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1.
Sensors (Basel) ; 24(17)2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39275720

RESUMEN

In a production environment, delayed stress recognition can impact yield. Imaging can rapidly and effectively quantify stress symptoms using indexes such as normalized difference vegetation index (NDVI). Commercial systems are effective but cannot be easily customized for specific applications, particularly post-processing. We developed a low-cost customizable imaging system and validated the code to analyze images. Our objective was to verify the image analysis code and custom system could successfully quantify the changes in plant canopy reflectance. 'Supercascade Red', 'Wave© Purple', and 'Carpet Blue' Petunias (Petunia × hybridia) were transplanted individually and subjected to increasing fertilizer treatments and increasing substrate pH in a greenhouse. Treatments for the first trial were the addition of a controlled release fertilizer at six different rates (0, 0.5, 1, 2, 4, and 8 g/pot), and for the second trial, fertilizer solution with four pHs (4, 5.5, 7, and 8.5), with eight replications with one plant each. Plants were imaged twice a week using a commercial imaging system for fertilizer and thrice a week with the custom system for pH. The collected images were analyzed using an in-house program that calculated the indices for each pixel of the plant area. All cultivars showed a significant effect of fertilizer on the projected canopy size and dry weight of the above-substrate biomass and the fertilizer rate treatments (p < 0.01). Plant tissue nitrogen concentration as a function of the applied fertilizer rate showed a significant positive response for all three cultivars (p < 0.001). We verified that the image analysis code successfully quantified the changes in plant canopy reflectance as induced by increasing fertilizer application rate. There was no relationship between the pH and NDVI values for the cultivars tested (p > 0.05). Manganese and phosphorus had no significance with chlorophyll fluorescence for 'Carpet Blue' and 'Wave© Purple' (p > 0.05), though 'Supercascade Red' was found to have significance (p < 0.01). pH did not affect plant canopy size. Chlorophyll fluorescence pixel intensity against the projected canopy size had no significance except in 'Wave© Purple' (p = 0.005). NDVI as a function of the projected canopy size had no statistical significance. We verified the ability of the imaging system with integrated analysis to quantify nutrient deficiency-induced variability in plant canopies by increasing pH levels.


Asunto(s)
Fertilizantes , Petunia , Petunia/fisiología , Concentración de Iones de Hidrógeno , Procesamiento de Imagen Asistido por Computador/métodos
2.
Sensors (Basel) ; 24(17)2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39275428

RESUMEN

Canopy imaging offers a non-destructive, efficient way to objectively measure canopy size, detect stress symptoms, and assess pigment concentrations. While it is faster and easier than traditional destructive methods, manual image analysis, including segmentation and evaluation, can be time-consuming. To make imaging more widely accessible, it's essential to reduce the cost of imaging systems and automate the analysis process. We developed a low-cost imaging system with automated analysis using an embedded microcomputer equipped with a monochrome camera and a filter for a total hardware cost of ~USD 500. Our imaging system takes images under blue, green, red, and infrared light, as well as chlorophyll fluorescence. The system uses a Python-based program to collect and analyze images automatically. The multi-spectral imaging system separates plants from the background using a chlorophyll fluorescence image, which is also used to quantify canopy size. The system then generates normalized difference vegetation index (NDVI, "greenness") images and histograms, providing quantitative, spatially resolved information. We verified that these indices correlate with leaf chlorophyll content and can easily add other indices by installing light sources with the desired spectrums. The low cost of the system can make this imaging technology widely available.


Asunto(s)
Clorofila , Procesamiento de Imagen Asistido por Computador , Hojas de la Planta , Clorofila/análisis , Procesamiento de Imagen Asistido por Computador/métodos , Pigmentación
3.
Sensors (Basel) ; 24(13)2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-39000932

RESUMEN

This paper proposed a fine dust detection system using time-interleaved counters in which surface acoustic wave (SAW) sensors changed the resonance point characteristic. When fine dust was applied to the SAW sensor, the resonance point decreased. The SAW oscillator made of the SAW sensor and radio frequency (RF) amplifier generated an oscillation frequency that was the same as the resonance frequency. The oscillation frequency was transferred to digital data by a 20-bit asynchronous counter. This system has two channels: a sensing channel and a reference channel. Each channel has a SAW oscillator and a 20-bit asynchronous counter. The difference of the two channel counter results is the frequency difference. Through this, it is possible to know whether fine dust adheres to the SAW sensor. The proposed circuit achieved 0.95 ppm frequency resolution when it was operated at a frequency of 460 MHz. This circuit was implemented in a TSMC 130 nm CMOS process.

4.
Nano Lett ; 21(21): 9044-9051, 2021 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-34714657

RESUMEN

The fabrication of battery anodes simultaneously exhibiting large capacity, fast charging capability, and high cyclic stability is challenging because these properties are mutually contrasting in nature. Here, we report a rational strategy to design anodes outperforming the current anodes by simultaneous provision of the above characteristics without utilizing nanomaterials and surface modifications. This is achieved by promoting spontaneous structural evolution of coarse Sn particles to 3D-networked nanostructures during battery cycling in an appropriate electrolyte. The anode steadily exhibits large capacity (∼480 mAhg-1) and energy retention capability (99.9%) during >1500 cycles even at an ultrafast charging rate of 12 690 mAg-1 (15C). The structural and chemical origins of the measured properties are explained using multiscale simulations combining molecular dynamics and density functional theory calculations. The developed method is simple, scalable, and expandable to other systems and provides an alternative robust route to obtain nanostructured anode materials in large quantities.

5.
Small ; 17(50): e2102618, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34655151

RESUMEN

Metal foil electrodes are simple to prepare and have a high active material loading, making them well suited for the fabrication of inexpensive high-energy-density batteries. Herein, Sn metal foil is used as a binder- and conductive additive-free anode for sodium-ion batteries, achieving a high reversible specific capacity of 692 mAh g-1 and coulombic efficiency of 99% after 100 cycles at a rate of 0.1 C. During the first discharge process, the anode undergoes area expansion. It then splits into multiple parts during the first-charge process. Upon cycling, the separated parts reconnect and form a single piece with a porous and robust coral structure owing to the self-healing nature of the anode. A full cell with a Sn foil anode and Na3 V2 (PO4 )3 cathode shows a stable cycle life of 100 mAh g-1 for 300 cycles. Thus, the cracking or pulverization of the Sn anode is not the principal origin of poor cycling properties. The adopted strategy will promote the development and commercialization of high-capacity metal foil anodes that undergo volume changes during charge/discharge cycling.

6.
Int J Mol Sci ; 21(22)2020 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-33207738

RESUMEN

USP7 is a promising target for the development of cancer treatments because of its high expression and the critical functions of its substrates in carcinogenesis of several different carcinomas. Here, we demonstrated the effectiveness of targeting USP7 in advanced malignant cells showing high levels of USP7, especially in taxane-resistant cancer. USP7 knockdown effectively induced cell death in several cancer cells of lung, prostate, and cervix. Depletion of USP7 induced multiple spindle pole formation in mitosis, and, consequently, resulted in mitotic catastrophe. When USP7 was blocked in the paclitaxel-resistant lung cancer NCI-H460TXR cells, which has resistance to mitotic catastrophe, NCI-H460TXR cells underwent apoptosis effectively. Furthermore, combination treatment with the mitotic kinase PLK1 inhibitor volasertib and the USP7 inhibitor P22077 showed a strong synergism through down-regulation of MDR1/ABCB1 in paclitaxel-resistant lung cancer. Therefore, we suggest USP7 is a promising target for cancer therapy, and combination therapy with inhibitors of PLK1 and USP7 may be valuable for treating paclitaxel-resistant cancers, because of their strong synergism.


Asunto(s)
Proteínas de Ciclo Celular , Resistencia a Antineoplásicos/efectos de los fármacos , Neoplasias , Paclitaxel/farmacología , Proteínas Serina-Treonina Quinasas , Proteínas Proto-Oncogénicas , Pteridinas/farmacología , Tiofenos/farmacología , Peptidasa Específica de Ubiquitina 7 , Células A549 , Proteínas de Ciclo Celular/antagonistas & inhibidores , Proteínas de Ciclo Celular/metabolismo , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/enzimología , Neoplasias/patología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/metabolismo , Peptidasa Específica de Ubiquitina 7/antagonistas & inhibidores , Peptidasa Específica de Ubiquitina 7/genética , Quinasa Tipo Polo 1
7.
J Nanosci Nanotechnol ; 18(9): 6524-6527, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-29677826

RESUMEN

A 3D sulfur cathode for a large-scale room-temperature (RT) Na/S battery with a high sulfur loading of 14.63 mg cm-2 was fabricated. The first discharge was tested in order to understand the macroscopic changes. A first discharge capacity of 865 mAh g-1 was obtained at 1/1000 C-rate along with a discharge curve with two clear plateaus at 2.29 V and 1.78 V, respectively. A visual change occurs in the 3D sulfur cathode. A thick layer of discharge products at the solid electrolyte separator face of the 3D sulfur cathode was observed and analyzed using a scanning electron microscope (SEM) coupled with energy dispersive X-ray spectroscopy (EDS).

8.
Front Plant Sci ; 14: 1155722, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37077649

RESUMEN

Anthocyanins provide blue, red, and purple color to fruits, vegetables, and flowers. Due to their benefits for human health and aesthetic appeal, anthocyanin content in crops affects consumer preference. Rapid, low-cost, and non-destructive phenotyping of anthocyanins is not well developed. Here, we introduce the normalized difference anthocyanin index (NDAI), which is based on the optical properties of anthocyanins: high absorptance in the green and low absorptance in the red part of the spectrum. NDAI is determined as (Ired - Igreen)/(Ired + Igreen), where I is the pixel intensity, a measure of reflectance. To test NDAI, leaf discs of two red lettuce (Lactuca sativa) cultivars 'Rouxai' and 'Teodore' with wide range of anthocyanin concentrations were imaged using a multispectral imaging system and the red and green images were used to calculate NDAI. NDAI and other commonly used indices for anthocyanin quantification were evaluated by comparing to with the measured anthocyanin concentration (n = 50). Statistical results showed that NDAI has advantages over other indices in terms of prediction of anthocyanin concentrations. Canopy NDAI, obtained using multispectral canopy imaging, was correlated (n = 108, R2 = 0.73) with the anthocyanin concentrations of the top canopy layer, which is visible in the images. Comparison of canopy NDAI from multispectral images and RGB images acquired using a Linux-based microcomputer with color camera, showed similar results in the prediction of anthocyanin concentration. Thus, a low-cost microcomputer with a camera can be used to build an automated phenotyping system for anthocyanin content.

9.
Theranostics ; 13(3): 1198-1216, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36793862

RESUMEN

Rationale: ß-catenin is a component for cell adhesion and a transcriptional coactivator in epithelial-mesenchymal transition (EMT). Previously we found that catalytically active PLK1 drives EMT in non-small cell lung cancer (NSCLC), upregulating extracellular matrix factors including TSG6, laminin γ2, and CD44. To understand the underlying mechanism and clinical significance of PLK1 and ß-catenin in NSCLC, their relationship and function in metastatic regulation were investigated. Methods: The clinical relevance between the survival rate of NSCLC patients and the expression of PLK1 and ß-catenin was analyzed by a KM plot. Immunoprecipitation, kinase assay, LC-MS/MS spectrometry, and site-directed mutagenesis were performed to reveal their interaction and phosphorylation. A lentiviral doxycycline-inducible system, Transwell-based 3D culture, tail-vein injection model, confocal microscopy, and chromatin immunoprecipitation assays were used to elucidate the function of phosphorylated ß-catenin in the EMT of NSCLC. Results: Clinical analysis revealed that the high expression of CTNNB1/PLK1 was inversely correlated with the survival rates of 1,292 NSCLC patients, especially in metastatic NSCLC. In TGF-ß-induced or active PLK1-driven EMT, ß-catenin, PLK1, TSG6, laminin γ2, and CD44 were concurrently upregulated. ß-catenin is a binding partner of PLK1 in TGF-ß-induced EMT and is phosphorylated at S311. Phosphomimetic ß-catenin promotes cell motility, invasiveness of NSCLC cells, and metastasis in a tail-vein injection mouse model. Its upregulated stability by phosphorylation enhances transcriptional activity through nuclear translocation for the expression of laminin γ2, CD44, and c-Jun, therefore enhancing PLK1 expression by AP-1. Conclusions: Our findings provide evidence for the critical role of the PLK1/ß-catenin/AP-1 axis in metastatic NSCLC, implying that ß-catenin and PLK1 may serve as a molecular target and prognostic indicator of the therapeutic response in metastatic NSCLC patients.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Proteínas Serina-Treonina Quinasas , beta Catenina , Animales , Ratones , beta Catenina/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Línea Celular Tumoral , Cromatografía Liquida , Matriz Extracelular/metabolismo , Laminina/metabolismo , Neoplasias Pulmonares/patología , Fosforilación , Espectrometría de Masas en Tándem , Factor de Transcripción AP-1/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Humanos , Proteínas Serina-Treonina Quinasas/metabolismo , Quinasa Tipo Polo 1
10.
J Exp Clin Cancer Res ; 42(1): 302, 2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-37968723

RESUMEN

BACKGROUND: Understanding the mechanism behind immune cell plasticity in cancer metastasis is crucial for identifying key regulators. Previously we found that mitotic factors regulate epithelial-mesenchymal transition, but how these factors convert to metastatic players in the tumor microenvironment (TME) is not fully understood. METHODS: The clinical importance of mitotic factors was analyzed by heatmap analysis, a KM plot, and immunohistochemistry in lung adenocarcinoma (LUAD) patients. Immunoprecipitation, LC-MS/MS, kinase assay, and site-directed mutagenesis were performed for the interaction and phosphorylation. A tail-vein injection mouse model, Transwell-based 3D culture, microarray analysis, coculture with monocytes, and chromatin immunoprecipitation assays were used to elucidate the function of phosphorylated FoxM1 in metastasis of TME. RESULTS: The phosphorylated FoxM1 at Ser25 by PLK1 acquires the reprogramming ability to stimulate the invasive traits in cancer and influence immune cell plasticity. This invasive form of p-FoxM1 upregulates the expression of IL1A/1B, VEGFA, and IL6 by direct activation, recruiting monocytes and promoting the polarization of M2d-like tumor-associated macrophages (TAMs). Upregulation of PD-L1 in LUAD having phosphomimetic FoxM1 facilitates immune evasion. In invasive LUAD with phosphomimetic FoxM1, IFITM1 is the most highly expressed through the activation of the STING-TBK1-IRF3 signaling, which enhances FoxM1-mediated signaling. Clinically, higher expression of FOXM1, PLK1, and IFITM1 is inversely correlated with the survival rate of advanced LUAD patients, providing a promising therapeutic strategy for the treatment of LUAD. CONCLUSION: FoxM1-based therapy would be a potential therapeutic strategy for LUAD to reduce TAM polarization, immune escape, and metastasis, since FoxM1 functions as a genetic reprogramming factor reinforcing LUAD malignancy in the TME.


Asunto(s)
Adenocarcinoma del Pulmón , Adenocarcinoma , Neoplasias Pulmonares , Animales , Ratones , Humanos , Factores de Transcripción Forkhead/metabolismo , Proteína Forkhead Box M1/genética , Macrófagos Asociados a Tumores/metabolismo , Cromatografía Liquida , Espectrometría de Masas en Tándem , Adenocarcinoma/patología , Neoplasias Pulmonares/genética , Microambiente Tumoral
11.
J Clin Invest ; 133(23)2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37815865

RESUMEN

BACKGROUNDPemphigus, a rare autoimmune bullous disease mediated by antidesmoglein autoantibodies, can be controlled with systemic medication like rituximab and high-dose systemic corticosteroids combined with immunosuppressants. However, some patients continue to experience chronically recurrent blisters in a specific area and require long-term maintenance systemic therapy.METHODSSkin with chronic blisters was obtained from patients with pemphigus. Immunologic properties of the skin were analyzed by immunofluorescence staining, bulk and single-cell RNA and TCR sequencing, and a highly multiplex imaging technique known as CO-Detection by indEXing (CODEX). Functional analyses were performed by flow cytometry and bulk RNA-Seq using peripheral blood from healthy donors. Intralesional corticosteroid was injected into patient skin, and changes in chronically recurrent blisters were observed.RESULTSWe demonstrated the presence of skin tertiary lymphoid structures (TLSs) with desmoglein-specific B cells in chronic blisters from patients with pemphigus. In the skin TLSs, CD4+ T cells predominantly produced CXCL13. These clonally expanded CXCL13+CD4+ T cells exhibited features of activated Th1-like cells and downregulated genes associated with T cell receptor-mediated signaling. Tregs are in direct contact with CXCL13+CD4+ memory T cells and increased CXCL13 production of CD4+ T cells through IL-2 consumption and TGF-ß stimulation. Finally, intralesional corticosteroid injection improved chronic blisters and reduced skin TLSs in patients with pemphigus.CONCLUSIONThrough this study we conclude that skin TLSs are associated with the persistence of chronically recurrent blisters in patients with pemphigus, and the microenvironmental network involving CXCL13+CD4+ T cells and Tregs within these structures plays an important role in CXCL13 production.TRIAL REGISTRATIONClinicalTrials.gov NCT04509570.FUNDINGThis work was supported by National Research Foundation of South Korea (NRF-2021R1C1C1007179) and Korea Drug Development Fund, which is funded by Ministry of Science and ICT; Ministry of Trade, Industry, and Energy; and Ministry of Health and Welfare (grant RS-2022-00165917).


Asunto(s)
Enfermedades Autoinmunes , Pénfigo , Humanos , Corticoesteroides , Autoanticuerpos , Enfermedades Autoinmunes/tratamiento farmacológico , Vesícula/tratamiento farmacológico , Linfocitos T CD4-Positivos , Quimiocina CXCL13 , Desmogleína 3 , Pénfigo/tratamiento farmacológico
12.
Ann Dermatol ; 34(4): 270-277, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35948329

RESUMEN

BACKGROUND: Alopecia areata (AA) is an autoimmune disease characterized by chronic inflammation, the pathogenesis of which is unknown. Stress is believed to play a role; however, evidence remains insufficient. A recent study showed that substance P (SP) damaged hair follicles by causing neurogenic inflammation, activating perifollicular mast cells, and inducing keratinocyte apoptosis. OBJECTIVE: We aimed at studying the role of SP in AA pathogenesis. We investigated the SP levels in the lesional scalp tissues and serum. We also studied the effect of SP on the inflammatory response and hair growth in the outer root sheath (ORS) cells. METHODS: We compared the serum levels of SP in 58 AA patients and 28 healthy subjects. Then, we checked the expression of SP and SP receptor, neurokinin-1 receptor (NK-1R) in the scalps of AA patients and healthy controls using immunohistochemical staining. Finally, we analyzed the mRNA expression of inflammatory cytokines and hair growth-related factors in ORS cells. RESULTS: SP and NK-1R expression were markedly higher in the hair follicles and interfollicular epidermis of the scalp lesions of AA patients. However, there was no statistically significant difference in serum SP levels between controls and patients, regardless of the type of alopecia. SP significantly increased the mRNA expression of inflammatory cytokines and decreased hair growth-related growth factors in ORS cells, but the results were not dramatic. CONCLUSION: SP triggered a localized micro-inflammation in lesional hair follicles, provoked an inflammatory response, and inhibited hair growth, thereby confirming the pathogenic role of SP in AA.

13.
Exp Mol Med ; 54(4): 414-425, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35379935

RESUMEN

Accumulating evidence indicates that mitotic protein kinases are involved in metastatic migration as well as tumorigenesis. Protein kinases and cytoskeletal proteins play a role in the efficient release of metastatic cells from a tumor mass in the tumor microenvironment, in addition to playing roles in mitosis. Mitotic protein kinases, including Polo-like kinase 1 (PLK1) and Aurora kinases, have been shown to be involved in metastasis in addition to cell proliferation and tumorigenesis, depending on the phosphorylation status and cellular context. Although the genetic programs underlying mitosis and metastasis are different, the same protein kinases and cytoskeletal proteins can participate in both mitosis and cell migration/invasion, resulting in migratory tumors. Cytoskeletal remodeling supports several cellular events, including cell division, movement, and migration. Thus, understanding the contributions of cytoskeletal proteins to the processes of cell division and metastatic motility is crucial for developing efficient therapeutic tools to treat cancer metastases. Here, we identify mitotic kinases that function in cancer metastasis as well as tumorigenesis. Several mitotic kinases, namely, PLK1, Aurora kinases, Rho-associated protein kinase 1, and integrin-linked kinase, are considered in this review, as an understanding of the shared machineries between mitosis and metastasis could be helpful for developing new strategies to treat cancer.


Asunto(s)
Neoplasias , Proteínas Quinasas , Aurora Quinasas/genética , Aurora Quinasas/metabolismo , Carcinogénesis , Proteínas de Ciclo Celular/genética , Proteínas del Citoesqueleto/metabolismo , Células HeLa , Humanos , Mitosis , Fosforilación , Proteínas Quinasas/metabolismo , Microambiente Tumoral
14.
Cell Death Differ ; 28(9): 2745-2764, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33963314

RESUMEN

The prerequisite function of vimentin for the epithelial-mesenchymal transition (EMT) is not clearly elucidated yet. Here, we show that vimentin phosphorylated by PLK1, triggers TGF-ß-signaling, which consequently leads to metastasis and PD-L1 expression for immune suppression in lung adenocarcinoma. The clinical correlation between expression of both vimentin and PLK1, and overall survival rates of patients was significant in lung adenocarcinoma but not in squamous cell carcinoma. The phosphorylation of vimentin was accompanied by the activation of PLK1 during TGF-ß-induced EMT in lung adenocarcinoma. Among the several phosphorylation sites determined by phospho-proteomic analysis and the site-specific mutagenesis, the phosphorylation at S339 displayed the most effective metastasis and tumourigenesis with the highest expression of PD-L1, compared with that of wild-type and other versions in both 3D cell culture and tail-vein injection metastasis models. Phosphomimetic vimentin at S339 interacted with p-Smad2 for its nuclear localization, leading to the expression of PD-L1. Clinical relevance revealed the inverse correlation between the survival rates of patients and the expressions of VIM, PLK1, and CD274 in primary and metastatic lung adenocarcinoma. Thus, PLK1-mediated phosphorylation of vimentin activates TGF-ß signaling pathway, leading to the metastasis and immune escape through the expression of PD-L1, functioning as a shuttling protein in lung adenocarcinoma.


Asunto(s)
Adenocarcinoma del Pulmón/genética , Antígeno B7-H1/metabolismo , Neoplasias Pulmonares/genética , Proteína Smad2/metabolismo , Escape del Tumor/genética , Vimentina/efectos adversos , Adenocarcinoma del Pulmón/patología , Animales , Humanos , Neoplasias Pulmonares/patología , Masculino , Ratones , Ratones Desnudos , Metástasis de la Neoplasia , Pronóstico , Transducción de Señal , Microambiente Tumoral
15.
Nanoscale ; 13(23): 10447-10454, 2021 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-34076016

RESUMEN

Transition-metal sulfides have been extensively studied as anode materials for use in sodium-ion batteries (SIBs) and potassium-ion batteries (PIBs) due to their multi-electron reactions, high rate performance, and abundant available resources. However, the practical capacities of metal sulfides remain low due to conductivity issues, volume expansion, and the use of traditional carbonate electrolytes. To overcome these drawbacks, ether electrolytes can be combined with nanoparticle-based metal sulfide anodes. Herein, a nanoparticle-based nickel monosulfide (NiS) anode with high rate performance in the ether electrolytes of SIBs/PIBs was prepared by heating a mixture of nickel nanoparticles with sulfur. In SIBs, the NiS anode capacity was 286 mA h g-1 at a high current density of 100 A g-1, and excellent cycling performance was observed at 25 A g-1 with a capacity of 468 mA h g-1 after 1000 cycles. Moreover, a full-cell containing a Na3V2(PO4) cathode demonstrated a rate performance of 65 mA h g-1 at a high current density of 100 A g-1. In PIBs, the NiS electrode capacity was 642 and 37 mA h g-1 at 0.5 and 100 A g-1, respectively. Hence, the synthesised NiS nanoparticles possessed excellent storage capability, regardless of the alkali-ion type, suggesting their potential use as robust NiS anodes for advanced battery systems.

16.
RSC Adv ; 11(26): 16122-16130, 2021 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-35481196

RESUMEN

Sulfurized polyacrylonitrile (SPAN) is a promising active material for Li/S batteries owing to its high sulfur utilization and long-term cyclability. However, because SPAN electrodes are synthesized using powder, they require large amounts of electrolyte, conducting agents, and binder, which reduces the practical energy density. Herein, to improve the practical energy density, we fabricated bulk-type SPAN disk cathodes from pressed sulfur and polyacrylonitrile powders using a simple heating process. The SPAN disks could be used directly as cathode materials because their π-π structures provide molecular-level electrical connectivity. In addition, the electrodes had interconnected pores, which improved the mobility of Li+ ions by allowing homogeneous adsorption of the electrolyte. The specific capacity of the optimal electrode was very high (517 mA h gelectrode -1). Furthermore, considering the weights of the anode, separator, cathode, and electrolyte, the Li/S cell exhibited a high practical energy density of 250 W h kg-1. The areal capacity was also high (8.5 mA h cm-2) owing to the high SPAN loading of 16.37 mg cm-2. After the introduction of 10 wt% multi-walled carbon nanotubes as a conducting agent, the SPAN disk electrode exhibited excellent cyclability while maintaining a high energy density. This strategy offers a potential candidate for Li/S batteries with high practical energy densities.

17.
Ann Dermatol ; 33(6): 541-548, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34858005

RESUMEN

BACKGROUND: Sebocytes are the main cells involved in the pathogenesis of acne by producing lipids and inflammatory cytokines. Although palmitic acid (PA) has been suggested to induce an inflammatory reaction, its effect on sebocytes remains to be elucidated. OBJECTIVE: In the present study, we investigated whether PA promotes inflammasome-mediated inflammation of sebocytes both in vivo and in vitro. METHODS: We intradermally injected PA into the mice ears. And, we treated cultured human sebocytes with PA. Inflammasome-mediated inflammation was verified by immunohistochemistry, Western blot and ELISA. RESULTS: PA-treated mice developed an inflammatory response associated with increased interleukin (IL)-1ß expression in the sebaceous glands. When PA was added to cultured human sebocytes, caspase-1 activation and IL-1ß secretion were significantly enhanced. In addition, NLRP3 knockdown attenuated IL-1ß production by sebocytes stimulated with PA. PA-mediated inflammasome activation required reactive oxygen species. CONCLUSION: These findings indicate that PA activates the NLRP3 inflammasome before induction of an inflammatory response in sebocytes. Thus, PA may play a role in the inflammation of acne.

18.
J Nanosci Nanotechnol ; 20(11): 7092-7095, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-32604563

RESUMEN

A polyacrylonitrile (PAN) nanofiber web was prepared by electrospinning PAN solutions with dimethyl sulfoxide (DMSO) or Dimethylformamide (DMF) as solvent. The PAN web was heated with sulfur to synthesize a sulfurized polyacrylonitrile (SPAN) nanofiber web. The shape of the SPAN web was found to depend on concentration of the PAN solution and properties of the solvent. The SPAN web synthesized using 8 wt% PAN solution in DMSO showed the highest capacity of 1053.3 mAh g-1sulfur under a current density of 526 mA g-1sulfur. Thus, we determined that DMSO could be a potential solvent for preparation of SPAN web electrodes.

19.
Nanoscale Adv ; 2(11): 5166-5170, 2020 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-36132030

RESUMEN

Sodium-ion batteries (SIBs) are a viable substitute for lithium-ion batteries due to the low cost and wide availability of sodium. However, practical applications require the development of fast charging sodium-ion-based full-cells with high power densities. Na3V2(PO4)3 (NVP) is a bipolar material with excellent characteristics as both a cathode and an anode material in SIBs. Designing symmetric cells with NVP results in a single voltage plateau with significant specific capacity which is ideal for a full cell. Here we demonstrate for the first time a tremendous improvement in the performance of NVP symmetric full cells by introducing an ether-based electrolyte which favors fast reaction kinetics. In a symmetric full cell configuration, 75.5% of the initial capacity was retained even after 4000 cycles at 2 A g-1, revealing ultra-long cyclability. Excellent rate performances were obtained at current densities as high as 1000C, based on the cathode mass, revealing ultrafast Na+ transfer. The power density obtained for this NVP symmetric cell (48 250 W kg-1) is the best among those of all the sodium-ion-based full cells reported to date.

20.
J Nanosci Nanotechnol ; 20(11): 7119-7123, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-32604568

RESUMEN

Owing to the speculated price hike and scarcity of lithium resources, sodium-ion batteries are attracting significant research interest these days. However, sodium-ion battery anodes do not deliver good electrochemical performance, particularly rate performance. Herein, we report the facile electrospinning synthesis of a free-standing nickel disulfide (NiS²) embedded on carbon nanofiber. This electrode did not require a conducting agent, current collector, and binder, and typically delivered high capacity and rate performance. The electrode delivered a high initial capacity of 603 mAh g-1 at the current density of 500 mA g-1. Moreover, the electrode delivered the capacity of 271 mAh g-1 at the high current density of 15 A g-1. The excellent rate performance and high coulombic efficiency of the electrode were attributed to its low charge transfer resistance and unique structure.

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