Electrochemical reduction of carbon dioxide (CO2) to value-added chemicals and fuels offers a potential platform to store renewable energy in chemical bonds and thus a route to carbon recycling. Due ...to its high efficiency and reasonable economic feasibility, the conversion of CO2 to carbon monoxide (CO) is considered as the most promising candidate reaction in the industrial market. Recently, the understanding of the basic mechanism of CO2 reduction to CO has become clearer, which has also motivated the design principles for better-performing catalysts including morphology, size, grain boundary, and surface engineering. Various catalysts (noble and non-noble metals, transition metal chalcogenides, carbon materials, and molecular catalysts) have been developed to efficiently catalyze the CO2-to-CO conversion. Here we survey recent key progress in CO2-to-CO conversion in the field of electrocatalytic CO2 reduction. We will highlight the principles of designing electrocatalysts for the selective formation of CO, the influence of electrolytes on the selectivity and conversion rate, and the emerging applications of electrolyzers for large-scale CO production. We finally provide an outlook on several development opportunities that could lead to new advancements in this promising research field.
A considerable challenge in the conversion of carbon dioxide into useful fuels comes from the activation of CO2 to CO2.− or other intermediates, which often requires precious‐metal catalysts, high ...overpotentials, and/or electrolyte additives (e.g., ionic liquids). We report a microwave heating strategy for synthesizing a transition‐metal chalcogenide nanostructure that efficiently catalyzes CO2 electroreduction to carbon monoxide (CO). We found that the cadmium sulfide (CdS) nanoneedle arrays exhibit an unprecedented current density of 212 mA cm−2 with 95.5±4.0 % CO Faraday efficiency at −1.2 V versus a reversible hydrogen electrode (RHE; without iR correction). Experimental and computational studies show that the high‐curvature CdS nanostructured catalyst has a pronounced proximity effect which gives rise to large electric field enhancement, which can concentrate alkali‐metal cations resulting in the enhanced CO2 electroreduction efficiency.
The needle has landed: CdS nanostructures with sharp tips can generate large electric fields that lead to increased CO2 concentrations for CO2‐to‐CO conversion. The localized electric fields are significantly enhanced when two nanoneedles are in close proximity. These advantages result in CO2 electrocatalytic reduction with a 95.5±4.0 % CO Faraday efficiency.
Abstract Hypoxia and lymphangiogenesis are closely related processes that play a pivotal role in tumor invasion and metastasis. Intratumoral hypoxia is exacerbated as a result of oxygen consumption ...by rapidly proliferating tumor cells, insufficient blood supply and poor lymph drainage. Hypoxia induces functional responses in lymphatic endothelial cells (LECs), including cell proliferation and migration. Multiple factors (e.g., ET-1, AP-1, C/EBP-δ, EGR-1, NF-κB, and MIF) are involved in the events of hypoxia-induced lymphangiogenesis. Among them, HIF-1α is known to be the master regulator of cellular oxygen homeostasis, mediating transcriptional activation of lymphangiogenesis via regulation of signaling cascades like VEGF-A/-C/-D, TGF-β and Prox-1 in experimental and human tumors. Although the underlying molecular mechanisms remain incompletely elucidated, the investigation of lymphangiogenesis in hypoxic conditions may provide insight into potential therapeutic targets for lymphatic metastasis.
Cardiac lymphangiogenesis plays an important physiological role in the regulation of interstitial fluid homeostasis, inflammatory, and immune responses. Impaired or excessive cardiac lymphatic ...remodeling and insufficient lymph drainage have been implicated in several cardiovascular diseases including atherosclerosis and myocardial infarction (MI). Although the molecular mechanisms underlying the regulation of functional lymphatics are not fully understood, the interplay between lymphangiogenesis and immune regulation has recently been explored in relation to the initiation and development of these diseases. In this field, experimental therapeutic strategies targeting lymphangiogenesis have shown promise by reducing myocardial inflammation, edema and fibrosis, and improving cardiac function. On the other hand, however, whether lymphangiogenesis is beneficial or detrimental to cardiac transplant survival remains controversial. In the light of recent evidence, cardiac lymphangiogenesis, a thriving and challenging field has been summarized and discussed, which may improve our knowledge in the pathogenesis of cardiovascular diseases and transplant biology.
The lymphatic system provides important functions for tissue fluid homeostasis and immune response. Lymphangiogenesis, the formation of new lymphatics, comprises a series of complex cellular events ...in vitro or in vivo, e.g., proliferation, differentiation, and sprouting. Recent evidence has implied that macrophages act as a direct structural contributor to lymphatic endothelial walls or secret VEGF-C/-D and VEGF-A to initiate lymphangiogenesis in inflamed or tumor tissues. Bone marrow-derived macrophages are versatile cells that express different functional programs in response to exposure to microenvironmental signals, and can be identified by specific expression of a number of proteins, F4/80, CD11b, and CD68. Several causative factors, e.g., NF-κB, IL-1β, TNF-α, SDF-1, M-CSF, especially TonEBP/VEGF-C signaling, may be actively involved in macrophage-induced lymphangiogenesis. Alteration of macrophage phenotype and function has a profound effect on the development and progression of inflammation and malignancy, and macrophage depletion for controlling lymphangiogenesis may provide a novel approach for prevention and treatment of lymphatic-associated diseases.
A novel metal‐organic framework {Zn(XL)2(ClO4)2⋅6 H2O}n (XL=N,N′‐bicyclo2.2.2oct‐7‐ene‐2,3,5,6‐tetracarboxdiimide bi(1,2,4‐triazole)) was synthesized and structurally characterized, presenting the ...first example of six‐fold interpenetrating 3 D framework with the topology type of sqc6, which displays high thermostability and solvent stability. Additionally, the luminescence investigations reveal that this MOF can sensitively and selectively detect acetylacetone with a detection limit of 1.72 ppm. More importantly, it is rather rare for an MOF‐based luminescence probe to serve as a sensor to effectively detect acetylacetone.
Detecting acetylacetone: A novel metal–organic framework, {Zn(XL)2(ClO4)2⋅6 H2O}n, was synthesized and structurally characterized, presenting the first example of a six‐fold interpenetrating 3 D framework with the sqc6 topology and the first example of a transition‐metal MOF‐based luminescence sensor to effectively detect acetylacetone. The detection limit achieved was 1.72 ppm.
Abstract
The management of bacterial infections is becoming a major clinical challenge due to the rapid evolution of antibiotic resistant bacteria. As an excellent candidate to overcome antibiotic ...resistance, antimicrobial peptides (AMPs) that are produced from the synthetic and natural sources demonstrate a broad-spectrum antimicrobial activity with the high specificity and low toxicity. These peptides possess distinctive structures and functions by employing sophisticated mechanisms of action. This comprehensive review provides a broad overview of AMPs from the origin, structural characteristics, mechanisms of action, biological activities to clinical applications. We finally discuss the strategies to optimize and develop AMP-based treatment as the potential antimicrobial and anticancer therapeutics.
Non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome that elevates the risk of hepatocellular carcinoma (HCC). Although alteration of lipid metabolism has ...been increasingly recognized as a hallmark of cancer cells, the deregulated metabolic modulation of HCC cells in the NAFLD progression remains obscure. Here, we discovers an endoplasmic reticulum-residential protein, Nogo-B, as a highly expressed metabolic modulator in both murine and human NAFLD-associated HCCs, which accelerates high-fat, high-carbohydrate diet-induced metabolic dysfunction and tumorigenicity. Mechanistically, CD36-mediated oxLDL uptake triggers CEBPβ expression to directly upregulate Nogo-B, which interacts with ATG5 to promote lipophagy leading to lysophosphatidic acid-enhanced YAP oncogenic activity. This CD36-Nogo-B-YAP pathway consequently reprograms oxLDL metabolism and induces carcinogenetic signaling for NAFLD-associated HCCs. Targeting the Nogo-B pathway may represent a therapeutic strategy for HCC arising from the metabolic syndrome.
Two novel 3D frameworks were synthesized, and further nanosized to form nanospheres. Studies revealed that is the first MOF-based luminescent sensor for detecting cyclohexane, and this is also the ...first time that quick regeneration, high sensitivity, high yield, and easy nanocrystallization of MOF-based luminescent sensors have been simultaneously realized.
We study the surface wrinkling of a stiff thin elastic film bonded to a compliant graded elastic substrate subject to compressive stress generated either by compression or growth of the bilayer. Our ...aim is to clarify the influence of the modulus gradient on the onset and surface pattern in this bilayer. Within the framework of finite elasticity, an exact bifurcation condition is obtained using the Stroh formulation and the surface impedance matrix method. Further analytical progress is made by focusing on the case of short wavelength limit for which the Wentzel–Kramers–Brillouin method can be used to resolve the eigenvalue problem of ordinary differential equations with variable coefficients. An explicit bifurcation condition is obtained from which the critical buckling load and the critical wavelength are derived asymptotically. In particular, we consider two distinct situations depending on the ratio β of the shear modulus at the substrate surface to that at infinity. If β is of O(1) or small, the parameters related to modulus gradient all appear in the higher-order terms and play an insignificant role in the bifurcation. In that case, it is the modulus ratio between the film and substrate surface that governs the onset of surface wrinkling. If, however, β≫1, the modulus gradient affects the critical condition through leading-order terms. Through our analysis we unravel the influence of different material and geometric parameters, including the modulus gradient, on the bifurcation threshold and the associated wavelength which can be of importance in many biological and technological settings.
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