Stroke and myocardial infarction are among the most common causes of mortality and disability in the world. The ischemic injury underlying these illnesses is complex, involving intricate interplays ...among many biological functions including energy metabolism, vascular regulation, hemodynamics, oxidative stress, inflammation, platelet activation, and tissue repair that take place in a context- and time-dependent manner. The current drug therapy of choice is to timely resupply the blood to the ischemic tissue; but reperfusion may introduce additional harm to the tissue through a process known as ischemia/reperfusion injury. As such, new drugs that would complement reperfusion by providing neural and cardiovascular protection and by targeting multiple abnormalities in ischemia are receiving increased attention. Scutellarin is an herbal flavonoid glucuronide with multiple pharmacological activities. Owing to its multiple beneficial effects, such as anti-oxidant, anti-inflammation, vascular relaxation, anti-platelet, anti-coagulation, and myocardial protection, scutellarin has been used clinically to treat stroke, myocardial infarction, and diabetic complications. Over the past three decades, clinical and pharmacological studies have accumulated a body of evidence that not only demonstrated these therapeutic effects, but also provided significant insights into the pharmacokinetic behavior, therapeutic profile, and mode of action of scutellarin in humans and animal models. Medicinal modification and new drug delivery methods have led to the development of new derivatives and formulations of scutellarin with improved bioavailability, efficacy, and safety. Here we review the current literature on scutellarin to provide a comprehensive understanding of the pharmacological activity, mechanism of action, toxicity, and therapeutic potential of scutellarin for the treatment of ischemia, diabetic complications, and other chronic diseases.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
In this work, we numerically investigate the radiative properties of metamaterial nanostructures made of two-dimensional tungsten gratings on a thin dielectric spacer and an opaque tungsten film from ...UV to mid-infrared region as potential selective solar absorbers. The metamaterial absorber with single-sized tungsten patches exhibits high absorptance in the visible and near-infrared region due to several mechanisms such as surface plasmon polaritons, magnetic polaritons, and intrinsic bandgap absorption of tungsten. Geometric effects on the resonance wavelengths and the absorptance spectra are studied, and the physical mechanisms are elucidated in detail. The absorptance could be further enhanced in a broader spectral range with double-sized metamaterial absorbers. The total solar absorptance of the optimized metamaterial absorbers at normal incidence could be more than 88%, while the total emittance is less than 3% at 100°C, resulting in total photon-to-heat conversion efficiency of 86% without any optical concentration. Moreover, the metamaterial solar absorbers exhibit quasi-diffuse behaviors as well as polarization independence. The results here will facilitate the design of novel highly efficient solar absorbers to enhance the performance of various solar energy conversion systems.
Hydrothermal carbonization is an important thermochemical conversion process that can be used as an energy-efficient alternative to enhance the dewaterability of sewage sludge and meanwhile to ...convert sewage sludge into high value-added products, such as clean biofuel, organic fertilizer and precursors of functional materials. This paper presents an overview of the latest development of hydrothermal carbonization in the field of sewage sludge treatment, with a particular focus on critical hydrothermal parameters, physicochemical characteristics of products streams, current understanding on hydrochar formation mechanisms, sewage sludge dewaterability improvement and techno-economic advantages. Recent advances have shown that hydrothermal carbonization of sewage sludge is an exothermal process, which is governed by temperature to a large extent. Both polymerizations of highly reactive intermediates derived from degradation of biopolymers in sewage sludge and solid-solid conversion of their undissolved fractions are regarded as the major mechanisms of hydrochar formation. The high ash content of hydrochar is probably the limiting factor for its potential applications in energy and functional materials. The chemistry in hydrothermal carbonization of sewage sludge, closely related to the process parameters and the chemical composition of sewage sludge, offers huge potential to influence the products distribution and characteristics and the process energetics as desired, which provides a promising opportunity to construct a high-efficiency industrial chain for energy and resources recovery from sewage sludge by a controlled hydrothermal process. This review identifies the current challenges and knowledge gaps, and provides new perspectives for future research efforts targeting at sustainable treatment of sewage sludge by hydrothermal carbonization.
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•Latest development of hydrothermal carbonization of sewage sludge is overviewed.•Process parameters and their influence on mechanisms and kinetics are discussed.•Chemistry is identified by organic components conversion and products properties.•Advantages in dewaterability improvement and process energetics are expected.•Potential resource utilization of sludge hydrochar and process water is presented.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Interferon-γ (IFN-γ) plays a key role in activation of cellular immunity and subsequently, stimulation of antitumor immune-response. Based on its cytostatic, pro-apoptotic and antiproliferative ...functions, IFN-γ is considered potentially useful for adjuvant immunotherapy for different types of cancer. Moreover, it IFN-γ may inhibit angiogenesis in tumor tissue, induce regulatory T-cell apoptosis, and/or stimulate the activity of M1 proinflammatory macrophages to overcome tumor progression. However, the current understanding of the roles of IFN-γ in the tumor microenvironment (TME) may be misleading in terms of its clinical application.
Some researchers believe it has anti-tumorigenic properties, while others suggest that it contributes to tumor growth and progression. In our recent work, we have shown that concentration of IFN-γ in the TME determines its function. Further, it was reported that tumors treated with low-dose IFN-γ acquired metastatic properties while those infused with high dose led to tumor regression. Pro-tumorigenic role may be described through IFN-γ signaling insensitivity, downregulation of major histocompatibility complexes, upregulation of indoleamine 2,3-dioxygenase, and checkpoint inhibitors such as programmed cell death ligand 1.
Significant research efforts are required to decipher IFN-γ-dependent pro- and anti-tumorigenic effects. This review discusses the current knowledge concerning the roles of IFN-γ in the TME as a part of the complex immune response to cancer and highlights the importance of identifying IFN-γ responsive patients to improve their sensitivity to immuno-therapies.
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Graphene oxide (GO) is a layered material bearing a variety of oxygen-containing functional groups on its basal planes and edges, which allow it as a substrate to conduct a variety of ...chemical transformations. Here modified graphene oxide (MGO) was prepared using alkyl imidazolium ionic liquids (ILs) (1-butyl-3-methylimidazolium tetrafluoroborate (LB104), 1-butyl-3-methyl imidazolium hexafluorophosphate (LP104) and 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl) amide (LF106)) via epoxide ring-opening reaction, cation-π stacking or van der Waals interactions, with LB104 modified graphene (MG) exfoliated from graphite rod by a moderate electrochemical method as a comparison. The stability and tribological properties of MGO and MG as multialkylated cyclopentanes (MACs) additives were investigated in detail. The results show that GO is converted into graphene through the chemical modification using ILs, and MGO with good dispersion and stability in MACs significantly improves the tribological performance (friction and wear were reduced about 27% and 74% with pure MACs as a comparison, respectively). The excellent tribological properties are attributed to the formation of an ILs-containing graphene-rich tribofilm on the sliding surfaces, which as the third body can prevent the sliding surfaces from straight asperity contact and improve friction reducing and anti-wear behaviors.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
In the present Letter, we theoretically demonstrate that near-field radiative transport between one-dimensional periodic grating microstructures separated by nanometer vacuum gaps can be spectrally ...enhanced by exciting magnetic polaritons. Fluctuational electrodynamics that incorporates scattering matrix theory with rigorous coupled-wave analysis is employed to exactly calculate the near-field radiative flux between two metallic gratings. In addition to the well-known coupled surface plasmon polaritons, the radiative flux can be also spectrally enhanced due to the magnetic polariton, which is excited in the gap between the grating ridges. The mechanism of magnetic polaritons in the near-field radiative transport are elucidated in detail, while the unusual enhancement cannot be predicted by either Derjaguin's or the effective medium approximations. The effects of the vacuum gap distance and grating geometry parameters between the two gratings are investigated. The findings will open a new way to spectrally control near-field radiative transfer by magnetic polaritons with micro- or nanostructured metamaterials, which holds great potential for improving the performance of energy systems like near-field thermophotovoltaics.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
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•NCDs effectively suppress copper corrosion in aggressive acid medium.•NCDs can be designated as a modest cathodic-type inhibitor.•The NCDs–adsorption film involves both physisorption ...and chemisorption.
Researchers recent reported that N-doped carbon dots (NCDs) effectively inhibit steel corrosion in HCl solution, whereas the action mechanism is still uncertain to date. Herein, novel NCDs have been prepared using a facile hydrothermal method. Combining electrochemical, weight loss, and micromorphology techniques, the resultant NCDs were found to effectively suppress copper corrosion in aggressive H2SO4 medium. NCDs–adsorption film was formed on copper substrate as a barrier that could prevent transportation of corrosive particles. The relevant anticorrosion mechanism of NCDs was proposed in detail, which could provide powerful guidance to design and synthesis new nanomaterials for metal protection from corrosion.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This study aims to elucidate the relationship between user demand and library virtual reference services, as well as to explore the development of such services across fifteen colleges and ...universities in China. Leveraging user research data, we established goals for virtual reference services. We introduced the VCRA-CP (Virtual Consultation Resource Allocation-Customer Profile) model for resource scheduling to better align with user needs. User clustering techniques were utilized to categorize users, and a hybrid push information service combining clustering service and collaborative filtering was adopted. This approach was further enhanced by integrating a “user-service evaluation model” to score and deliver services. The operational dynamics of the virtual reference consultation service were meticulously analyzed, particularly focusing on the real-time consulting function module. We proposed evaluating the effectiveness of virtual reference services based on three dimensions: consulting system performance, service impact, and information control. The evaluation metrics included average acceptance value, average perceived value, and average expected value from users. A critical finding concerning the “timeliness and accuracy of responses in virtual reference consultations” revealed a discrepancy, with the average perceived value minus the average acceptance value equaling −0.15, indicating a significant area for improvement in response timeliness and accuracy. User satisfaction was quantified at 65.86%, with a dissatisfaction rate of 6.93%. Although the overall satisfaction with the virtual reference consulting service was high, there remains a need to enhance the standardization of these services to better meet user expectations.
Hydrothermal treatment is an effective method to enhance the deep dewaterability of excess sludge with low energy consumption. In this study, an insight into the relationship between enhanced ...dewaterability and structural properties of the produced hydrothermal sludge was presented, aiming at better understanding the effect of hydrothermal process on excess sludge dewatering performance. The results indicated that hydrothermal effect induced the transformation of surface water to interstitial and free water by lowering the binding strength between adjacent water and solid particles and that free water became the main form for moisture existence in hydrothermal sludge as temperature was higher than 180 °C. Increase in temperature of hydrothermal treatment generated a significant size reduction of sludge flocs but treated sludge with a higher rigidity, which not only strengthened the network of hydrothermal sludge but also destroyed the binding of EPS with water. Hydrothermal process caused crevice and pore structures of excess sludge to disappear gradually, which was a main driving force of water removal as temperature was below 150 °C. With the temperature of hydrothermal treatment exceeding 180 °C, the morphology of hydrothermal sludge became rough which linked closely to the solid precipitation of condensation polymerization, and further became smooth at higher temperature (210 °C) due to the coal-like structures with higher aromaticities, indicating that hydrothermal reaction pathways began to play a main role in enhanced dewaterability. Hydrothermal treatment led to more alkyl and aromatic carbon, but lower O-alkyl, carboxyl and carbonyl carbon.
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•Effect of hydrothermal treatment on water distribution in sludge is identified.•Particle size decrease contributes to enhanced dewaterability of excess sludge.•Disappeared crevice and pore is a driving force for water removal below 150 °C.•Morphology of hydrothermal sludge is related to hydrothermal reaction pathways.•Hydrothermal effect led to more alkyl and aromatic but less O-alkyl and carboxyl.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
A sequence of images, sounds, or words can be stored at several levels of detail, from specific items and their timing to abstract structure. We propose a taxonomy of five distinct cerebral ...mechanisms for sequence coding: transitions and timing knowledge, chunking, ordinal knowledge, algebraic patterns, and nested tree structures. In each case, we review the available experimental paradigms and list the behavioral and neural signatures of the systems involved. Tree structures require a specific recursive neural code, as yet unidentified by electrophysiology, possibly unique to humans, and which may explain the singularity of human language and cognition.
Dehaene et al. review the brain mechanisms of sequence representation. They propose five increasingly abstract levels of representation: transitions and timing, chunking, order, algebraic patterns, and nested trees. They argue that tree structures may be unique to humans.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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