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2.
Ocul Immunol Inflamm ; : 1-11, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709230

RESUMO

PURPOSE: We aimed to evaluate adalimumab efficacy in patients with initial-onset or recurrent Vogt-Koyanagi-Harada (VKH) syndrome. METHODS: A retrospective clinical study was performed to examine the therapeutic effect of adalimumab in 22 VKH patients,16 with initial-onset and six with recurrent VKH. Another 22 patients with initial-onset VKH who did not receive adalimumab were included as controls. The main observational parameters included the central macular thickness (CMT), subfoveal choroidal thickness (SCT), best-corrected visual acuity (BCVA), anterior chamber cell grade (ACC), glucocorticoid dose (GCD), and the development of sunset glow fundus. MRNA sequencing was used to profile the tumor necrosis factor (TNF)-α pathway in peripheral blood mononuclear cells obtained from nine patients with initial-onset VKH disease, six patients with recurrent VKH, and eight healthy controls. RESULTS: In the initial-onset group, adalimumab therapy significantly improved the BCVA, CMT, SCT, and ACC. Furthermore, adalimumab significantly decreased GCD in patients with initial-onset. In patients with recurrent VKH, the SCT significantly improved after adalimumab treatment, but no significant changes in BCVA, CMT, and ACC were observed. All six patients experienced relapse during follow-up. The TNF-α pathway exhibited a significant increase in initial-onset VKH when compared with that in both healthy controls and recurrent patients. Conversely, it was suppressed in recurrent VKH when compared with that in the initial-onset or healthy control groups. CONCLUSIONS: In patients with initial-onset VKH, adalimumab effectively reduces glucocorticoid dependence. However, adalimumab may not be effective for preventing relapse or providing long-term inflammation relief in patients with recurrent VKH.

3.
Appl Opt ; 63(7): 1867-1874, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38437291

RESUMO

Extreme ultraviolet (EUV) radiation plays a key role in the fields of material science, attosecond metrology, and lithography. However, the reflective optical components typically used in EUV systems contribute to their bulky size, weight, and increased costs for fabrication. In this paper, we theoretically investigate transmissive metalens designs capable of focusing the EUV light based on the Pancharatnam-Berry phase. The designed metalens is composed of nanoscale elliptical holes, which can guide and manipulate EUV light due to the higher refractive index of the vacuum holes compared to that of the surrounding material. We designed an EUV metalens with a diameter of 10 µm, which supports a focal length of 24 µm and a numerical aperture of up to 0.2. It can focus 55-nm EUV incident light to a diffraction-limited spot, and the focusing efficiency is calculated to be as high as about 7% over a broad EUV frequency range (50-65 nm). This study reveals the possibility of applying a dielectric metalens in the EUV region without a transmissive optical material.

4.
Genomics ; 116(2): 110819, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38432498

RESUMO

Long noncoding RNA (lncRNA) and microRNA (miRNA) are known to play pivotal roles in mammalian testicular function and spermatogenesis. However, their impact on porcine male reproduction has yet to be well unraveled. Here, we sequenced and identified lncRNA and miRNA expressed in the testes of Chinese indigenous Banna mini-pig inbred line (BMI) and introduced Western Duroc (DU) and Large White (LW) pigs. By pairwise comparison (BMI vs DU, BMI vs LW, and DU vs LW), we found the gene expression differences in the testes between Chinese local pigs and introduced Western commercial breeds were more striking than those between introduced commercial breeds. Furthermore, we found 1622 co-differentially expressed genes (co-DEGs), 122 co-differentially expressed lncRNAs (co-DELs), 39 co-differentially expressed miRNAs (co-DEMs) in BMI vs introduced commercial breeds (DU and LW). Functional analysis revealed that these co-DEGs and co-DELs/co-DEMs target genes were enriched in male sexual function pathways, including MAPK, AMPK, TGF-ß/Smad, Hippo, NF-kappa B, and PI3K/Akt signaling pathways. Additionally, we established 10,536 lncRNA-mRNA, 11,248 miRNA-mRNA pairs, and 62 ceRNA (lncRNA-miRNA-mRNA) networks. The ssc-miR-1343 had the most interactive factors in the ceRNA network, including 20 mRNAs and 3 lncRNAs, consisting of 56 ceRNA pairs. These factors played extremely important roles in the regulation of testis function as key nodes in the interactive regulatory network. Our results provide insight into the functional roles of lncRNAs and miRNAs in porcine testis and offer a valuable resource for understanding the differences between Chinese indigenous and introduced Western pigs.


Assuntos
MicroRNAs , RNA Longo não Codificante , Masculino , Suínos/genética , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Fosfatidilinositol 3-Quinases/genética , Testículo/metabolismo , Porco Miniatura/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Redes Reguladoras de Genes
5.
BMC Public Health ; 24(1): 445, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38347466

RESUMO

BACKGROUND: Subjective well-being (SWB) plays an essential role in general health. Although beneficial effects of selected micronutrients and foods on SWB have been reported, they do not reflect the impact of the habitual diet on SWB. Therefore, the purpose of this study is to investigate the association between adherence to the Chinese Dietary Guidelines (CDG) with SWB. METHODS: This study combined a cross-sectional survey and a daily diary investigation. The cross-sectional survey was conducted on 1,433 students from 8 universities in southern China between October and November 2020. The daily diary investigation was conducted in November 2022, collecting 10-day daily data from 115 students at two universities in southern China over ten consecutive days, resulting in 1,020 valid matched daily responses. Adherence to the CDG was assessed by the China Prime Diet Quality Score (CPDQS), SWB was measured by the Index of Well-being (IWB) and the Affect Valuation Index (AVI). Correlation analysis, multiple regression analyses, and hierarchical regression were conducted to examine the associations of adherence to the CDG with its components, and SWB. RESULTS: The cross-sectional survey revealed significant predictors of SWB, including adherence to the CDG (ß = 0.24, p<0.001) and its components: cereals and tubers (ß = 0.07, p = 0.024), vegetables and fruits (ß = 0.11, p<0.001), dairy/soy/nuts (ß = 0.11, p = 0.002), and condiments and alcoholic beverages (ß = 0.08, p = 0.002). The daily diary investigation showed positive associations between adherence to the CDG (ß = 0.19, p<0.001), and its components: vegetables and fruits (ß = 0.11, p = 0.001), dairy/soy/nuts (ß = 0.06, p = 0.009), animal source food (ß = 0.06, p = 0.026), and condiments and alcoholic beverages (ß = 0.07, p = 0.026), with higher levels of daily SWB. CONCLUSIONS: Adherence to healthy dietary patterns such as the CDG, rather than focusing on individual components in isolation, is associated with better SWB. Furthermore, the consumption of CDG components had an impact on SWB, although the specific effects varied between the two studies. This study offers modest evidence supporting the role of the CDG in promoting positive mental health.


Assuntos
Dieta , Verduras , Animais , Humanos , Estudos Transversais , Frutas , Política Nutricional , China
6.
Sci Data ; 10(1): 678, 2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37798273

RESUMO

The production of semen in boars involves multiple reproductive glands, including the testis (Tes), epididymis (Epi), vesicular gland (VG), prostate gland (PG), and bulbourethral gland (BG). However, previous studies on boar reproduction primarily focused on the testis, with little attention paid to the other glands. Here, we integrated single-molecule long-read sequencing with short-read sequencing to characterize the RNA landscape from five glands of Banna mini-pig inbred line (BMI) and Diannan small-ear pigs (DSE). We identified 110,996 full-length isoforms from 22,298 genes, and classified the alternative splicing (AS) events in these five glands. Transcriptome-wide variation analysis indicated that the number of single nucleotide polymorphisms (SNPs) in five tissues of BMI was significantly lower than that in the non-inbred pig, DSE, revealing the effect of inbreeding on BMI. Additionally, we performed small-RNA sequencing and identified 299 novel miRNAs across all glands. Overall, our findings provide a comprehensive overview of the RNA landscape within these five glands, paving the path for future investigations on reproductive biology and the impact of inbreeding on pig transcriptome.


Assuntos
Processamento Alternativo , MicroRNAs , Suínos , Testículo , Animais , Masculino , Genitália , Análise de Sequência de RNA , Suínos/genética , Porco Miniatura , Testículo/metabolismo , Transcriptoma , Polimorfismo de Nucleotídeo Único
7.
Commun Biol ; 6(1): 911, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37670137

RESUMO

The immune synapse, a highly organized structure formed at the interface between T lymphocytes and antigen-presenting cells (APCs), is essential for T cell activation and the adaptive immune response. It has been shown that this interface shares similarities with the primary cilium, a sensory organelle in eukaryotic cells, although the roles of ciliary proteins on the immune synapse remain elusive. Here, we find that inositol polyphosphate-5-phosphatase E (INPP5E), a cilium-enriched protein responsible for regulating phosphoinositide localization, is enriched at the immune synapse in Jurkat T-cells during superantigen-mediated conjugation or antibody-mediated crosslinking of TCR complexes, and forms a complex with CD3ζ, ZAP-70, and Lck. Silencing INPP5E in Jurkat T-cells impairs the polarized distribution of CD3ζ at the immune synapse and correlates with a failure of PI(4,5)P2 clearance at the center of the synapse. Moreover, INPP5E silencing decreases proximal TCR signaling, including phosphorylation of CD3ζ and ZAP-70, and ultimately attenuates IL-2 secretion. Our results suggest that INPP5E is a new player in phosphoinositide manipulation at the synapse, controlling the TCR signaling cascade.


Assuntos
Anticorpos , Monoéster Fosfórico Hidrolases , Fosfatidilinositóis , Receptores de Antígenos de Linfócitos T
8.
Appl Opt ; 62(26): 7111-7118, 2023 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-37707053

RESUMO

Quantum dot solar cells (QDSCs) are regarded as one of the most efficient devices due to their intermediate band structures. A suitable light-trapping (LT) strategy matching the absorption spectrum is important to improve the photocurrent conversion efficiency of QDSCs. In this paper, we have proposed a design of the periodically patterned top and bottom dielectric nanopyramid arrays for highly efficient light trapping in GaAs-based QDSCs. The dielectric nanopyramid arrays significantly improve the light absorption of QDSCs in the longer wavelength between 0.8 µm and 1.2 µm. In addition, this LT structure ensures a completely flat window layer and back surface field layer while passivating these semiconductor surfaces. For the optimized double-sided structure, the short-circuit current generated by QDSC is 34.32m A/c m 2, where the photocurrent from the quantum dots (QDs) is 5.17m A/c m 2. Compared to the photocurrent of the QDSC without an LT structure, the photocurrent of the double-sided structure is increased by 84%. The QD photocurrent of the double-sided structure is increased by 570% compared to that of the QDSC without the LT structure.

9.
Invest Ophthalmol Vis Sci ; 64(12): 11, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37672286

RESUMO

Purpose: Circulating exosomes regulate immune responses and induce immune tolerance in immune-mediated diseases. This study aimed to investigate the role of circulating small extracellular vesicles (sEVs) derived from patients with Vogt-Koyanagi-Harada (VKH) syndrome, in T-cell responses. Methods: The sEVs were isolated from the plasma of healthy controls, patients with VKH, and other uveitis patients. The effects of autologous and allogeneic sEVs on the proliferation of circulating CD4+ T cells were evaluated. Microarray analysis of sEVs was performed to determine their differential miRNA expression profiles. The target genes of the candidate miRNA were predicted and verified. The role of both the candidate miRNA and target genes in T-cell proliferation was tested. Results: Plasma-derived sEVs from patients with VKH inhibited the proliferation of autologous CD4+ T cells. Among all the miRNAs that might be associated with inflammatory activity, we found that miR-410-3p had the largest number of T-cell proliferation target genes. MiR-410-3p mimics inhibited the proliferation of Jurkat cells and CD4+ T cells. C-X-C motif chemokine ligand 5 (CXCL5) was confirmed to be a potential target gene of miR-410-3p, and siRNA-mediated CXCL5 knockdown inhibited cell proliferation. Conclusions: Circulating sEVs exert an inhibitory effect on autologous CD4+ T cells mediated by miR-410-3p by targeting CXCL5, supporting the possibility of using autogenic sEVs to inhibit ocular inflammation.


Assuntos
Exossomos , Vesículas Extracelulares , MicroRNAs , Síndrome Uveomeningoencefálica , Humanos , Ativação Linfocitária , Proliferação de Células , Quimiocina CXCL5
10.
Redox Biol ; 65: 102836, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37541055

RESUMO

Photoreceptors (PRs) degeneration is central to visual impairment and loss in most blind retinal diseases, including age-related macular disease (AMD) and diabetic retinopathy (DR). PRs are susceptible to oxidative stress owing to their unique metabolic features. Accumulating evidence has demonstrated that the targeting oxidative stress is a promising treatment strategy for PR degeneration. Herein, we introduced potent antioxidative platinum nanoparticles (Pt NPs) to treat PRs degeneration in this study. The Pt NPs exhibited multi-enzymatic antioxidant activity and protected PRs from H2O2-induced oxidative damage in vitro assays. Based on the same mechanism, the intravitreal injection of Pt NPs significantly reduced cell apoptosis, maintained retinal structure and preserved retinal function in a mouse model of light-induced retinal degeneration (LIRD). Most importantly, the results of RNA sequencing showed that the transcription of antioxidative genes was upregulated, and metabolic reprogramming occurred in the LIRD-retina after treatment with Pt NPs, both of which benefited retinal survival from oxidative damage. The results indicated that Pt NPs were indeed potent therapeutic candidates for PRs degeneration in blind retinal diseases.


Assuntos
Nanopartículas Metálicas , Degeneração Retiniana , Camundongos , Animais , Degeneração Retiniana/tratamento farmacológico , Degeneração Retiniana/etiologia , Degeneração Retiniana/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Platina/farmacologia , Peróxido de Hidrogênio , Estresse Oxidativo , Modelos Animais de Doenças
11.
Exp Eye Res ; 234: 109572, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37451566

RESUMO

Our previous research shown that tumor necrosis factor-alpha-induced protein 8 (TNFAIP8) is elevated in the plasma extracellular vesicles and vitreous humor in diabetic retinopathy (DR). TNFAIP8 also significantly increases the viability of human retinal microvascular endothelial cells (HRMECs) and promotes cell migration and tube formation in vitro. To comprehensively explore its role in DR, we investigated the effect of TNFAIP8 on DR development using an animal model in this study. A TNFAIP8-overexpressing adeno-associated virus (AAV) vector and streptozotocin-induced mouse model was used. The AAV-TNFAIP8 vector was injected into the mice intravitreally, and the effect was evaluated. The evaluation included analysis of retinal structure and function using electroretinography, optical coherence tomography, and histological assessment. The influence of TNFAIP8 on the avascular area, retinal leukostasis, and the expression levels of inflammatory factors was also determined. TNFAIP8 significantly decreased a/b-wave amplitude and retinal thickness in diabetic mice. Histological assessment showed that TNFAIP8 aggravated pathological abnormalities with distorted organization of the retina. TNFAIP8 also significantly increased the avascular area, leukostasis, and the expression of inflammatory factors, such as TNFα, IL1ß, ICAM1, and GFAP, in the retina. The results of this study support the role of TNFAIP8 in DR pathogenesis. A mechanistic understanding of TNFAIP8 may offer novel therapeutic strategies.


Assuntos
Diabetes Mellitus Experimental , Retinopatia Diabética , Leucostasia , Camundongos , Humanos , Animais , Retinopatia Diabética/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Diabetes Mellitus Experimental/metabolismo , Fator VIII/metabolismo , Fator VIII/farmacologia , Fator VIII/uso terapêutico , Células Endoteliais/metabolismo , Leucostasia/metabolismo , Retina/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo
12.
Discov Nano ; 18(1): 67, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37382764

RESUMO

Quantum dot intermediate band solar cell (QD-IBSC) has high efficiency theoretically. It can absorb photons with energy lower than the bandgap of the semiconductor through the half-filled intermediate band, extending the absorption spectrum of the cell. However, issues in the IBSC, such as the strain around multi-stacking QDs, low thermal excitation energy, and short carrier lifetime, lead to its low conversion efficiency. In recent years, many efforts have been made from different aspects. In this paper, we focus on In(Ga)As QD-IBSC, list the experimental technologies used to improve the performance of the cell and review the recent research progress. By analyzing the effects of different technologies on conversion efficiency, the development direction of the In(Ga)As QD-IBSC in the future is proposed.

13.
J Transl Med ; 21(1): 388, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37322475

RESUMO

BACKGROUND: Uveitis and posterior scleritis are sight-threatening diseases with undefined pathogenesis and accurate diagnosis remains challenging. METHODS: Two plasma-derived extracellular vesicle (EV) subpopulations, small and large EVs, obtained from patients with ankylosing spondylitis-related uveitis, Behcet's disease uveitis, Vogt-Koyanagi-Harada syndrome, and posterior scleritis were subjected to proteomics analysis alongside plasma using SWATH-MS. A comprehensive bioinformatics analysis was performed on the proteomic profiles of sEVs, lEVs, and plasma. Candidate biomarkers were validated in a new cohort using ELISA. Pearson correlation analysis was performed to analyze the relationship between clinical parameters and proteomic data. Connectivity map database was used to predict therapeutic agents. RESULTS: In total, 3,668 proteins were identified and over 3000 proteins were quantified from 278 samples. When comparing diseased group to healthy control, the proteomic profiles of the two EV subgroups were more correlated with disease than plasma. Comprehensive bioinformatics analysis highlighted potential pathogenic mechanisms for these diseases. Potential biomarker panels for four diseases were identified and validated. We found a negative correlation between plasma endothelin-converting enzyme 1 level and mean retinal thickness. Potential therapeutic drugs were proposed, and their targets were identified. CONCLUSIONS: This study provides a proteomic landscape of plasma and EVs involved in ankylosing spondylitis-related uveitis, Behcet's disease uveitis, Vogt-Koyanagi-Harada syndrome, and posterior scleritis, offers insights into disease pathogenesis, identifies valuable biomarker candidates, and proposes promising therapeutic agents.


Assuntos
Síndrome de Behçet , Vesículas Extracelulares , Esclerite , Espondilite Anquilosante , Uveíte , Síndrome Uveomeningoencefálica , Humanos , Síndrome de Behçet/diagnóstico , Síndrome de Behçet/complicações , Síndrome Uveomeningoencefálica/diagnóstico , Síndrome Uveomeningoencefálica/complicações , Esclerite/etiologia , Espondilite Anquilosante/complicações , Proteômica , Uveíte/complicações
14.
Sci Rep ; 13(1): 7511, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37161032

RESUMO

We investigated the growth and evolution of Si-based Ge quantum dots (Ge/Si QDs) under low Ge deposition (1.2-4.4 nm thick) using magnetron sputtering. The morphology and structure of QDs were analyzed with the help of an atomic force microscope (AFM), scanning electron microscope, transmission electron microscope, Raman, surface energy theory and dynamics theory, the photoelectric properties of QDs were characterized by photoluminescence (PL) spectra. The results showed that the growth mechanism of QDs conformed to Stranski-Krastanow mode, but the typical thickness of the wetting layer was nearly three times higher than those derived from conventional technologies such as molecular beam epitaxy, chemical vapor deposition, solid phase epitaxy and so on. Meanwhile, the shape evolution of QDs was very different from existing reports. The specific internal causes of these novel phenomena were analyzed and confirmed and reported in this paper. In addition, the AFM, Raman, and PL tests all indicated that the QDs grown when 3.4 nm Ge was deposited have the most excellent morphology, structure, and optoelectronic performance. Our work lays a foundation for further exploration of the controllable growth of QDs at high deposition rates, which is a new way to realize the industrialization of QDs used for future devices.

15.
Sensors (Basel) ; 23(8)2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37112146

RESUMO

This work presents a silicon-based capacitively transduced width extensional mode (WEM) MEMS rectangular plate resonator with quality factor (Q) of over 10,000 at a frequency of greater than 1 GHz. The Q value, determined by various loss mechanisms, was analyzed and quantified via numerical calculation and simulation. The energy loss of high order WEMs is dominated by anchor loss and phonon-phonon interaction dissipation (PPID). High-order resonators possess high effective stiffness, resulting in large motional impedance. To suppress anchor loss and reduce motional impedance, a novel combined tether was designed and comprehensively optimized. The resonators were batch fabricated based on a reliable and simple silicon-on-insulator (SOI)-based fabrication process. The combined tether experimentally contributes to low anchor loss and motional impedance. Especially in the 4th WEM, the resonator with a resonance frequency of 1.1 GHz and a Q of 10,920 was demonstrated, corresponding to the promising f × Q product of 1.2 × 1013. By using combined tether, the motional impedance decreases by 33% and 20% in 3rd and 4th modes, respectively. The WEM resonator proposed in this work has potential application for high-frequency wireless communication systems.

16.
Angew Chem Int Ed Engl ; 62(21): e202303011, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36949029

RESUMO

Aqueous Zn-Iodine (I2 ) batteries are attractive for large-scale energy storage. However, drawbacks include, Zn dendrites, hydrogen evolution reaction (HER), corrosion and, cathode "shuttle" of polyiodines. Here we report a class of N-containing heterocyclic compounds as organic pH buffers to obviate these. We evidence that addition of pyridine /imidazole regulates electrolyte pH, and inhibits HER and anode corrosion. In addition, pyridine and imidazole preferentially absorb on Zn metal, regulating non-dendritic Zn plating /stripping, and achieving a high Coulombic efficiency of 99.6 % and long-term cycling stability of 3200 h at 2 mA cm-2 , 2 mAh cm-2 . It is also confirmed that pyridine inhibits polyiodines shuttling and boosts conversion kinetics for I- /I2 . As a result, the Zn-I2 full battery exhibits long cycle stability of >25 000 cycles and high specific capacity of 105.5 mAh g-1 at 10 A g-1 . We conclude organic pH buffer engineering is practical for dendrite-free and shuttle-free Zn-I2 batteries.

17.
Materials (Basel) ; 16(4)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36837328

RESUMO

Geopolymeric recycled concrete (GRC) is a new low-carbon building material that uses both construction and industrial solid waste to replace natural aggregate and cement. GRC is similar to geopolymeric concrete (GPC) in that it has good mechanical properties but needs to be improved in terms of frost resistance. Previous studies have shown that polyoxymethylene fiber (POM fiber) can improve the shrinkage and durability of concrete and is superior to other commonly used fibers. Therefore, this paper explores adding POM fiber to GRC to improve its frost resistance. In this paper, the influence of different volumes and lengths of POM fiber on the frost resistance of geopolymeric recycled concrete (PRGRC) is studied. By measuring the changes in mass loss rate, relative dynamic elastic modulus, and compressive strength of PRGRC under different cycles, the improvement effect of POM fiber on the freeze-thaw damage of GRC is analyzed, and the strength attenuation model of PRGRC is established. The results show that the increase in POM fiber content can effectively slow down the mass loss of PRGRC in the freeze-thaw cycles, the reduction rate of relative dynamic elastic modulus, and the reduction rate of compressive strength. This shows that POM fiber can effectively improve the frost resistance of PRGRC, and the effect of 6 mm POM fiber on the freeze-thaw damage of PRGRC is better than 12 mm POM fiber. According to the test results, the existing strength attenuation model is further modified, the attenuation model of PRGRC compressive strength under the freeze-thaw cycle is obtained, and the model fitting effect is good. The strengthening mechanism of POM fiber is explained by the structural relationship between POM fiber and concrete matrix in the SEM micrograph of PRGRC. The research results provide a scientific basis for the applicability of POM fiber in geopolymeric cementitious materials and improving the frost resistance of PRGRC.

18.
Micromachines (Basel) ; 14(2)2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36838006

RESUMO

The silicon etching process is a core component of production in the semiconductor industry. Undercut is a nonideal effect in silicon dry etching. A reduced undercut is desired when preparing structures that demand a good sidewall morphology, while an enlarged undercut is conducive to the fabrication of microstructure tips. Undercut is related to not only the production parameters but also the mask materials. In this study, five mask materials-Cr, Al, ITO, SiNx, and SiO2-are chosen to compare the undercut effect caused by the isotropic etching process and the Bosch process. In the Bosch process, the SiNx mask causes the largest undercut, and the SiO2 mask causes the smallest undercut. In the isotropic process, the results are reversed. The effect of charges in the mask layer is found to produce this result, and the effect of electrons accumulating during the process is found to be negligible. The undercut effect can be enhanced or suppressed by selecting appropriate mask materials, which is helpful in the MEMS process. Finally, using an Al mask, a tapered silicon tip with a top diameter of 119.3 nm is fabricated using the isotropic etching process.

19.
Sensors (Basel) ; 23(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36679382

RESUMO

Over 70% of the earth's surface is covered by oceans; globally, oceans provides a huge source of wealth to humans. In the literature, several sensors have been developed to investigate oceans. Electrical conductivity temperature depth (CTD) sensors were used frequently and extensively. Long-term accurate CTD data is important for the study and utilization of oceans, e.g., for weather forecasting, ecological evolution, fishery, and shipping. Several kinds of CTD sensors based on electrics, optical, acoustic wave and radio waves have been developed. CTD sensors are often utilized by measuring electrical signals. The latest progress of CTD sensors will be presented in order of performance. The principles, structure, materials and properties of many CTD sensors were discussed in detail. The commercially available CTD sensors were involved and their respective performances were compared. Some possible development directions of CTD sensors for ocean investigation are proposed.


Assuntos
Eletricidade , Tempo (Meteorologia) , Humanos , Condutividade Elétrica , Oceanos e Mares
20.
Angew Chem Int Ed Engl ; 62(4): e202215600, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36446737

RESUMO

Zinc metal battery (ZMB) is promising as the next generation of energy storage system, but challenges relating to dendrites and corrosion of the zinc anode are restricting its practical application. Here, to stabilize Zn anode, we report a controlled electrolytic method for a monolithic solid-electrolyte interphase (SEI) via a high dipole moment solvent dimethyl methylphosphonate (DMMP). The DMMP-based electrolytes can generate a homogeneous and robust phosphate SEI (Zn3 (PO4 )2 and ZnP2 O6 ). Benefiting from the protecting impact of this in situ monolithic SEI, the zinc electrode exhibits long-term cycling of 4700 h and a high Coulombic efficiency 99.89 % in Zn|Zn and Zn|Cu cell, respectively. The full V2 O5 |Zn battery with DMMP-H2 O hybrid electrolyte exhibits a high capacity retention of 82.2 % following 4000 cycles under 5 A g-1 . The first success in constructing the monolithic phosphate SEI will open a new avenue in electrolyte design for highly reversible and stable Zn metal anodes.

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