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Interleukin-17 s (IL-17s) are well-known proinflammatory cytokines, and their antagonists perform excellently in the treatment of inflammatory skin diseases such as psoriasis. However, their physiological functions have not been given sufficient attention by clinicians. IL-17s can protect the host from extracellular pathogens, maintain epithelial integrity, regulate cognitive processes and modulate adipocyte activity through distinct mechanisms. Here, we present a systematic review concerning the physiological functions of IL-17s. Our goal is not to negate the therapeutic effect of IL-17 antagonists, but to ensure their safe use and reasonably explain the possible adverse events that may occur in their application.
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Interleucina-17 , Psoríase , Humanos , Citocinas , Psoríase/tratamento farmacológicoRESUMO
The development of K-based layered oxide cathodes is essential for boosting the competitiveness of potassium-ion batteries (PIBs) in grid-scale energy storage. However, their service life is dramatically limited by interfacial instability issues, which is still poorly understood. In this work, amorphous FePO4 (a-FP) is built on K0.5 Ni0.1 Mn0.9 O2 (KNMO) as the protective skin, whose elasticity for strain relaxation and the K-conducting nature guarantee its integrity during fast and constant K-ion insertion/extraction. The conformal coating leads to a robust interphase on the cathode surface, which qualifies excellent K-transport ability and significantly suppresses the mechanical cracking and transition metal dissolution. Breakthrough in cycle life of the K-based layered cathodes is therefore achieved, which of the amorphous FePO4 coated K0.5 Ni0.1 Mn0.9 O2 (KNMO@a-FP) reaches 2500 cycles. The insights gained from the surface protection layer construction and the in-depth analysis of its working mechanism pave the way for further development of K-based layered cathodes with both bulk structural and interfacial stability.
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Metallic zinc is regarded as an ideal anode material for high-energy aqueous zinc ion batteries owing to its high theoretical capacity, low cost, and abundant resource. However, the undesirable dendrite formation and side reactions occurring on Zn anode during the long-term cycling process seriously restrict the electrochemical performance of the device. Herein, 1-hydroxy ethylidene-1,1-diphosphonic acid (HEDP) is used as electrolyte additive to release the chemical corrosion and hydrogen evolution occurring on Zn anode based on the absorption of HEDP on the Zn foil. Moreover, the strong coordination of HEDP with Zn2+ can balance ion flux at the electrode/electrolyte interface, thus inducing uniform Zn deposition. Thereby, Zn anode exhibits a prolonged cycle life of reversible Zn plating/stripping under different current densities (2800 h at 2 mA cm-2 , 1 mAh cm-2 , and more than 1772 h at 4 mA cm-2 , 1 mAh cm-2 ). Moreover, the cell shows a high average coulombic efficiency of ≈99.6% for ≈600 cycles at 1 mA cm-2 with a cycling capacity of 1 mAh cm-2 . This work provides a facile yet effective method for developing reversible aqueous zinc metal batteries.
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The amount of silicon in anode materials for Li-ion batteries is still limited by the huge volume changes during charge-discharge cycles. Such changes lead to the loss of electrical contacts, as well as mechanical and surface electrolyte interphase (SEI) instabilities, strongly reducing the cycle life. Core-shell structures have attracted a vast research interest due to the possibility of modifying some properties with a judicious choice of the shell. It is, for example, possible to improve the electronic conductivity and ionic diffusion, or buffer volume variations. This review gives a comprehensive overview of the recent developments and the different strategies used for the design, synthesis and electrochemical performance of silicon-based core-shells. It is based on a selection of the main types of silicon coatings reported in the literature, including carbon, inorganic, organic and double-layer coatings, Finally, a summary of the advantages and drawbacks of these different types of core-shells as anode materials for Li-ion batteries and some insightful suggestions in regards to their use are provided.
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Metastable intermediates represent a non-equilibrium state of matter that may impose profound impacts to materials properties beyond our understandings of monolithic and equilibrium systems. Here, we report a discovery of hidden metastable intermediates in amorphous TiO2 thin films and their critical role in electrochemical damage. These intermediates have a non-bulk crystal-like structure and exhibit significantly higher electrical conductivity than both the amorphous and the crystalline phases. When these TiO2 films are applied to protect Si photoelectrochemical (PEC) photoanodes, the intermediates can induce localized high electrical currents that largely accelerate the etching of the TiO2 film and the Si electrode underneath. The intermediates can be effectively suppressed by raising their nucleation barrier via reducing the film thickness from 24 to 2.5 nm. The homogeneous amorphous TiO2-film-coated Si photoanodes achieved more than 500 h of PEC water oxidation at a steady photocurrent density of over 30 mA·cm-2.
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Central venous catheters (CVCs) are implanted in the majority of dialysis patients despite increased patient risk due to thrombotic occlusion and biofilm formation. Current solutions remain ineffective at preventing these complications and treatment options are limited and often harmful. We present further analysis of the previously proposed water infused surface protection (WISP) technology, an active method to reduce protein adsorption and effectively disrupt adsorbed protein sheaths on the inner surface of CVCs. A WISP CVC is modeled by a hollow fiber membrane (HFM) in a benchtop device which continuously infuses a saline solution across the membrane wall into the blood flow, creating a blood-free boundary layer at the lumen surface. Total protein adsorption is measured under various experimental conditions to further test WISP performance. The WISP device shows reduced protein adsorption as blood and WISP flow rates increase (P < 0.040) with up to a 96% reduction in adsorption over the no WISP condition. When heparin is added to the WISP flow, protein adsorption (0.097[+0.035/-0.055] µg/mm2 ) is reduced when compared to both bolus administration and nondoped WISP, 0.406(+0.056/-0.065) µg/mm2 (P = 0.001) and 0.191 (+0.076/-0.126) (P = 0.029), respectively. Additionally, when heparinized WISP is applied to a preadsorbed protein layer, 0.375(+0.114/-0.164) µg/mm2 , it displays the ability to reduce the previously-adsorbed protein, 0.186(+0.058/-0.084) µg/mm2 (P = 0.0012), suggesting aptitude for intermittent treatments. The WISP technology not only shows the ability to reduce protein adsorption, but also the ability to remove preadsorbed material by effectively delivering drugs to the point of adsorption; functionalities that could greatly improve clinical outcomes.
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Proteínas Sanguíneas/isolamento & purificação , Cateteres Venosos Centrais , Trombose/prevenção & controle , Adsorção , Anticoagulantes/química , Cateterismo Venoso Central/efeitos adversos , Cateteres Venosos Centrais/efeitos adversos , Heparina/química , Humanos , Propriedades de Superfície , Trombose/etiologia , Água/químicaRESUMO
When nanocrystals are made to undergo chemical transformations, there are often accompanying large mechanical deformations and changes to overall particle morphology. These effects can constrain development of multistep synthetic methods through loss of well-defined particle morphology and functionality. Here, we demonstrate a surface protection strategy for solution phase chemical conversion of colloidal nanostructures that allows for preservation of overall particle morphology despite large volume changes. Specifically, via stabilization with strong coordinating capping ligands, we demonstrate the effectiveness of this method by transforming ß-FeOOH nanorods into magnetic Fe3O4 nanorods, which are known to be difficult to produce directly. The surface-protected conversion strategy is believed to represent a general self-templating method for nanocrystal synthesis, as confirmed by applying it to the chemical conversion of nanostructures of other morphologies (spheres, rods, cubes, and plates) and compositions (hydroxides, oxides, and metal organic frameworks).
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Protein adhesion in central venous catheters (CVCs) leads to fibrin sheath formation, the precursor to thrombotic and biofilm-related CVC failures. Advances in material properties and surface coatings do not completely prevent fibrin sheath formation and post-formation treatment options are limited and expensive. We propose water infused surface protection (WISP), an active method for prevention of fibrin sheath formation on CVCs, which creates a blood-free boundary layer on the inner surface of the CVC, limiting blood contact with the CVC lumen wall. A hollow fiber membrane (HFM) in a benchtop device served as a CVC testing model to demonstrate the WISP concept. Porcine blood was pumped through the HFM while phosphate buffered saline (PBS) was infused through the HFM wall, creating the WISP boundary layer. Protein adherences on model CVC surfaces were measured and imaged. Analytical and finite volume lubrication models were used to justify the assumption of a blood-free boundary layer. We found a 92.2% reduction in average adherent protein density when WISP is used, compared with our model CVC without WISP flow. Lubrication models matched our experimental pressure drop measurements suggesting that a blood-free boundary layer was created. The WISP technique also provides a novel strategy for drug administration for biofilm treatment. Reduction in adherent protein indicates a restriction on long-term fibrin sheath and biofilm formation making WISP a promising technology which improves a wide range of vascular access treatments.
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Cateteres Venosos Centrais/efeitos adversos , Fibrina/química , Trombose/etiologia , Água/química , Adsorção , Animais , Desenho de Equipamento , Humanos , Lubrificação , Teste de Materiais , Propriedades de Superfície , Suínos , Trombose/prevenção & controleRESUMO
A retrospective audit was conducted of four patients with upper eyelid gold weights (inserted >5 years ago) as treatment for facial nerve palsy-related lagophthalmos. Each patient was presently examined for lagophthalmos ("opened" or "closed") at three different patient inclinations (lying flat at 0º, lying back at 45º, and sitting upright at 90º). In all four cases at 0º inclination, the upper eyelid remained "open" with significant lagophthalmos, and therefore the ocular surface was vulnerable. At other inclinations, 45º and 90º, the eyes were substantially "closed" and the ocular surface was protected. We discuss the mechanism by which this occurs. We suggest that patients fitted with upper eyelid gold weight implant who do not show adequate closure during postoperative clinical examination or signs of corneal show should try sleeping in a slightly upright position to aid ocular surface protection.
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Doenças Palpebrais/cirurgia , Pálpebras/fisiologia , Paralisia Facial/cirurgia , Ouro , Postura/fisiologia , Próteses e Implantes , Adulto , Idoso , Doenças Palpebrais/fisiopatologia , Paralisia Facial/fisiopatologia , Feminino , Gravitação , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
The beneficial effect of microbially induced carbonate precipitation on building materials has been gradually disclosed in the last decade. After the first applications of on historical stones, promising results were obtained with the respect of improved durability. An extensive study then followed on the application of this environmentally friendly and compatible material on a currently widely used construction material, concrete. This review is focused on the discussion of the impact of the two main applications, bacterial surface treatment and bacteria based crack repair, on concrete durability. Special attention was paid to the choice of suitable bacteria and the metabolic pathway aiming at their functionality in concrete environment. Interactions between bacterial cells and cementitious matrix were also elaborated. Furthermore, recommendations to improve the effectiveness of bacterial treatment are provided. Limitations of current studies, updated applications and future application perspectives are shortly outlined.
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Bacillus megaterium/metabolismo , Bacillus/metabolismo , Carbonato de Cálcio/química , Materiais de Construção/microbiologia , Sporosarcina/metabolismo , Bacillus/química , Bacillus megaterium/química , Carbonato de Cálcio/metabolismo , Precipitação Química , Dureza , Teste de Materiais , Redes e Vias Metabólicas/fisiologia , Sporosarcina/química , Propriedades de SuperfícieRESUMO
Rare Earth elements (REE) such as NdFeB are commonly used to produce permanent magnets. Thanks to their superior properties, these materials are highly desirable for green energy applications such as wind power generators or electric cars. Currently, REEs are critical for the ongoing development of eco-friendly solutions in different industrial branches. The emerging issue of REE depletion has led to a need for new methods to enable the life cycle elongation, resistance to wear, and external factors improvement of NdFeB magnets. This can be achieved by advanced, nanostructured coating formation of magnet surfaces to increase their functionality and protect from humidity, pressure, temperature, and other factors. The aim of the following research was to develop a new, scalable strategy for the modification of NdFeB magnets using laser-assisted technique, also known as Laser cladding. For this purpose, four different micropowders were used to modify commercial NdFeB samples. The products were investigated for their morphology, structure, chemical composition, and crystallography. Moreover, magnetic flux density was evaluated. Our results showed that laser cladding constitutes a promising strategy for REE-based permanent magnets modification and regeneration and may help to improve durability and resistance of NdFeB components.
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Building formwork is a kind of temporary supporting structure consumable material used in the construction field. In recent years, building formwork has gradually developed to become lighter, more environmentally friendly, and have higher performance. This sets higher requirements for the materials used to make building formwork. There is an urgent need to find a lighter and more durable material for building formwork. Magnesium alloys possess the advantages of low density, high alkali resistance, and high strength. As a building formwork material, it can reduce the weight of formwork and improve its durability. Therefore, a magnesium alloy is considered a material with high potential for building formwork. Currently, magnesium alloy building formwork has attracted the attention of many companies and research and development institutions, with preliminary research applications and good feedback on usage effects. It is highly possible to obtain the opportunity to put it into market application. However, to be applied on a large scale, there are still some important problems that need to be solved. These problems fall into three main areas, including the relatively low processing efficiency of magnesium alloy materials, the unstable price of magnesium alloys, and the fact that the formwork is easily corroded during storage. Firstly, at present, the main processing methods for magnesium alloy building formwork are casting and extrusion, and the production efficiency of both methods needs to be improved. Secondly, high-performance magnesium alloy materials are usually more expensive, which is not conducive to the large-scale application of the formwork. The price of magnesium alloys has fluctuated greatly in recent years, which increases the difficulty of promoting magnesium alloy building formwork. Thirdly, in the atmosphere, the oxide film on the surface of the magnesium alloy cannot play an effective role in corrosion resistance. So, surface treatment is necessary for magnesium alloy building formwork. Among the various surface treatment methods for magnesium alloys, the chemical conversion method has the advantages of being easy to operate, cost-effective, and having good corrosion resistance. It may be a very suitable protective method for large-scale applications of magnesium alloy building formwork and possesses excellent potential for application. The future of magnesium alloy building formwork will focus on new low-cost materials, high-efficiency processing technology, and low-cost green anti-corrosion technology. With in-depth research and the maturation of technology, magnesium alloy formwork is expected to play a more important role in the construction industry.
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Developing anti-biofouling and anti-biofilm techniques is of great importance for protecting water-contact surfaces. In this study, we developed a novel double-layer system consisting of a bottom immobilized TiO2 nanoflower arrays (TNFs) unit and an upper superhydrophobic (SHB) coating along with the assistance of nanobubbles (NBs), which can significantly elevate the interfacial oxygen level by establishing the long-range hydrophobic force between NBs and SHB and effectively maximize the photocatalytic reaction brought by the bottom TNFs. The developed NBs-SHB/TNFs system demonstrated the highest bulk chemical oxygen demand (COD) reduction efficiency at approximately 80% and achieved significant E. coli and Chlorella sp. inhibition efficiencies of 5.38 and 1.99 logs. Meanwhile, the system showed a sevenfold higher resistance to biofilm formation when testing in a wastewater matrix using a wildly collected biofilm seeding solution. These findings provide insights for implementing nanobubble-integrated techniques for submerged surface protection.
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Incrustação Biológica , Chlorella , Escherichia coli , Incrustação Biológica/prevenção & controle , Biofilmes , Interações Hidrofóbicas e HidrofílicasRESUMO
The protection of building elements exposed to the weather using hydrocarbon-based agents is a comprehensive group of analyses. These agents are characterized by very high chemical resistance, waterproofness, as well as adhesion to surfaces made of various materials, i.e., concrete, steel, ceramics and wood. Modification of adhesion, which ultimately leads to an increase in the durability of a protective/face coating made of such a material, can lead to a longer life of these layers and a less frequent need for replacement or restoration. The following paper describes an experimental research program on the possibility of increasing the adhesion and durability of epoxy resin modified with the use of powder fillers. The resin can be used as a protective or top coat on the surface of concretes or mortars. The main objective of the study was to increase the adhesion of the resin to the concrete substrate, modified by grinding and sandblasting to increase the roughness. For the series studied, both the changes in physicochemical parameters, which determine how the resin penetrates the irregularities of the substrate and mechanical parameters, which mainly determine the durability of the layer made in this way, were identified. A modified version of the pull-off test was used as a method to directly evaluate the effectiveness of the modified resins.
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Erosion caused by the repeated impact of particles on the surface of a substance is a common wear method resulting in the gradual and continual loss of affected objects. It is a crucial problem in several modern industries because the surfaces of various products and materials are frequently subjected to destructively erosive situations. Polymers and their hybrid materials are suitable, in powdered form, for use as coatings in several different applications. This review paper aims to provide extensive information on the erosion behaviors of thermoset and thermoplastic neat resin and their hybrid material composites. Specific attention is paid to the influence of the properties of selected materials and to impingement parameters such as the incident angle of the erodent, the impact velocity of the erodent, the nature of the erodent, and the erosion mechanism. The review further extends the information available about the erosion techniques and numerical simulation methods used for wear studies of surfaces. An investigation was carried out to allow researchers to explore the available selection of materials and methods in terms of the conditions and parameters necessary to meet current and future needs and challenges, in technologically advanced industries, relating to the protection of surfaces. During the review, which was conducted on the findings in the literature of the past fifty years, it was noted that the thermoplastic nature of composites is a key component in determining their anti-wear properties; moreover, composites with lower glass transition, higher ductility, and greater crystallinity provide better protection against erosion in advanced surface applications.
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The energy density of batteries with lithium cobalt oxide (LCO) can be maximized by increasing the cut-off voltage to approach the theoretical capacity limit. However, it is not realized in the practical applications due to the restricted cycle life caused by vulnerable cathode surface in deep delithiation state, where severe side reactions, oxygen/cobalt loss and structure degradation often happen. Here, an outside-in oriented nanostructure on LiCoO2 crystals is fabricated. The outer electrochemically stable LiF and Li2 CoTi3 O8 particles perform as physical barrier to prevent damage of both cathodes and electrolytes, while the inner F doping promote Li ions diffusivity and stabilize the lattice oxygen. With the spinel-like transition layer between them, a solid and complete lithium-ion transport channel generation along the lithium concentration gradient. Under the protection from this structure, the LiCoO2 withstand the high voltage of 4.6 V and the LCO/graphite pouch full cell with high loading density exhibits 81.52% energy density retention after 135 cycles at 4.5 V.
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Photo-electrochemical (PEC) water splitting systems using oxide-based photoelectrodes are highly attractive for solar-to-chemical energy conversion. However, despite decades-long efforts, it is still challenging to develop efficient and stable photoelectrodes for practical applications. Here, thin layers of covalent triazine frameworks (CTF-BTh) containing a bithiophene moiety are conformably deposited onto the surfaces of a Cu2 O photocathode and a Mo-doped BiVO4 photoanode via electropolymerization to construct new hybrid photoelectrodes, successfully addressing the efficiency and stability issues. The CTF-BTh possesses a suitable band structure to form favorable band edge alignment with each metal oxide, creating a p-n junction and a staggered type-II heterojunction with Cu2 O and Mo-doped BiVO4 , respectively. Thus, the as-fabricated hybrid photoelectrodes exhibit substantially increased PEC performances. Meanwhile, the CTF-BTh film also serves as an effective corrosion-resistant overlayer for both photoelectrodes to inhibit photocorrosion and enable long-term operation for 150 h with only ≈10% loss in photocurrent densities. Furthermore, a stand-alone unbiased PEC tandem device comprising CTF-BTh-coated photoelectrodes exhibits 3.70% solar-to-hydrogen conversion efficiency. Even after continuous operation for 120 h, the efficiency can still retain at 3.24%.
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Conversion coatings are one of the primary types of galvanic coatings used to protect steel structures against corrosion. They are created through chemical reactions between the metal surface and the environment of the phosphating. This paper investigates the impact that the addition of new metal cations to the phosphating reaction environment has on the quality of the final coating. So far, standard phosphate coatings have contained only one primary element, such as zinc in the case of zinc coatings, or two elements, such as manganese and iron in the case of manganese coatings. The structural properties have been determined using a scanning electron microscope (SEM), X-ray diffraction (XRD), and electrochemical tests. New manganese coatings were produced through a reaction between the modified phosphating bath and the metal (Ba, Zn, Cd, Mo, Cu, Ce, Sr, and Ca). This change was noticeable in the structure of the produced manganese phosphate crystallites. A destructive effect of molybdenum and chromium was demonstrated. Microscopic analysis, XRD analysis and electrochemical tests suggest that the addition of new metal cations to the phosphating bath affects the corrosion resistance of the modified coating.
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Antifouling surfaces with optimized conformation and compositional heterogeneities are presented with the goal of improving the efficacy of surface protection. The approach exploits the adhesive group (thiol or catechol chain end) to anchor asymmetric polymer brushes (APBs) bearing amphiphilic side chains with synergistic nonfouling and fouling-release abilities onto the surface. The conformation of the APB surface is close to the fencelike structure, which mimics lubricating protein lubricin, endowing the surface with capacity of enhanced protection and antiadhesivity, even facing the high compression of fouling. By utilizing a poly(Br-acrylate-alkyne) macroagent comprising alkynyl and 2-bromopropionate groups, we prepared a series of APB surfaces based on polyacrylate-g-poly(ethylene oxide)/poly(pentafluorophenyl methacrylate) (PA-g-PEO/PPFMA) APBs to explore the influence of the content of the fluorinated segment and bioinspired topological polymer chemistry on their antifouling performance. The APB surfaces can not only provide compositional heterogeneities of PEO and fluorinated segments in each side chain but also give a high surface coverage because of the characteristic of high grafting density of macromolecular brushes. It was found for the first time, as far as we are aware, the fencelike APB surface shows excellent antifouling performance with less protein adsorption (up to 91% off) and cell adhesion (up to 84% off) in comparison with the controlled substrate under relatively long incubation time.
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Adesivos/farmacologia , Biomimética , Adesão Celular/efeitos dos fármacos , Propriedades de Superfície/efeitos dos fármacos , Adesivos/química , Adsorção/efeitos dos fármacos , Alcinos/química , Catecóis/química , Catecóis/farmacologia , Metacrilatos/química , Metacrilatos/farmacologia , Conformação Molecular , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Polímeros/química , Polímeros/farmacologia , Compostos de Sulfidrila/química , Compostos de Sulfidrila/farmacologiaRESUMO
Ni-rich Li[NixCoyMn1-x-y]O2 (NCM) cathode materials have attracted great research interest owing to their high energy density and relatively low cost. However, capacity fading because of parasitic side reactions, mainly occurring at the interface with the electrolyte, still hinders widespread application in advanced Li-ion batteries (LIBs). Surface modification via coating is a feasible approach to tackle this issue. Nevertheless, achieving uniform coatings is challenging, especially when using wet chemistry methods. In this work, a protective alumina shell on NCM701515 (70% Ni) was prepared through the reaction of surface-active -OH groups with trimethylaluminum as the precursor. The coated NCM701515 shows significantly improved capacity retention over uncoated (pristine) NCM701515. Part of the reason is the lower impedance buildup during cycling due to the effective suppression of adverse side reactions and secondary particle fracture. Taken together, the solution-based coating strategy described herein offers an easy way to apply surface treatment to stabilize Ni-rich NCM cathode materials in next-generation LIBs.