer CrI_{3} is interlocked with the in-plane electric polarization, suggesting that the out-of-plane polarization can be manipulated in a deterministic way through the application of an in-plane electric field. The present BSF theory lays a solid foundation for designing a large number of bilayer ferroelectrics and thus colorful platforms for fundamental studies and applications.

3.
J Am Chem Soc ; 144(32): 14907-14914, 2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-35926166

RESUMO

Organic-inorganic multiferroics are promising for the next generation of electronic devices. To date, dozens of organic-inorganic multiferroics have been reported; however, most of them show a magnetic Curie temperature much lower than room temperature, which drastically hampers their application. Here, by performing first-principles calculations and building effective model Hamiltonians, we reveal a molecular orbital-mediated magnetic coupling mechanism in two-dimensional Cr(pyz)2 (pyz = pyrazine) and the role that the valence state of the molecule plays in determining the magnetic coupling type between metal ions. Based on these, we demonstrate that a two-dimensional organic-inorganic room-temperature multiferroic, Cr(h-fpyz)2 (h-fpyz = half-fluoropyrazine), can be rationally designed by introducing ferroelectricity in Cr(pyz)2 while keeping the valence state of the molecule unchanged. Our work not only reveals the origin of magnetic coupling in 2D organic-inorganic systems but also provides a way to design room-temperature multiferroic materials rationally.

4.
Macromol Rapid Commun ; 42(16): e2100232, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34121263

RESUMO

Ionic species are important to dominate phase separation behaviors of poly(N-isopropylacrylamide) (PNIPAm) in aqueous solutions. Herein, photoresponsive azobenzene-based salts with various ions are prepared and their photoresponsive ion effects on clouding temperatures (TcpS ) of PNIPAm in aqueous solutions are explored. It is found that, despite of various structures of anions and cations, trans-TcpS under vis light irradiation are always higher than cis-TcpS under UV irradiation. Particularly, Hofmeister effect of anions on TcpS is roughly observed. For example, azobenzene with kosmotropic CO3 2- gives the lowest cis-Tcp while in use of typical chaotropic anions, such as ClO4 - , azobenzene isomerization less affects values of Tcp s. In another hand, azobenzene-based metallic salts containing lithium, sodium, and potassium cations also demonstrate photoresponsive Hofmeister effect. Trans-metallic azobenzene demonstrates a chaotropic effect on Tcp s while UV induces kosmotropic behaviors on TcpS . Additionally, ionic conduction of the solution along with photoresponsive phase separations is also investigated and PNIPAm aggregations induce a sharp reduction of ion conduction during UV light illumination.


Assuntos
Resinas Acrílicas , Sais , Compostos Azo , Cátions
5.
J Immunol ; 201(1): 243-250, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29777027

RESUMO

Inflammatory bowel disease has been associated with the dysregulation of T cells specific to Ags derived from the intestinal microbiota. How microbiota-specific T cells are regulated is not completely clear but is believed to be mediated by a combination of IgA, regulatory T cells, and type 3 innate lymphoid cells. To test the role of these regulatory components on microbiota-specific T cells, we bred CBir1 TCR transgenic (CBir1Tg) mice (specific to flagellin from common intestinal bacteria) onto a lymphopenic Rag1-/- background. Surprisingly, T cells from CBir1Tg mice bred onto a Rag1-/- background could not induce colitis and did not differentiate to become effectors under lymphopenic conditions, despite deficits in immunoregulatory factors, such as IgA, regulatory T cells, and type 3 innate lymphoid cells. In fact, upon transfer of conventional CBir1Tg T cells into lymphopenic mice, the vast majority of proliferating T cells responded to Ags other than CBir1 flagellin, including those found on other bacteria, such as Helicobacter spp. Thus, we discovered a caveat in the CBir1Tg model within our animal facility that illustrates the limitations of using TCR transgenics at mucosal surfaces, where multiple TCR specificities can respond to the plethora of foreign Ags. Our findings also indicate that T cell specificity to the microbiota alone is not sufficient to induce T cell activation and colitis. Instead, other interrelated factors, such as the composition and ecology of the intestinal microbiota and host access to Ag, are paramount in controlling the activation of microbiota-specific T cell clones.


Assuntos
Flagelina/imunologia , Microbioma Gastrointestinal/imunologia , Mucosa Intestinal/microbiologia , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Transferência Adotiva , Animais , Proliferação de Células , Células Cultivadas , Colite/metabolismo , Feminino , Helicobacter/imunologia , Imunoglobulina A/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Linfócitos T Auxiliares-Indutores/imunologia
6.
Small ; 15(7): e1804974, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30667601

RESUMO

The dynamic optical switch of plasmonic nanostructures is highly desirable due to its promising applications in many smart optical devices. To address the challenges in the reversibility and transmittance contrast of the plasmonic electrochromic devices, here, a strategy is reported to fabricate color switchable electrochromic films through electro-responsive dissolution and deposition of Ag on predefined hollow shells of Au/Ag alloy. Using the hollow Au/Ag alloy nanostructures as stable seeds for site-specific deposition of Ag, elimination of the random self-nucleation events is enabled and optimal reversibility in color switching is allowed. The hollow structure further enables excellent transmittance contrast between the bleached and colored states. With its additional advantages such as the convenience for preparation, high sensitivity, and field-tunable optical property, it is believed that this new electrochromic film represents a unique platform for designing novel smart optical devices.

7.
Mikrochim Acta ; 185(2): 86, 2018 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-29594721

RESUMO

A platform is described for voltammetric sensing of hydrogen peroxide (H2O2). It is based on the use of nitrogen-doped graphite foam modified with Prussian Blue particles (PB/NGF). Graphite foam was synthesized by chemical vapor deposition, and doping with nitrogen was realized via dielectric barrier plasma discharge. PB particles were grown on the NGF through electrodeposition. SEM images of NGF verified the porous and interconnected structure of graphite foam, and XPS and Raman spectroscopy verified the successful doping with N. The performance of the PB/NGF electrode was characterized by CV and EIS which showed it to possess outstanding properties in terms of sensing H2O2. H2O2 was quantified in a range of 0.004 to 1.6 mM with a detection limit of 2.4 µM. The PB/NGF electrode also is shown to be a viable substrate for loading glucose oxidase (GOx). The GOx-functionalized electrode responds to glucose over the 0.2 to 20 mM concentration range at a potential of -50 mV (vs. Ag/AgCl), with a sensitivity of 27.48 mA M-1 cm-2 and a 0.1 M detection limit (at an S/N ratio of 3). The glucose sensor is selective, stable, and reproducible. The biosensor was successfully applied to the determination of glucose in spiked human serum samples, and this confirmed it practicability. Graphical abstract Schematic of a self-supporting amperometric glucose biosensor based on glucose oxidase and Prussian blue modified 3D nitrogen doped graphite foam.

8.
Phys Chem Chem Phys ; 17(28): 18629-37, 2015 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-26119980

RESUMO

LiMn0.5Fe0.5PO4 (LMFP) materials are synthesized by the hydrothermal approach in an organic-free and surfactant-free aqueous solution. The phase and morphological evolution of the material intermediates at different reaction temperatures and times are characterized by XRD, SEM and TEM, respectively. The results show that during temperature increase, the solubility product (Ksp) of the precursors (Li3PO4, Fe3(PO4)2 and (Mn,Fe)3(PO4)2) is the decisive parameter for the precipitation processes. Once the temperature locates at the range of 100-110 °C, the unstable precursors dissolve quickly and then LMFP nuclei are formed, followed by a dissolution-reprecipitation process. As the reaction progresses, the primary particles self-aggregate to form rod or plate particles to reduce the overall surface energy through oriented attachment (OA) and the Ostwald ripening (OR) mechanism. Moreover, the resultant concentration of the precursor significantly affects the crystal size of LMFP by altering the supersaturation degree of solution at the nucleation stage. The carbon coated LMFP nanostructure synthesized at 0.6 mol L(-1) (resultant concentration of PO4(3-)) delivers discharge capacities of 155, 100 and 81 mA h g(-1) at 0.1, 5 and 20 C rate, respectively. The understanding of nanostructural evolution and its influence on the electrochemical performance will pave a way for a high-performance LMFP cathode.

9.
Nat Commun ; 15(1): 135, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167841

RESUMO

For an ordinary ferroelectric, the magnitude of the spontaneous electric polarization is at least one order of magnitude smaller than that resulting from the ionic displacement of the lattice vectors, and the direction of the spontaneous electric polarization is determined by the point group of the ferroelectric. Here, we introduce a new class of ferroelectricity termed Fractional Quantum Ferroelectricity. Unlike ordinary ferroelectrics, the polarization of Fractional Quantum Ferroelectricity arises from substantial atomic displacements that are comparable to lattice constants. Applying group theory analysis, we identify 28 potential point groups that can realize Fractional Quantum Ferroelectricity, including both polar and non-polar groups. The direction of polarization in Fractional Quantum Ferroelectricity is found to always contradict with the symmetry of the "polar" phase, which violates Neumann's principle, challenging conventional symmetry-based knowledge. Through the Fractional Quantum Ferroelectricity theory and density functional calculations, we not only explain the puzzling experimentally observed in-plane polarization of monolayer α-In2Se3, but also predict polarization in a cubic compound of AgBr. Our findings unveil a new realm of ferroelectric behavior, expanding the understanding and application of these materials beyond the limits of traditional ferroelectrics.

10.
Tissue Eng Part B Rev ; 29(4): 441-455, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36884294

RESUMO

Small-caliber tissue-engineered vascular grafts (TEVGs, luminal diameter <6 mm) are promising therapies for coronary or peripheral artery bypassing surgeries or emergency treatments of vascular trauma, and a robust seed cell source is required for scalable manufacturing of small-caliber TEVGs with robust mechanical strength and bioactive endothelium in future. Human-induced pluripotent stem cells (hiPSCs) could serve as a robust cell source to derive functional vascular seed cells and potentially lead to generation of immunocompatible engineered vascular tissues. Up to date, this rising field of small-caliber hiPSC-derived TEVG (hiPSC-TEVG) research has received increasing attention and achieved significant progress. Implantable, small-caliber, hiPSC-TEVGs have been generated. These hiPSC-TEVGs displayed rupture pressure and suture retention strength approaching to those of human native saphenous veins, with vessel wall decellularized and luminal surface endothelialized with monolayer of hiPSC-endothelial cells. Meanwhile, a series of challenges remain in this field, including functional maturity of hiPSC-derived vascular cells, poor elastogenesis, suboptimal efficiency of obtaining hiPSC-derived seed cells, and relative low ready availability of hiPSC-TEVGs, which are waiting to be addressed. This review is conceived to introduce representative achievements and challenges in small-caliber TEVG generation using hiPSCs, and encapsulate the potential solution and future directions.


Assuntos
Prótese Vascular , Células-Tronco Pluripotentes Induzidas , Humanos , Células Endoteliais , Engenharia Tecidual
11.
ACS Nano ; 17(22): 23194-23206, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37926964

RESUMO

Design of admirable conductive hydrogels combining robust toughness, soft flexibility, desirable conductivity, and freezing resistance remains daunting challenges for meeting the customized and critical demands of flexible and wearable electronics. Herein, a promising and facile strategy to prepare hydrogels tailored to these anticipated demands is proposed, which is prepared in one step by homogeneous cross-linking of acrylamide using hydrophobic divinylbenzene stabilized by micelles under saturated high-saline solutions. The influence of high-saline environments on the hydrogel topology and mechanical performance is investigated. The high-saline environments suppress the size of hydrophobic cross-linkers in micelles during hydrogel polymerization, which weaken the dynamic hydrophobic associations to soften the hydrogels. Nevertheless, the homogeneous cross-linked networks ensure antifracture during ultralarge deformations. The obtained hydrogels show special mechanical performance combining extremely soft deformability and antifracture features (Young's modulus, 5 kPa; stretchability, 10200%; toughness, 134 kJ m-2; and excellent anticrack propagation). The saturated-saline environments also endow the hydrogels with desirable ion conductivity (106 mS cm-1) and freezing resistance (<20 °C). These comprehensive properties of the obtained hydrogels are quite suitable for flexible electronic applications, which is demonstrated by the high sensitivity and durability of the derived strain sensors.

12.
ACS Appl Mater Interfaces ; 15(42): 49892-49901, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37815919

RESUMO

Solar-driven interfacial evaporation (SIE) technology has great advantages in seawater desalination. However, during the long-term operation of a solar evaporator, salts can be deposited on the solar absorbing surface, which, in turn, hinders the evaporation process. Therefore, there is an urgent need to propose new antisalt strategies to solve this problem. Here, we present a novel cogeneration system leveraging a salt-tolerant, heterogeneous Janus-structured evaporator (FHJE) for simultaneous solar desalination and thermoelectric generation. The top evaporation layer is composed of a graphene-based photothermal membrane pre-embedded with Fe3+ cations, which enhanced solar absorption and energy conversion abilities. Meanwhile, the Fe3+ cations further contribute to the Donnan effect, effectively repelling salt ions in saltwater. The bottom layer comprises a hydrogel composed of hydrophilic phytic acid (PA) and poly(vinyl alcohol) (PVA), fostering facilitation of water transport. The FHJE was demonstrated to exhibit evaporation rate and efficiency as high as 3.655 kg m-2 h-1 and 94.7% in 10 wt% saltwater, respectively, and superior salt resistance ability without salt accumulation after 8 h of continuous evaporation (15 wt%). Furthermore, a hydropower cogeneration evaporator device was constructed, and it possesses an open-circuit voltage (VOC) and a maximum output power density of up to 143 mV and 1.33 W m-2 under 1 sun, respectively. This study is expected to provide new ideas for comprehensive utilization of solar energy.

13.
J Colloid Interface Sci ; 644: 167-176, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37105040

RESUMO

The self-standing graphene membranes are considered as ideal electrode materials for supercapacitors. However, maintaining highly regularized and uniform graphene membranes with satisfied electrochemical performance is still a challenge. Herein, with the chelation of metal cation and the radial shear force introduced by high-speed spinning, the uniform interlayer channels and shrunken cracks between adjacent nanosheets can be achieved in the metal-intercalated graphene oxide (GO) membranes, thus realizing regularization both in normal and radial direction. With the promotion in electron transfer and electrolyte penetration, the iron cross-linked GO membrane with spin coating for 40 cycles exhibits a high specific capacitance (427 F g-1 at 1 A g-1) and rate capability (42.6% capacitance retention from 1 to 40 A g-1), as well as excellent cyclic capability (90.5% capacitance retention after 20,000 cycles). Particularly, a 21% increasement in capacitance can be achieved after high-speed spinning treatment. Moreover, the spin regularization strategy can be extended to GO membranes cross-linked by various multi-valence metal cations, the electrochemical performance of metal-cation cross-linked GO membrane electrodes after high-speed spinning treatment can also be improved obviously. Therefore, this paper provides a novel method to fabricate highly ordered GO membranes with promising electrochemical performance, which presents an immense potential application in membrane materials applied in energy storage, separation and catalysis.

14.
J Colloid Interface Sci ; 629(Pt B): 1039-1048, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36209567

RESUMO

Oxygen vacancies occupation and coordination environment modulation of the transition-metal based electrodes are effective strategies to improve the structural stability and electrochemical performance. In this work, the 2-methylimidazole (2-MI) doped manganese dioxide (MnO2) anchored on carbon cloth (CC) is fabricated via a simple method (MI-MnO2-x/CC), where the oxygen defects on/inside the K+ doped δ-MnO2 nanosheets are in-situ created by reductive ethanol/Mn2+ and occupied by 2-MI ligands. With the pre-embedded K+ ions and abundant ligand-refilled defects, the electronic coordination structure, structural stability and electron/ion diffusion efficiency can be effectively enhanced. Therefore, the MI-MnO2-x/CC reveals a remarkable specific capacitance of 721.2 mF cm-2 with excellent cycle durability (capacitance retention of 93.4% after 10,000 cycles) under 1.3 V operation potential window. In addition, an asymmetric supercapacitor assembled by MI-MnO2-x/CC and activated mechanical exfoliated graphene oxide yields a maximum energy density of 57.0 Wh kg-1 and a highest power density of 23.0 kW kg-1 under 2.3 V. This effective oxygen defect stabilization strategy by ligands refilling can be extended to various metal oxide-based electrodes for energy storage and conversion.

15.
ACS Appl Mater Interfaces ; 15(22): 27089-27098, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37226077

RESUMO

Developing cost-effective Pt-based electrocatalysts for the hydrogen evolution reaction (HER) is highly urgent. Herein, we report novel electrocatalysts with individually dispersed Pt active sites and tunable Pt-Ni interaction decorated on carbon-wrapped nanotube frameworks (Pt/Ni-DA). Pt/Ni-DA exhibits superior HER performance at low Pt concentrations with an ultralow overpotential of 18 mV at 10 mA cm-2 and an ultrahigh mass activity of 2.13 A mgPt-1 at an overpotential of 50 mV, which is about four times higher than that of commercial Pt/C. X-ray absorption fine structure (XAFS) confirms the extension of Pt from the Ni surface to the Ni bulk phase. Mechanistic research and density functional theory (DFT) calculations collectively reveal that the dispersibility and distribution of Pt atoms in Ni regulate the electronic configuration of Pt sites, optimizing the binding energy of reaction intermediates and facilitating electron transfer during the HER process. This work highlights the importance of the electronic structure alternation through the accommodation effect toward enhanced catalytic performance in HER.

16.
Cell Mol Gastroenterol Hepatol ; 16(2): 287-316, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37172822

RESUMO

BACKGROUND & AIMS: The colonic epithelium requires continuous renewal by crypt resident intestinal stem cells (ISCs) and transit-amplifying (TA) cells to maintain barrier integrity, especially after inflammatory damage. The diet of high-income countries contains increasing amounts of sugar, such as sucrose. ISCs and TA cells are sensitive to dietary metabolites, but whether excess sugar affects their function directly is unknown. METHODS: Here, we used a combination of 3-dimensional colonoids and a mouse model of colon damage/repair (dextran sodium sulfate colitis) to show the direct effect of sugar on the transcriptional, metabolic, and regenerative functions of crypt ISCs and TA cells. RESULTS: We show that high-sugar conditions directly limit murine and human colonoid development, which is associated with a reduction in the expression of proliferative genes, adenosine triphosphate levels, and the accumulation of pyruvate. Treatment of colonoids with dichloroacetate, which forces pyruvate into the tricarboxylic acid cycle, restored their growth. In concert, dextran sodium sulfate treatment of mice fed a high-sugar diet led to massive irreparable damage that was independent of the colonic microbiota and its metabolites. Analyses on crypt cells from high-sucrose-fed mice showed a reduction in the expression of ISC genes, impeded proliferative potential, and increased glycolytic potential without a commensurate increase in aerobic respiration. CONCLUSIONS: Taken together, our results indicate that short-term, excess dietary sucrose can directly modulate intestinal crypt cell metabolism and inhibit ISC/TA cell regenerative proliferation. This knowledge may inform diets that better support the treatment of acute intestinal injury.


Assuntos
Colite , Açúcares da Dieta , Camundongos , Humanos , Animais , Dextranos , Colite/metabolismo , Piruvatos
17.
J Colloid Interface Sci ; 624: 51-59, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35660910

RESUMO

Tailoring the porous structure of carbon materials is one essential approach to improve the energy storage performance of carbon-based electrode materials. Herein, hierarchical porous carbons (HPCs) with different meso-structure are synthesized via a one-pot pyrolysis process with SiO2 and ZnCl2 as template and activator, respectively. The energy storage capacities of the obtained HPC samples are investigated as bi-functional electrode both for supercapacitor and LIBs. The results show that different meso-structure of HPCs can effectively affect the energy storage performance. In the range of 15 âˆ¼ 50 nm, smaller size of mesopore can result better electrochemical performance of HPCs. And the optimized HPC sample (HPC-15) manifests high specific capacitance of 432F g-1 and good cyclic stability in the supercapacitor application. When used as anode of LIBs, the HPC-15 presents a high capacity of 820 mAh g-1. In addition, COMSOL simulation is employed to study the effect of pore structure on mass transfer during electrochemical process. The HPC-15 is calculated to have the highest total porosity (εp) and effective diffusivity of K+ (De = 6.776 × 10-10 m2 s-1), thus leading to its best electrochemical performance.

18.
Front Immunol ; 12: 677957, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335579

RESUMO

Patients with inflammatory bowel disease, psoriasis or other rheumatic diseases treated with corticosteroids, immunomodulators and biologics might face additional risk during COVID-19 epidemic due to their immunocompromised status. However, there was still no unanimous opinion on the use of these therapy during COVID-19 epidemic. Current studies suggested that systemic corticosteroids might increase the risk of hospitalization, as well as risks of ventilation, ICU, and death among patients with immune-mediated inflammatory diseases. Anti-TNF agent was associated with lower rate of hospitalization, as well as lower risks of ventilation, ICU, and death. No significant changes in rates of hospitalization, ventilation, ICU and mortality were observed in patients treated with immunomodulators or biologics apart from anti-TNF agents. The underlying mechanism of these results might be related to pathway of antiviral immune response and cytokine storm induced by SARS-COV-2 infection. Decision on the use of corticosteroids, immunomodulators and biologics should be made after weighing the benefits and potential risks based on individual patients.


Assuntos
Corticosteroides/uso terapêutico , Produtos Biológicos/uso terapêutico , Tratamento Farmacológico da COVID-19 , Síndrome da Liberação de Citocina/tratamento farmacológico , Imunossupressores/uso terapêutico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Psoríase/tratamento farmacológico , Doenças Reumáticas/tratamento farmacológico , SARS-CoV-2/fisiologia , Inibidores do Fator de Necrose Tumoral/uso terapêutico , COVID-19/mortalidade , Síndrome da Liberação de Citocina/mortalidade , Hospitalização , Humanos , Imunidade , Doenças Inflamatórias Intestinais/mortalidade , Psoríase/mortalidade , Doenças Reumáticas/mortalidade , Risco , Análise de Sobrevida
19.
ACS Appl Mater Interfaces ; 13(35): 41545-41554, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34432425

RESUMO

Developing highly active water splitting electrocatalysts with ordered micro/nanostructures and uniformly distributed active sites can meet the increasing requirement for sustainable energy storage/utilization technologies. However, the stability of complicated structures and active sites during a long-term process is also a challenge. Herein, we fabricate a novel approach to create sufficient atomic defects via N2 plasma treatment onto parallel aligned NiMoO4 nanosheets, followed by refilling of these defects via heterocation dopants and stabilizing them by annealing. The parallel aligned nanosheet arrays with an open structure and quasi-two-dimensional long-range diffusion channels can accelerate the mass transfer at the electrolyte/gas interface, while the incorporation of Fe/Pt atoms into defect sites can modulate the local electronic environment and facilitate the adsorption/reaction kinetics. The optimized Pt-NP-NMC/CC-5 and Fe-NP-NMC/CC-10 electrodes exhibit low overpotentials of 71 and 241 mV at 10 mA cm-2 for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER), respectively, and the assembled device reveals a low voltage of 1.55 V for overall water splitting. This plasma-induced high-efficiency defect engineering and coupled active site stabilization strategy can be extended to large-scale fabrication of high-end electrocatalysts.

20.
J Colloid Interface Sci ; 587: 855-863, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33246655

RESUMO

The rational structure design and controllable surface modification of electrode materials plays a decisive role in constructing high performance energy storage and conversion devices. Herein, the P-doped cobalt carbonate hydroxide@NiMoO4 (P-CoCH@NiMoO4) nanowires@nanosheets double-shell hierarchical structure is successfully fabricated on nickel foam. The unique nanowire@nanosheet structure with gradient porous distribution and hydrophilic nature can facilitate both the charge and electron transfer based on the synergetic effects with conductive NiMoO4 array. Importantly, the dopant of P element can enrich oxygen vacancies on the surface of CoCH nanowire, thus increase the effective active sites and enhance the electrocatalytic performance. Therefore, when act as the supercapacitor electrode, the bi-functional P-CoCH@NiMoO4/NF material achieves high areal capacitance (5.08 F cm-2 at 2 mA cm-2, 0.75 mAh cm-2) and good cyclic stability (82.7% capacitance retention after 2000 cycles). Meanwhile, when utilize as the hydrogen evolution electrode in alkaline solution, a low overpotential (115 mV at 10 mA cm-2) and Tafel slope (113.5 mV dec-1) can also be achieved.

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