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15 pages, 3251 KiB  
Article
Eugenol: A Potential Modulator of Human Platelet Activation and Mouse Mesenteric Vascular Thrombosis via an Innovative cPLA2-NF-κB Signaling Axis
by Yi Chang, Chih-Wei Hsia, Kuan-Rau Chiou, Ting-Lin Yen, Thanasekaran Jayakumar, Joen-Rong Sheu and Wei-Chieh Huang
Biomedicines 2024, 12(8), 1689; https://doi.org/10.3390/biomedicines12081689 - 29 Jul 2024
Viewed by 482
Abstract
Background: Platelets, a type of anucleated cell, play a crucial role in cardiovascular diseases (CVDs). Therefore, targeting platelet activation is essential for mitigating CVDs. Endogenous agonists, such as collagen, activate platelets by initiating signal transduction through specific platelet receptors, leading to platelet aggregation. [...] Read more.
Background: Platelets, a type of anucleated cell, play a crucial role in cardiovascular diseases (CVDs). Therefore, targeting platelet activation is essential for mitigating CVDs. Endogenous agonists, such as collagen, activate platelets by initiating signal transduction through specific platelet receptors, leading to platelet aggregation. Eugenol, primarily sourced from clove oil, is known for its antibacterial, anticancer, and anti-inflammatory properties, making it a valuable medicinal agent. In our previous study, eugenol was shown to inhibit platelet aggregation induced by collagen and arachidonic acid. We concluded that eugenol exerts a potent inhibitory effect on platelet activation by targeting the PLCγ2–PKC and cPLA2-TxA2 pathways, thereby suppressing platelet aggregation. In our current study, we found that eugenol significantly inhibits NF-κB activation. This led us to investigate the relationship between the NF-κB and cPLA2 pathways to elucidate how eugenol suppresses platelet activation. Methods: In this study, we prepared platelet suspensions from the blood of healthy human donors to evaluate the inhibitory mechanisms of eugenol on platelet activation. We utilized immunoblotting and confocal microscopy to analyze these mechanisms in detail. Additionally, we assessed the anti-thrombotic effect of eugenol by observing fluorescein-induced platelet plug formation in the mesenteric microvessels of mice. Results: For immunoblotting and confocal microscopy studies, eugenol significantly inhibited NF-κB-mediated signaling events stimulated by collagen in human platelets. Specifically, it reduced the phosphorylation of IKK and p65 and prevented the degradation of IκBα. Additionally, CAY10502, a cPLA2 inhibitor, significantly reduced NF-κB-mediated signaling events. In contrast, BAY11-7082, an IKK inhibitor, did not affect collagen-stimulated cPLA2 phosphorylation. These findings suggest that cPLA2 acts as an upstream regulator of NF-κB activation during platelet activation. Furthermore, both BAY11-7082 and CAY10502 significantly reduced the collagen-induced rise in intracellular calcium levels. In the animal study, eugenol demonstrated potential as an anti-thrombotic agent by significantly reducing platelet plug formation in fluorescein-irradiated mouse mesenteric microvessels. Conclusion: Our study uncovered a novel pathway in platelet activation involving the cPLA2-NF-κB axis, which plays a key role in the antiplatelet effects of eugenol. These findings suggest that eugenol could serve as a valuable and potent prophylactic or therapeutic option for arterial thrombosis. Full article
(This article belongs to the Special Issue Bioactive Compounds in Chronic Diseases—2nd Edition)
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12 pages, 451 KiB  
Article
CNV Analysis through Exome Sequencing Reveals a Large Duplication Involved in Sex Reversal, Neurodevelopmental Delay, Epilepsy and Optic Atrophy
by Cybel Mehawej, Joy El Maalouf, Mohamad Abdelkhalik, Peter Mahfouz, Eliane Chouery and Andre Megarbane
Genes 2024, 15(7), 901; https://doi.org/10.3390/genes15070901 - 10 Jul 2024
Viewed by 697
Abstract
Background: Duplications on the short arm of chromosome X, including the gene NR0B1, have been associated with gonadal dysgenesis and with male to female sex reversal. Additional clinical manifestations can be observed in the affected patients, depending on the duplicated genomic region. [...] Read more.
Background: Duplications on the short arm of chromosome X, including the gene NR0B1, have been associated with gonadal dysgenesis and with male to female sex reversal. Additional clinical manifestations can be observed in the affected patients, depending on the duplicated genomic region. Here we report one of the largest duplications on chromosome X, in a Lebanese patient, and we provide the first comprehensive review of duplications in this genomic region. Case Presentation: A 2-year-old female patient born to non-consanguineous Lebanese parents, with a family history of one miscarriage, is included in this study. The patient presents with sex reversal, dysmorphic features, optic atrophy, epilepsy, psychomotor and neurodevelopmental delay. Single nucleotide variants and copy number variants analysis were carried out on the patient through exome sequencing (ES). This showed an increased coverage of a genomic region of around 23.6 Mb on chromosome Xp22.31-p21.2 (g.7137718-30739112) in the patient, suggestive of a large duplication encompassing more than 60 genes, including the NR0B1 gene involved in sex reversal. A karyotype analysis confirmed sex reversal in the proband presenting with the duplication, and revealed a balanced translocation between the short arms of chromosomes X and 14:46, X, t(X;14) (p11;p11) in her/his mother. Conclusions: This case highlights the added value of CNV analysis from ES data in the genetic diagnosis of patients. It also underscores the challenges encountered in announcing unsolicited incidental findings to the family. Full article
(This article belongs to the Section Human Genomics and Genetic Diseases)
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20 pages, 2118 KiB  
Communication
Preliminary Study on the Restoration of the Phospholipid Profile in Serum from Patients with COVID-19 by Treatment with Vitamin E
by María Elena Soto, Linaloe Manzano-Pech, Verónica Guarner-Lans, Adrían Palacios-Chavarría, Rafael Ricardo Valdez-Vázquez, Raúl Martínez-Memije, Mohammed El-Hafidi, Félix Leao Rodríguez-Fierros and Israel Pérez-Torres
Curr. Issues Mol. Biol. 2024, 46(7), 7219-7238; https://doi.org/10.3390/cimb46070429 - 8 Jul 2024
Viewed by 817
Abstract
SARS-CoV-2 is an obligatory intracellular pathogen that requires a lipid bilayer membrane for its transport to build its nucleocapsid envelope and fuse with the host cell. The biological membranes are constituted by phospholipids (PLs), and vitamin E (Vit E) protects them from oxidative [...] Read more.
SARS-CoV-2 is an obligatory intracellular pathogen that requires a lipid bilayer membrane for its transport to build its nucleocapsid envelope and fuse with the host cell. The biological membranes are constituted by phospholipids (PLs), and vitamin E (Vit E) protects them from oxidative stress (OS). The aim of this study was to demonstrate if treatment with Vit E restores the modified profile of the FA in PLs in serum from patients with coronavirus disease-19 (COVID-19). We evaluated Vit E, total fatty acids (TFAs), fatty acids of the phospholipids (FAPLs), total phospholipids (TPLs), 8-isoprostane, thromboxane B2 (TXB2), prostaglandins (PGE2 and 6-keto-PGF1α), interleukin-6 (IL-6), and C-reactive protein (CRP) in serum from 22 COVID-19 patients before and after treatment with Vit E and compared the values with those from 23 healthy subjects (HSs). COVID-19 patients showed a decrease in Vit E, TPLs, FAPLs, and TFAs in serum in comparison to HSs (p ≤ 0.01), and Vit E treatment restored their levels (p ≤ 0.04). Likewise, there was an increase in IL-6 and CRP in COVID-19 patients in comparison with HSs (p ≤ 0.001), and treatment with Vit E decreased their levels (p ≤ 0.001). Treatment with Vit E as monotherapy can contribute to restoring the modified FA profile of the PLs in the SARS-CoV-2 infection, and this leads to a decrease in lipid peroxidation, OS, and the inflammatory process. Full article
(This article belongs to the Section Molecular Medicine)
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18 pages, 6327 KiB  
Article
Evaluating Molecular Mechanism of Viral Inhibition of Aerosolized Smart Nano-Enabled Antiviral Therapeutic (SNAT) on SARS-CoV-2-Infected Hamsters
by Anais N. Bauer, John F. Williams, Lok R. Pokhrel, Selena Garcia, Niska Majumdar, Jeffrey B. Eells, Paul P. Cook and Shaw M. Akula
Toxics 2024, 12(7), 495; https://doi.org/10.3390/toxics12070495 - 5 Jul 2024
Viewed by 956
Abstract
Smart Nano-enabled Antiviral Therapeutic (SNAT) is a promising nanodrug that previously demonstrated efficacy in preclinical studies to alleviate SARS-CoV-2 pathology in hamsters. SNAT comprises taxoid (Tx)-decorated amino (NH2)-functionalized near-atomic size positively charged silver nanoparticles (Tx–[NH2-AgNPs]). Herein, we aimed to [...] Read more.
Smart Nano-enabled Antiviral Therapeutic (SNAT) is a promising nanodrug that previously demonstrated efficacy in preclinical studies to alleviate SARS-CoV-2 pathology in hamsters. SNAT comprises taxoid (Tx)-decorated amino (NH2)-functionalized near-atomic size positively charged silver nanoparticles (Tx–[NH2-AgNPs]). Herein, we aimed to elucidate the molecular mechanism of the viral inhibition and safety of aerosolized SNAT treatment in SARS-CoV-2-infected golden Syrian hamsters. High-resolution transmission electron microscopy (HR-TEM) coupled with energy dispersive spectroscopy (EDS) and ELISAs showed SNAT binds directly to the SARS-CoV-2 virus by interacting with intact spike (S) protein, specifically to S2 subunit. SNAT (≥1 µg/mL) treatment significantly lowered SARS-CoV-2 infections of Calu-3 cells. Extraction-free whole transcriptome assay was used to detect changes in circulatory micronome in hamsters treated intranasally with SNAT (two doses of 10 µg/mL of 2 mL each administered 24 h apart). Uninfected hamsters treated with SNAT had altered circulatory concentrations of 18 microRNAs (8 miRNAs upregulated, 10 downregulated) on day 3 post-treatment compared to uninfected controls. SNAT-induced downregulation of miR-141-3p and miR-200b-3p may reduce viral replication and inflammation by targeting Ythdf2 and Slit2, respectively. Further, SNAT treatment significantly lowered IL-6 expression in infected hamster lungs compared to untreated infected hamsters. Taken together, we demonstrate that SNAT binds directly to SARS-CoV-2 via the S protein to prevent viral entry and propose a model by which SNAT alters the cellular miRNA-directed milieu to promote antiviral cellular processes and neutralize infection. Our results provide insights into the use of low-dose intranasally delivered SNAT in treating SARS-CoV-2 infections in a hamster model. Full article
(This article belongs to the Section Novel Methods in Toxicology Research)
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13 pages, 2758 KiB  
Article
Construction of Fire Safe Thermoplastic Polyurethane/Reduced Graphene Oxide Hierarchical Composites with Electromagnetic Interference Shielding
by Yan Liu, Ansheng Yao, Libi Fu, Shiwei Xie, Yijie Zhang, Peihui Xu, Yuezhan Feng and Yongqian Shi
Molecules 2024, 29(13), 3108; https://doi.org/10.3390/molecules29133108 - 29 Jun 2024
Viewed by 549
Abstract
Incorporating outstanding flame retardancy and electromagnetic interference shielding effectiveness (EMI SE) into polymers is a pressing requirement for practical utilization. In this study, we first employed the principles of microencapsulation and electrostatic interaction-driven self-assembly to encapsulate polyethyleneimine (PEI) molecules and Ti3C [...] Read more.
Incorporating outstanding flame retardancy and electromagnetic interference shielding effectiveness (EMI SE) into polymers is a pressing requirement for practical utilization. In this study, we first employed the principles of microencapsulation and electrostatic interaction-driven self-assembly to encapsulate polyethyleneimine (PEI) molecules and Ti3C2Tx nanosheets on the surface of ammonium polyphosphate (APP), forming a double-layer-encapsulated structure of ammonium polyphosphate (APP@PEI@Ti3C2Tx). Subsequently, flame-retardant thermoplastic polyurethane (TPU) composites were fabricated by melting the flame-retardant agent with TPU. Afterwards, by using air-assisted thermocompression technology, we combined a reduced graphene oxide (rGO) film with flame-retardant TPU composites to fabricate hierarchical TPU/APP@PEI@Ti3C2Tx/rGO composites. We systematically studied the combustion behavior, flame retardancy, and smoke-suppression performance of these composite materials, as well as the flame-retardant mechanism of the expansion system. The results indicated a significant improvement in the interface interaction between APP@PEI@Ti3C2Tx and the TPU matrix. Compared to pure TPU, the TPU/10APP@PEI@1TC composite exhibited reductions of 84.1%, 43.2%, 62.4%, and 85.2% in peak heat release rate, total heat release, total smoke release, and total carbon dioxide yield, respectively. The averaged EMI SE of hierarchical TPU/5APP@PEI@1TC/rGO also reached 15.53 dB in the X-band. Full article
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23 pages, 1057 KiB  
Article
Potential Role of Bioactive Compounds: In Vitro Evaluation of the Antioxidant and Antimicrobial Activity of Fermented Milk Thistle
by Edyta Kucharska, Bartłomiej Grygorcewicz, Monika Spietelun, Patrycja Olszewska, Anna Bobkowska, Joanna Ryglewicz, Anna Nowak, Anna Muzykiewicz-Szymańska, Łukasz Kucharski and Robert Pełech
Appl. Sci. 2024, 14(10), 4287; https://doi.org/10.3390/app14104287 - 18 May 2024
Viewed by 736
Abstract
The group of innovative ingredients in cosmetic preparations includes bio-ferments (Bs), which are characterized by high bioactivity and biocompatibility, and one of the plants rich in bioactive compounds that has a beneficial effect on the skin and the body is Silybum marianum. [...] Read more.
The group of innovative ingredients in cosmetic preparations includes bio-ferments (Bs), which are characterized by high bioactivity and biocompatibility, and one of the plants rich in bioactive compounds that has a beneficial effect on the skin and the body is Silybum marianum. Bio-ferments obtained from this plant are becoming increasingly useful as active ingredients in cosmetics. In the present study, four different bio-ferments were obtained by fermentation of pomace (B-P), extract (B-E), oil (B-O), and seeds (B-S) of milk thistle. Their biodegradability (%B), total polyphenols content (Folin–Ciocalteu method), and antimicrobial, antioxidant (DPPH, ABTS, and FRAP methods), chelating (Fe2+ ions), and reduction (Cu2+ and Fe3+ ions) properties, as well as the acidity, were evaluated. The contact angle using the sessile drop method was assessed to investigate bio-ferments’ impact on skin wettability. Finally, the content of selected phenolic acids in the Bs was evaluated using the HPLC method, while the lactic acid (LA) content was assessed using the GC-MS method. All bio-ferments were characterized by high polyphenols content (13.56 ± 0.10–15.28 ± 0.12 mmol GA/L B), chelating (0.08 ± 0.01–0.17 ± 0.01 mmol Fe2+/L B) and antioxidant activity (DPPH method, 2.41 ± 0.01–3.53 ± 0.01 mmol Tx/L B), and reducing Cu2+ and Fe3+ ions. Gallic acid, protocatechuic acid, caffeic acid, neochlorogenic acid, coumaric acid, and LA were identified in Bs. The most increased antibacterial activity for B-P was observed for a strain of Staphylococcus aureus (MIC = 250 μL/mL) and Pseudomonas aeruginosa (MIC = 250 μL/mL). Simultaneously, B-S demonstrated the highest inhibitory effects against Escherichia coli (MIC = 125 μL/mL), emphasizing the varied antimicrobial profiles of these bio-ferments against different bacterial strains. Research on aerobic biodegradation demonstrated a high level of degradation (%B = 60 ± 1–65 ± 3), and all Bs were categorized as readily degradable according to the OECD classification. Full article
(This article belongs to the Special Issue The Role of Bioactive Natural Products in Health and Disease)
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11 pages, 3246 KiB  
Article
Simulation Validation of an 8-Channel Parallel-Transmit Dipole Array on an Infant Phantom: Including RF Losses for Robust Correlation with Experimental Results
by Jérémie Daniel Clément and Özlem Ipek
Sensors 2024, 24(7), 2254; https://doi.org/10.3390/s24072254 - 1 Apr 2024
Cited by 1 | Viewed by 947
Abstract
It is crucial to demonstrate a robust correlation between the simulated and manufactured parallel-transmit (pTx) arrays performances to release the currently-used, very restrictive safety margins. In this study, we describe the qualitative and quantitative validation of a simulation model with respect to experimental [...] Read more.
It is crucial to demonstrate a robust correlation between the simulated and manufactured parallel-transmit (pTx) arrays performances to release the currently-used, very restrictive safety margins. In this study, we describe the qualitative and quantitative validation of a simulation model with respect to experimental results for an 8-channel dipole array at 7T. An approach that includes the radiofrequency losses into the simulation model is presented and compared to simulation models neglecting these losses. Simulated S-matrices and individual B1+-field maps were compared with experimentally measured quantities. With the proposed approach, an average relative difference of ~1.1% was found between simulated and experimental reflection coefficients, ~4.2% for the 1st coupling terms, and ~9.4% for the 2nd coupling terms. A maximum normalized root-mean-square error of 4.8% was achieved between experimental and simulated individual B1+-field maps. The effectiveness of the simulation model to accurately predict the B1+-field patterns was assessed, qualitatively and quantitatively, through a comparison with experimental data. We conclude that, using the proposed model for radiofrequency losses, a robust correlation is achieved between simulated and experimental data using the 8-channel dipole array at 7T. Full article
(This article belongs to the Special Issue Sensors in Magnetic Resonance Imaging)
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14 pages, 1090 KiB  
Article
Ex Vivo Antiplatelet Effects of Oral Anticoagulants
by Giulia Renda, Valentina Bucciarelli, Giulia Barbieri, Paola Lanuti, Martina Berteotti, Gelsomina Malatesta, Francesca Cesari, Tanya Salvatore, Betti Giusti, Anna Maria Gori, Rossella Marcucci and Raffaele De Caterina
J. Cardiovasc. Dev. Dis. 2024, 11(4), 111; https://doi.org/10.3390/jcdd11040111 - 31 Mar 2024
Viewed by 1209
Abstract
Background: The impact of non-vitamin K antagonist oral anticoagulants (NOACs) on platelet function is still unclear. We conducted a comprehensive ex vivo study aimed at assessing the effect of the four currently marketed NOACs on platelet function. Methods: We incubated blood samples from [...] Read more.
Background: The impact of non-vitamin K antagonist oral anticoagulants (NOACs) on platelet function is still unclear. We conducted a comprehensive ex vivo study aimed at assessing the effect of the four currently marketed NOACs on platelet function. Methods: We incubated blood samples from healthy donors with concentrations of NOACs (50, 150 and 250 ng/mL), in the range of those achieved in the plasma of patients during therapy. We evaluated generation of thrombin; light transmittance platelet aggregation (LTA) in response to adenosine diphosphate (ADP), thrombin receptor-activating peptide (TRAP), human γ-thrombin (THR) and tissue factor (TF); generation of thromboxane (TX)B2; and expression of protease-activated receptor (PAR)-1 and P-selectin on the platelet surface. Results: All NOACs concentration-dependently reduced thrombin generation compared with control. THR-induced LTA was suppressed by the addition of dabigatran at any concentration, while TF-induced LTA was reduced by factor-Xa inhibitors. ADP- and TRAP-induced LTA was not modified by NOACs. TXB2 generation was reduced by all NOACs, particularly at the highest concentrations. We found a concentration-dependent increase in PAR-1 expression after incubation with dabigatran, mainly at the highest concentrations, but not with FXa inhibitors; P-selectin expression was not changed by any drugs. Conclusions: Treatment with the NOACs is associated with measurable ex vivo changes in platelet function, arguing for antiplatelet effects beyond the well-known anticoagulant activities of these drugs. There are differences, however, among the NOACs, especially between dabigatran and the FXa inhibitors. Full article
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13 pages, 2372 KiB  
Article
A Four-Port Dual-Band Dual-Polarized Antenna for Ku-Band Satellite Communications
by Son Trinh-Van, Woo Yong Yang, Hyung Won Cho and Keum Cheol Hwang
Appl. Sci. 2024, 14(7), 2730; https://doi.org/10.3390/app14072730 - 25 Mar 2024
Viewed by 924
Abstract
This paper presents the development of a four-port dual-band dual-polarized antenna for transmitting/receiving (Tx/Rx) applications in Ku-band satellite communications. The antenna consists of two antenna elements sharing a common radiating aperture, a low-band element formed by an L-probe proximity-fed square-ring radiator for [...] Read more.
This paper presents the development of a four-port dual-band dual-polarized antenna for transmitting/receiving (Tx/Rx) applications in Ku-band satellite communications. The antenna consists of two antenna elements sharing a common radiating aperture, a low-band element formed by an L-probe proximity-fed square-ring radiator for operation at the Rx band of 10.7–12.75 GHz, and a high-band element realized by a stacked-patch radiator for operation at the Tx band of 13.75–14.5 GHz. Within a compact multilayer structure, the antenna achieves wide dual-band operation, with each band having the ability to simultaneously operate with dual polarization. An antenna prototype is fabricated and tested to verify its performance. The experimental results show that the proposed antenna achieves an impedance bandwidth of 9.28–12.96 GHz (13.21–15.32 GHz), an isolation value between two orthogonal polarizations of 12 dB (12.4 dB), and a peak gain of 6.63 dBi (5.42 diBi) at the low band (high band). Tx/Rx isolation of more than 14 dB is achieved in both the Rx band and Tx band. Full article
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16 pages, 18737 KiB  
Article
A 5G NR FR2 Beamforming System with Integrated Transceiver Module
by Ayush Bhatta, Md Kamrojjaman, Sanghoon Sim and Jeong-Geun Kim
Sensors 2024, 24(6), 1983; https://doi.org/10.3390/s24061983 - 20 Mar 2024
Viewed by 1325
Abstract
This paper presents a 5G new radio (NR) FR2 beamforming system with an integrated transceiver module. A real-time operating module providing enhanced flexibility and capability has been proposed. The integrated RF beamforming system with an integrated transceiver module can be operated in 8Tx-8Rx [...] Read more.
This paper presents a 5G new radio (NR) FR2 beamforming system with an integrated transceiver module. A real-time operating module providing enhanced flexibility and capability has been proposed. The integrated RF beamforming system with an integrated transceiver module can be operated in 8Tx-8Rx mode configuration simultaneously. A series-fed structure 8 × 7 microstrip antenna array for compact size and improved directivity is employed in the RF beamforming module. The RF beamforming module incorporates a custom 28 GHz, eight-channel fully differential beamforming IC (BFIC). An eight-channel BFIC in a phased-array beamforming system offers advantages in terms of increased antenna density and improved beam steering precision. The RF beamforming module is integrated with an RF transceiver module that enables the simultaneous up-conversion and down-conversion of the baseband signal. The RF transmitter module consists of a transmitter, a receiver, a signal generator, a power supply, and a control unit. The RF beamforming system can scan horizontally from −50° to +50° with a step of 10°. To achieve an optimized beam pattern, a calibration was conducted. The transmit and receive conversion gain of around 20 dB is achieved with the transceiver module. To verify the communication performance of the manufactured integrated RF beamforming system, a real-time wireless video transmission/reception test was performed at a frequency of 28 GHz, and the video file was transmitted smoothly in real time without interruption within a range of ±50°. Full article
(This article belongs to the Special Issue Antenna Array Design for Wireless Communications)
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15 pages, 8934 KiB  
Article
SERS Performance of Ti3C2Tx MXene-Based Substrates Correlates with Surface Morphology
by Farnoush Salehtash, Adriana Annušová, Anastasiia Stepura, Yaryna Soyka, Yuriy Halahovets, Monika Hofbauerová, Matej Mičušík, Mário Kotlár, Peter Nádaždy, Paweł Albrycht, Peter Šiffalovič, Matej Jergel, Mária Omastová and Eva Majková
Materials 2024, 17(6), 1385; https://doi.org/10.3390/ma17061385 - 18 Mar 2024
Cited by 1 | Viewed by 1117
Abstract
The surface-enhanced Raman scattering (SERS) properties of low-dimensional semiconducting MXene nanoflakes have been investigated over the last decade. Despite this fact, the relationship between the surface characteristics and SERSing performance of a MXene layer has yet to be comprehensively investigated and elucidated. This [...] Read more.
The surface-enhanced Raman scattering (SERS) properties of low-dimensional semiconducting MXene nanoflakes have been investigated over the last decade. Despite this fact, the relationship between the surface characteristics and SERSing performance of a MXene layer has yet to be comprehensively investigated and elucidated. This work shows the importance of surface morphology on the overall SERS effect by studying few-layer Ti3C2Tx MXene-based SERS substrates fabricated by vacuum-assisted filtration (VAF) and spray coating on filter paper. The VAF deposition results in a dense MXene layer suitable for SERS with high spot-to-spot and substrate-to-substrate reproducibility, with a significant limit of detection (LoD) of 20 nM for Rhodamine B analyte. The spray-coated MXenes film revealed lower uniformity, with a LoD of 50 nM for drop-casted analytes. Moreover, we concluded that the distribution of the analyte deposited onto the MXene layer is affected by the presence of MXene aggregates created during the deposition of the MXene layer. Accumulation of the analyte molecules in the vicinity of MXene aggregates was observed for drop-casted deposition of the analyte, which affects the resulting SERS enhancement. Ti3C2Tx MXene layers deposited on filter paper by VAF offer great potential as a cost-effective, easy-to-manufacture, yet robust, platform for sensing applications. Full article
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16 pages, 5537 KiB  
Article
A 2.4 GHz Wide-Range CMOS Current-Mode Class-D PA with HD2 Suppression for Internet of Things Applications
by Nam-Seog Kim
Sensors 2024, 24(5), 1616; https://doi.org/10.3390/s24051616 - 1 Mar 2024
Viewed by 869
Abstract
Short-range Internet of Things (IoT) sensor nodes operating at 2.4 GHz must provide ubiquitous wireless sensor networks (WSNs) with energy-efficient, wide-range output power (POUT). They must also be fully integrated on a single chip for wireless body area networks (WBANs) and wireless personal [...] Read more.
Short-range Internet of Things (IoT) sensor nodes operating at 2.4 GHz must provide ubiquitous wireless sensor networks (WSNs) with energy-efficient, wide-range output power (POUT). They must also be fully integrated on a single chip for wireless body area networks (WBANs) and wireless personal area networks (WPANs) using low-power Bluetooth (BLE) and Zigbee standards. The proposed fully integrated transmitter (TX) utilizes a digitally controllable current-mode class-D (CMCD) power amplifier (PA) with a second harmonic distortion (HD2) suppression to reduce VCO pulling in an integrated system while meeting harmonic limit regulations. The CMCD PA is divided into 7-bit slices that can be reconfigured between differential and single-ended topologies. Duty cycle distortion compensation is performed for HD2 suppression, and an HD2 rejection filter and a modified C-L-C low-pass filter (LPF) reduce HD2 further. Implemented in a 28 nm CMOS process, the TX achieves a wide POUT range of from 12.1 to −31 dBm and provides a maximum efficiency of 39.8% while consuming 41.1 mW at 12.1 dBm POUT. The calibrated HD2 level is −82.2 dBc at 9.93 dBm POUT, resulting in a transmitter figure of merit (TX_FoM) of −97.52 dB. Higher-order harmonic levels remain below −41.2 dBm even at 12.1 dBm POUT, meeting regulatory requirements. Full article
(This article belongs to the Section Internet of Things)
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32 pages, 4744 KiB  
Article
Comparison of the Regenerative Metabolic Efficiency of Lipid Extracts from Microalgae Nannochloropsis oceanica and Chlorococcum amblystomatis on Fibroblasts
by Anna Stasiewicz, Tiago Conde, Maria do Rosario Domingues, Pedro Domingues, Michał Biernacki and Elżbieta Skrzydlewska
Antioxidants 2024, 13(3), 276; https://doi.org/10.3390/antiox13030276 - 24 Feb 2024
Viewed by 1485
Abstract
UVA radiation leads to oxidative stress and inflammation in skin cells. Therefore, the aim of this study was to compare the effect of lipid extracts from microalgae Nannochloropsis oceanica (N.o.) (marine) and Chlorococcum amblystomatis (C.a.) (freshwater) on the redox [...] Read more.
UVA radiation leads to oxidative stress and inflammation in skin cells. Therefore, the aim of this study was to compare the effect of lipid extracts from microalgae Nannochloropsis oceanica (N.o.) (marine) and Chlorococcum amblystomatis (C.a.) (freshwater) on the redox balance and PUFA metabolism in human skin fibroblasts modified by UVA. Lipid extracts from both types of microalgae introduced into the fibroblast medium after UVA irradiation significantly reduced the level of ROS and enhanced expression of Nrf2, which increased the activity/level of antioxidants (SOD1/2, CAT, GSH, Trx). The reduction in oxidative stress was accompanied by a decrease in the level of 4-HNE, its protein adducts and protein carbonyl groups. Microalgae also reduced the activity of COX1/2, FAAH and MAGL increased by UVA, and as a consequence, the level of lipid mediators (especially after N.o.) decreased, both from the group of endocannabinoids (AEA, 2-AG, PEA) and eicosanoids (PGE2, 15d-PGJ2, TXB2, 15-HETE), acting mainly through receptors related to G protein, the expression of which increases after UVA. This further contributed to the reduction in oxidative stress and pro-inflammatory signaling at NF-κB and TNFα levels. Therefore, it is suggested that lipid extracts from both N.o. and C.a. microalgae can be used to regenerate fibroblast metabolism disturbed by UVA radiation. Full article
(This article belongs to the Section Natural and Synthetic Antioxidants)
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16 pages, 11312 KiB  
Article
Fully Integrated 24-GHz 1TX-2RX Transceiver for Compact FMCW Radar Applications
by Goo-Han Ko, Seung-Jin Moon, Seong-Hoon Kim, Jeong-Geun Kim and Donghyun Baek
Sensors 2024, 24(5), 1460; https://doi.org/10.3390/s24051460 - 23 Feb 2024
Cited by 1 | Viewed by 1286
Abstract
A fully integrated 24-GHz radar transceiver with one transmitter (TX) and two receivers (RXs) for compact frequency modulated continuous wave (FMCW) radar applications is here presented. The FMCW synthesizer was realized using a fractional-N phase-locked loop (PLL) and programmable chirp generator, which are [...] Read more.
A fully integrated 24-GHz radar transceiver with one transmitter (TX) and two receivers (RXs) for compact frequency modulated continuous wave (FMCW) radar applications is here presented. The FMCW synthesizer was realized using a fractional-N phase-locked loop (PLL) and programmable chirp generator, which are completely integrated in the proposed transceiver. The measured output phase noise of the synthesizer is −80 dBc/Hz at 100 kHz offset. The TX consists of a three-bit bridged t-type attenuator for gain control, a two-stage drive amplifier (DA) and a one-stage power amplifier (PA). The TX chain provides an output power of 13 dBm while achieving <0.5 dB output power variation within the range of 24 to 24.25 GHz. The RX with a direct conversion I-Q structure is composed of a two-stage low noise amplifier (LNA), I-Q generator, mixer, transimpedance amplifier (TIA), a two-stage biquad band pass filter (BPF), and a differential-to-single (DTS) amplifier. The TIA and the BPF employ a DC offset cancellation (DCOC) circuit to suppress the strong reflection signal and TX-RX leakage. The RX chain exhibits an overall gain of 100 dB. The proposed radar transceiver is fabricated using a 65 nm CMOS technology. The transceiver consumes 220 mW from a 1 V supply voltage and has 4.84 mm2 die size including all pads. The prototype FMCW radar is realized with the proposed transceiver and Yagi antenna to verify the radar functionality, such as the distance and angle of targets. Full article
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17 pages, 10586 KiB  
Article
The Complexity of Colour/Textile Interaction in Digital Printing as an Integral Part of Environmental Design
by Marijana Tkalec, Martina Glogar, Željko Penava, Petra Forte Tavčer, Danjela Kuščer and Izabela Stojanoska
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Abstract
Textile materials are an essential part of contemporary architecture, the environment, and urban spaces due to their unique appearance and qualities, as it is now possible to achieve both a structural function and an aesthetic quality with textiles. As colour is one of [...] Read more.
Textile materials are an essential part of contemporary architecture, the environment, and urban spaces due to their unique appearance and qualities, as it is now possible to achieve both a structural function and an aesthetic quality with textiles. As colour is one of the most important characteristics of textile material, it is also important to understand the relationships between colour and textile material with different surface qualities. In order to explain the complexity of different textile materials and the appearance of colours, which consequently affects the colour properties, this paper analyses this phenomenon. The presented research analyses the dependence of the reproduction quality and colour appearance on fabrics of different construction and structural characteristics, i.e., the texture of the textile material, printed using digital inkjet technology. The aim of this work is to investigate the influence of various structural features of textiles on the colour appearance of digitally printed textile substrates, to monitor the quality of colour reproduction, and to analyse the behaviour of a reactive dye droplet on textile substrates. Printing of a particular shape was performed using a Dimatix Materials Printer DMP-2831 piezoelectric inkjet device (provided by the J. Stefan Institute, Ljubjana, Slovenia; manufactured by Fujifilm Dimatix Inc., 2230 Martin Avenue, Santa Clara, CA, USA). The behaviour of the ink delivered by the needle of the tensiometer DSA20E, Kruess GmbH (provided by the J. Stefan Institute, Ljubjana, Slovenia; manufactured by Kruess Scientific Instruments (Shanghai) Co., Ltd. Futong Dong Dajie 10 Baoneng Center, Tower B, Room 605 Chaoyang District, Beijing 100102, China), on the surface of the fabric was analysed. The samples were digitally printed on a Mimaki digital printer Tx2-1600 (provided by University of Ljubljana Faculty of Natural Science and Engineering, Slovenia EU; manufactured by Mimaki, 2182-3 Shigeno-Otsu, Tomi-city, Nagano, Japan), with reactive dyes, which were first pretreated in a bath with a specific solution. The statistical method of image analysis and microscopic imaging were used to obtain the characteristics of the porosity, texture, and roughness parameters. All results are presented from colouristic analysis based on the objectification of colour and colour differences. The objective values of the parameters of lightness (L*), chroma (C*), and hue (h°) show the significant influence of the structure and properties of the substrate on colour reproduction, and significant changes were obtained, which were confirmed by the evaluation of the colour differences. The results confirm the influence of the substrate structure on colour properties. Furthermore, it is essential to consider this complexity in the context of environmental colour design when utilising (coloured) textile installations/materials in architecture and urban spaces, i.e., in the environment. Full article
(This article belongs to the Special Issue Colour: Art and Design in Urban Environments)
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