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1.
ACS Appl Mater Interfaces ; 16(19): 24987-24998, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38712685

RESUMO

For traditional ferroelectric field-effect transistors (FeFETs), enhancing the polarization domain of bulk ferroelectric materials is essential to improve device performance. However, there has been limited investigation into the enhancement of polarization field in two-dimensional (2D) ferroelectric material such as CuInP2S6 (CIPS). In this study, similar to bulk ferroelectric materials, CIPS exhibited enhanced polarization field upon application of external cyclic voltage. Moreover, unlike traditional ferroelectric materials, the polarization enhancement of CIPS is not due to redistribution of the defect but rather originates from a mechanism: the long-distance migration of Cu ions. We termed this mechanism the "wake-up-like effect". After incorporating the wake-up-like effect into the graphene/CIPS/WSe2 FeFET device, we successfully increased the hysteresis window and enhanced the current on/off ratio by 4 orders of magnitude. Moreover, the FeFET yielded remarkable achievements, such as multilevel nonvolatile memory with 21 distinct conductance levels, a high on/off ratio exceeding 106, a long retention time exceeding 103 s, and neuromorphic computing with 93% accuracy at recognizing handwritten digits. Introducing the wake-up-like effect to 2D CIPS may pave the way for innovative approaches to achieve advanced multilevel nonvolatile memory and neuromorphic computing capabilities for next-generation micro-nanoelectronic devices.

2.
Circ Arrhythm Electrophysiol ; : e012486, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38690652

RESUMO

BACKGROUND: 12,13-dihydroxy-9Z-octadecenoic acid (12,13-diHOME) has shown potential in protecting against heart disease, but its relationship with atrial fibrillation (AF) remains unknown. METHODS: Coronary sinus (CS) and femoral vein blood samplings were synchronously collected from AF and non-AF subjects (paroxysmal supraventricular tachycardia or idiopathic premature ventricular complexes) who underwent catheter ablation. First, untargeted metabolomic profiling was performed in a discovery cohort (including 12 AF and 12 non-AF subjects) to identify the most promising CS or femoral vein metabolite. Then, the selected metabolite was further measured in a validation cohort (including 119 AF and 103 non-AF subjects) to confirm its relationship with left atrium remodeling and 1-year postablation recurrence of AF. Finally, the biological function of the selected metabolite was validated in a rapid-paced cultured HL-1 atrial cardiomyocytes model. RESULTS: Metabolomic analysis identified CS 12,13-diHOME as the most pronounced change metabolite correlated with left atrium remodeling in the discovery cohort. In the validation cohort, CS 12,13-diHOME was significantly lower in patients with AF than non-AF controls (84.32±20.13 versus 96.24±23.56 pg/mL; P<0.01), and associated with worse structural, functional, and electrical remodeling of left atrium. Multivariable regression analyses further demonstrated that decreased CS 12,13-diHOME was an independent predictor of 1-year postablation recurrence of AF (odds ratio, 0.754 [95% CI, 0.648-0.920]; P=0.005). Biological function validations showed that 12,13-diHOME treatment significantly protect the cell viability, improved the expression of MHC (myosin heavy chain) and L-type calcium channel α1c, and attenuated mitochondrial damage in the rapid-paced cultured HL-1 cardiomyocytes model. CONCLUSIONS: CS metabolite 12,13-diHOME is decreased in patients with AF and can serve as a novel biomarker for left atrium remodeling.

3.
Sci Rep ; 14(1): 8486, 2024 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605105

RESUMO

In this study, we compared the transcriptome of longissimus dorsi muscle between Guizhou Xiang pigs (XP) and Western commercial Large White pigs (LW), which show diffirent meat quality between them. In terms of meat quality traits, the pH 45 min, color score, backfat thickness, and intramuscular fat (IMF) content were higher in Xiang pigs than in Large White pigs (P < 0.01), while the drip loss, lean meat percentage, shear force, and longissimus dorsi muscle area of Xiang pigs were lower than that of Large White pigs (P < 0.01). Nutrients such as monounsaturated fatty acid (MUFA), total amino acids (TAA), delicious amino acids (DAA) and essential amino acids (EAA) in Xiang pigs were higher than that in Large White pigs, and the proportion of polyunsaturated fatty acid (PUFA) of Xiang pigs was significantly lower than Large White pigs (P < 0.01). Transcriptome analysis identified 163 up-regulated genes and 88 genes down-regulated in Xiang pigs longissimus dorsi muscle. Combined with the correlation analysis and quantitative trait locis (QTLs) affecting meat quality, a total of 227 DEGs were screened to be significantly associated with meat quality values. Enrichment analysis indicated that numerous members of genes were gathered in muscle development, adipogenesis, amino acid metabolism, fatty acid metabolism and synthesis. Of those, 29 genes were identified to be hub genes that might be related with the meat quality of Xiang pig, such as MYOD1, ACTB, ASNS, FOXO1, ARG2, SLC2A4, PLIN2, and SCD. Thus, we screened and identified the potential functional genes for the formation of meat quality in Xiang pigs, which provides a corresponding theoretical basis for the study of the molecular regulatory mechanism of pork quality and the improvement of pork quality.


Assuntos
Músculo Esquelético , Transcriptoma , Suínos/genética , Animais , Músculo Esquelético/metabolismo , Perfilação da Expressão Gênica , Carne , Aminoácidos/metabolismo , China
4.
Ecotoxicol Environ Saf ; 276: 116303, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38599157

RESUMO

Certain insecticides are known to have estrogenic effects by activating estrogen receptors through genomic transcription. This has led researchers to associate specific insecticide use with an increased breast cancer risk. However, it is unclear if estrogen receptor-dependent pathways are the only way in which these compounds induce carcinogenic effects. The objective of this study was to determine the impact of the pyrethroid insecticide permethrin on the growth of estrogen receptor negative breast cancer cells MDA-MB-231. Using tandem mass spectrometric techniques, the effect of permethrin on cellular protein expression was investigated, and gene ontology and pathway function enrichment analyses were performed on the deregulated proteins. Finally, molecular docking simulations of permethrin with the candidate target protein was performed and the functionality of the protein was confirmed through gene knockdown experiments. Our findings demonstrate that exposure to 10-40 µM permethrin for 48 h enhanced cell proliferation and cell cycle progression in MDA-MB-231. We observed deregulated expression in 83 upregulated proteins and 34 downregulated proteins due to permethrin exposure. These deregulated proteins are primarily linked to transmembrane signaling and chemical carcinogenesis. Molecular docking simulations revealed that the overexpressed transmembrane signaling protein, G protein-coupled receptor 39 (GPR39), has the potential to bind to permethrin. Knockdown of GPR39 partially impeded permethrin-induced cellular proliferation and altered the expression of proliferation marker protein PCNA and cell cycle-associated protein cyclin D1 via the ERK1/2 signaling pathway. These findings offer novel evidence for permethrin as an environmental breast cancer risk factor, displaying its potential to impact breast cancer cell proliferation via an estrogen receptor-independent pathway.


Assuntos
Proliferação de Células , Receptor alfa de Estrogênio , Inseticidas , Simulação de Acoplamento Molecular , Permetrina , Receptores Acoplados a Proteínas G , Permetrina/toxicidade , Humanos , Proliferação de Células/efeitos dos fármacos , Inseticidas/toxicidade , Linhagem Celular Tumoral , Receptor alfa de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neoplasias da Mama/patologia , Feminino , Transdução de Sinais/efeitos dos fármacos
5.
BMC Genomics ; 25(1): 164, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336605

RESUMO

BACKGROUND: Guizhou black goat is one of the indigenous black goat breeds in the southwest region of Guizhou, China, which is an ordinary goat for mutton production. They are characterized by moderate body size, black coat, favorite meat quality with tender meat and lower odor, and tolerance for cold and crude feed. However, little is known about the genetic characteristics or variations underlying their important economic traits. RESULTS: Here, we resequenced the whole genome of Guizhou black goat from 30 unrelated individuals breeding in the five core farms. A total of 9,835,610 SNPs were detected, and 2,178,818 SNPs were identified specifically in this breed. The population structure analysis revealed that Guizhou black goat shared a common ancestry with Shaanbei white cashmere goat (0.146), Yunshang black goat (0.103), Iran indigenous goat (0.054), and Moroccan goat (0.002). However, Guizhou black goat showed relatively higher genetic diversity and a lower level of linkage disequilibrium than the other seven goat breeds by the analysis of the nucleotide diversity, linkage disequilibrium decay, and runs of homozygosity. Based on FST and θπ values, we identified 645, 813, and 804 selected regions between Guizhou black goat and Yunshang black goat, Iran indigenous goat, and cashmere goats. Combined with the results of XP-EHH, there were 286, 322, and 359 candidate genes, respectively. Functional annotation analysis revealed that these genes are potentially responsible for the immune response (e.g., CD28, CD274, IL1A, TLR2, and SLC25A31), humility-cold resistance (e.g., HBEGF, SOSTDC1, ARNT, COL4A1/2, and EP300), meat quality traits (e.g., CHUK, GAB2, PLAAT3, and EP300), growth (e.g., GAB2, DPYD, and CSF1), fertility (e.g., METTL15 and MEI1), and visual function (e.g., PANK2 and NMNAT2) in Guizhou black goat. CONCLUSION: Our results indicated that Guizhou black goat had a high level of genomic diversity and a low level of linkage disequilibrium in the whole genome. Selection signatures were detected in the genomic regions that were mainly related to growth and development, meat quality, reproduction, disease resistance, and humidity-cold resistance in Guizhou black goat. These results would provide a basis for further resource protection and breeding improvement of this very local breed.


Assuntos
Cabras , Seleção Genética , Humanos , Animais , Cabras/genética , Genoma , Genômica , Fenótipo , Polimorfismo de Nucleotídeo Único , Proteínas Adaptadoras de Transdução de Sinal/genética
6.
Nat Commun ; 15(1): 1631, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388545

RESUMO

Metasurfaces have exhibited unprecedented degree of freedom in manipulating electromagnetic (EM) waves and thus provide fantastic front-end interfaces for smart systems. Here we show a framework for perception enhancement based on vision-driven metasurface. Human's eye movements are matched with microwave radiations to extend the humans' perception spectrum. By this means, our eyes can "sense" visual information and invisible microwave information. Several experimental demonstrations are given for specific implementations, including a physiological-signal-monitoring system, an "X-ray-glasses" system, a "glimpse-and-forget" tracking system and a speech reception system for deaf people. Both the simulation and experiment results verify evident advantages in perception enhancement effects and improving information acquisition efficiency. This framework can be readily integrated into healthcare systems to monitor physiological signals and to offer assistance for people with disabilities. This work provides an alternative framework for perception enhancement and may find wide applications in healthcare, wearable devices, search-and-rescue and others.


Assuntos
Movimentos Oculares , Olho , Humanos , Simulação por Computador , Vidro , Percepção
7.
Opt Lett ; 49(3): 518-521, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300048

RESUMO

We designed a broadband lens along with a graphene/silicon photodiode for wide spectral imaging ranging from ultraviolet to near-infrared wavelengths. By using five spherical glass lenses, the broadband lens, with the modulation transfer function of 0.38 at 100 lp/mm, corrects aberrations ranging from 340 to 1700 nm. Our design also includes a broadband graphene/silicon Schottky photodiode with the highest responsivity of 0.63 A/W ranging from ultraviolet to near-infrared. By using the proposed broadband lens and the broadband graphene/silicon photodiode, several single-pixel imaging designs in ultraviolet, visible, and near-infrared wavelengths are demonstrated. Experimental results show the advantages of integrating the lens with the photodiode and the potential to realize broadband imaging with a single set of lens and a detector.

8.
Cell Div ; 19(1): 6, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38374109

RESUMO

BACKGROUND: Coix seed extract (CSE), a traditional Chinese medicine, has been reported as an adjunctive therapy in cancers. However, the molecular targets are largely unclear. The study is designed to unveil its function in lung adenocarcinoma (LUAD) and the possible molecular mechanism. METHODS: The HERB database was utilized to predict the molecular targets of the Coix seed, followed by prognostic value prediction in the Kaplan-Meier Plotter database. LUAD cells were infected with sh-KCTD9 after co-culture with CSE, and cell viability, growth, proliferation, and apoptosis were determined. The substrates of KCTD9 were predicted using a protein-protein interaction network and verified. The expression of PD-L1, the contents of TNF-α, IFN-γ, CXCL10, and CXCL9 in the co-culture system of LUAD cells and T cells and the proliferation of T cells were evaluated to study the immune escape of LUAD cells in response to CSE and sh-KCTD9. Lastly, tumor growth and immune escape were observed in tumor-bearing mice. RESULTS: CSE inhibited malignant behavior and immune escape of LUAD cells, and the reduction of KCTD9 reversed the inhibitory effect of CSE on malignant behavior and immune escape of LUAD cells. Knockdown of KCTD9 expression inhibited ubiquitination modification of TOP2A, and knockdown of TOP2A suppressed immune escape of LUAD cells in the presence of knockdown of KCTD9. CSE exerted anticancer effects in mice, but the reduction of KCTD9 partially compromised the anticancer effect of CSE. CONCLUSION: CSE inhibits immune escape and malignant progression of LUAD through KCTD9-mediated ubiquitination modification of TOP2A.

9.
J Invest Dermatol ; 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38360199

RESUMO

Chronic itch is a common and complex symptom often associated with skin diseases such as atopic dermatitis (AD). Although IL-27 is linked to AD, its role and clinical significance in itch remain undefined. We sought to investigate IL-27 function in itch using tissue-specific transgenic mice, various itch models, behavior scoring, RNA sequencing, and cytokine/kinase array. Our findings show that IL-27 receptors were overexpressed in human AD skin. Intradermal IL-27 injection failed to directly induce itch in mice but upregulated skin protease-activated receptor 2 (PAR2) transcripts, a key factor in itch and AD. IL-27 activated human keratinocytes, increasing PAR2 transcription and activity. Coinjection of SLIGRL (PAR2 agonist) and IL-27 in mice heightened PAR2-mediated itch. In addition, IL-27 boosted BST2 transcription in sensory neurons and keratinocytes. BST2 was upregulated in AD skin, and its injection in mice induced itch-like response. BST2 colocalized with sensory nerve branches in AD skin from both human and murine models. Sensory neurons released BST2, and mice with sensory neuron-specific BST2 knockout displayed reduced itch responses. Overall, this study provides evidence that skin IL-27/PAR2 and neuronal IL-27/BST2 axes are implicated in cutaneous inflammation and pruritus. The discovery of neuronal BST2 in pruritus shed light on BST2 in the itch cascade.

11.
Opt Express ; 31(23): 37882-37891, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-38017908

RESUMO

Half-wave wall is the most common method of achieving electromagnetic (EM) transparency. Transmission windows can be formed when reflected waves are out of phase. Due to the interference mechanism, these windows are dependent on the frequency and incident angle of EM waves, leading to limited bandwidth, especially under extreme angles. In this letter, we propose to extend the bandwidth of the transmission window under extreme angles by utilizing dispersion. To this end, long metallic wires are embedded into the half-wave wall matrix, without increasing the physical thickness. Due to the plasma-like behavior of metallic wires under TE-polarization, the effective permittivity of the half-wave wall, rather than keeping constant, increases with frequency nonlinearly. Such a dispersion will boost wideband transparency in two aspects. On one hand, an additional transmission window will be generated where the effective permittivity equals that of the air; on the other hand, the 1st- and 2nd-order half-wave windows will be made quite closer. By tailoring the dispersion, the three windows can be merged to enable wideband transparency under extreme incident angles. A proof-of-principle prototype was designed, fabricated, and measured to verify this strategy. Both simulated and measured results show that the prototype can operate in the whole Ku-band under incident angle [70°, 85°] for TE-polarized waves. This work provides an effective method of achieving wideband EM transparency under extreme angles and may find applications in radar, communications, and others.

12.
Front Immunol ; 14: 1239592, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37965323

RESUMO

Persistent inflammation and associated pain significantly impact individuals' quality of life, posing substantial healthcare challenges. Proinflammatory cytokines, released by activated macrophages, play crucial roles in the development of chronic inflammatory conditions such as rheumatoid arthritis. To identify and evaluate potential therapeutic interventions targeting this process for mitigating inflammation and pain, we created myeloid cell-specific knockout of Vamp3 (vesicle-associated membrane protein 3) mice (Vamp3 Δmyel) by crossing LysM-Cre mice with newly engineered Vamp3flox/flox mice. Bone marrow-derived macrophages and peritoneal resident macrophages from Vamp3 Δmyel mice exhibited a significant reduction in TNF-α and IL-6 release compared to control mice. Moreover, Vamp3 deficiency led to decreased paw edema and ankle joint swelling induced by intraplantar injection of complete Freund's adjuvant (CFA). Furthermore, Vamp3 depletion also mitigated CFA-induced mechanical allodynia and thermal hyperalgesia. Mechanistically, Vamp3 loss ameliorated the infiltration of macrophages in peripheral sites of the hind paw and resulted in reduced levels of TNF-α and IL-6 in the CFA-injected paw and serum. RT-qPCR analysis demonstrated downregulation of various inflammation-associated genes, including TNF-α, IL-6, IL-1ß, CXCL11, TIMP-1, COX-2, CD68, and CD54 in the injected paw at the test day 14 following CFA administration. These findings highlight the novel role of Vamp3 in regulating inflammatory responses and suggest it as a potential therapeutic target for the development of novel Vamp-inactivating therapeutics, with potential applications in the management of inflammatory diseases.


Assuntos
Interleucina-6 , Fator de Necrose Tumoral alfa , Animais , Camundongos , Citocinas/metabolismo , Adjuvante de Freund , Hiperalgesia/induzido quimicamente , Hiperalgesia/genética , Inflamação/tratamento farmacológico , Macrófagos Peritoneais/metabolismo , Dor/induzido quimicamente , Qualidade de Vida , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Proteína 3 Associada à Membrana da Vesícula
13.
Phys Chem Chem Phys ; 25(42): 28716-28726, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37850228

RESUMO

Two-dimensional (2D) materials are excellent candidates for advanced flexible electronics and gas sensors. Herein, we systematically investigate the layer-dependent electronic structures, mechanical properties and gas sensing characteristics of the newly synthesized γ-SnSe based on first-principles calculations. Bulk γ-SnSe is a typical van der Waals layered material with an indirect narrow band gap, while monolayer and multilayer γ-SnSe can be obtained through mechanical exfoliation due to its low cleavage energy. The band gap of γ-SnSe gradually increases with decreasing layers, reaching a value of 2.25 eV for the monolayer due to weakened interlayer coupling. Mechanical analysis reveals strong anisotropy in multilayer γ-SnSe, whereas the monolayer exhibits a negative Poisson's ratio (-0.023/-0.025). Additionally, based on the analysis of electronic structures, adsorption energies and charge transfer of the host materials after adsorption of various gases, it is found that the γ-SnSe monolayer demonstrates enhanced sensitivity and selectivity towards NO, NO2, and SO2 compared to CO, CO2, H2S and NH3. These findings highlight the potential of γ-SnSe as an excellent gas-sensitive material for the detection of nitrogen oxides and sulfur dioxide.

14.
Braz J Microbiol ; 54(3): 1943-1954, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37594656

RESUMO

The Xifeng Hot Spring is one of the eight largest hot springs in China, which is rich in radon gas and sulphur in karst scenery. Little is known about the microbiota structure in the spring. The water was collected from three sites containing the outlet of spring water discharge site (OWD), spring pool for tourist (SPT) and sewage effluent pool (SEP) in the Xifeng Hot Spring and further analyzed by culture-independent technique and culture-dependent method. A total of 57 phyla were identified from the water samples. The dominate phyla at OWD was Bacteroidetes (46.93%), while it was Proteobacteria in both sites of SEP and SPT with relative richness of 61.9% and 94.9%, respectively. Two bacteria, Deinococcus and Hymenobacter, that confirmed to be radiation-resistant, seven sulphur bacteria and three thermophilic bacteria were detected from Xifeng Hot Spring. Furthermore, it was found that genus Flavobacterium was susceptible to environmental change with abundance of 11 ~ 2825 times higher in OWD than the other two groups. Compared bacteria from the OWD group with that from 14 hot springs in six countries, total 94 unique genera bacteria were found out from the Xifeng Hot Spring including four thiometabolism-related bacteria (Propionispira, Desulforegula, Desulfobacter and Desulfococcus) and the thermophilic bacterium (Symbiobacterium). Using microbial culturing and isolation technology, sixteen strains were isolated from the water samples of three sites. The diversity of microbiota was abundant and variable along with the niche changed in conditions and surroundings. It indicated that numbers of valuable bacteria resources could be explored from the special surroundings of Xifeng Hot Spring.


Assuntos
Fontes Termais , Bactérias/genética , China , Esgotos , Enxofre , Água
15.
Micromachines (Basel) ; 14(7)2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37512718

RESUMO

Two-dimensional (2D) materials with novel structures and electronic properties are promising candidates for the next generation of micro- and nano-electronic devices. Herein, inspired by the recent experimental synthesis of penta-NiN2 (ACS Nano, 2021, 15, 13539-13546), we propose for the first time a novel ternary penta-NiPN monolayer with high stability by partial element substitution. Our predicted penta-NiPN monolayer is a quasi-direct bandgap (1.237 eV) semiconductor with ultrahigh carrier mobilities (103-105 cm2V-1s-1). Furthermore, we systematically studied the adsorption properties of common gas molecules (CO, CO2, CH4, H2, H2O, H2S, N2, NO, NO2, NH3, and SO2) on the penta-NiPN monolayer and its effects on electronic properties. According to the energetic, geometric, and electronic analyses, the penta-NiPN monolayer is predicted to be a promising candidate for NO and NO2 molecules. The excellent electronic properties of and the unique selectivity of the penta-NiPN monolayer for NO and NO2 adsorption suggest that it has high potential in advanced electronics and gas sensing applications.

16.
ACS Appl Mater Interfaces ; 15(30): 37026-37037, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37465891

RESUMO

Achieving the conversion from surface waves (SWs) to propagating waves has captivated long-standing interest, and various ingenious metasurfaces benefiting from the powerful control capability for electromagnetic waves are able to realize efficient SWs directional radiation. Nevertheless, most existing schemes still suffer from the bottlenecks of single radiation channel, uncontrollable radiation intensity, and immutable radiation pattern, which immensely hinder their practical application in high-integration intelligent devices. Herein, a series of appealing strategies are proposed to achieve the dual-channel SWs directional radiation with customizable radiation intensity and switchable radiation pattern. The dual-channel SWs radiation metadevice based on the phase modulation metasurface is designed to directionally radiate SWs in left-handed circular polarized channel and right-handed circular polarized channel and possesses the broadband frequency scanning characteristic. More strikingly, the intensity-customizable dual-channel SWs radiation metadevice loaded with lumped resistors can control the realized gain of two circular polarized radiation beams, and the pattern-switchable dual-channel SWs radiation metadevice loaded with PIN diodes can dynamically adjust the radiation direction of the radiation beams. Numerous simulations and experiments of the proof-of-concept prototypes with modular design corroborate the theoretical predictions. Our methodology shows unprecedented flexibility in regulating SWs directional radiation and has enormous potential in engineering applications.

17.
Opt Express ; 31(9): 13923-13932, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37157267

RESUMO

Metasurfaces have exhibited versatile capacities of controlling electromagnetic (EM) waves due to the high degree of freedom of designing artificially engineered meta-atoms. For circular polarization (CP), broadband phase gradient metasurfaces (PGMs) can be realized based on P-B geometric phase by rotating meta-atoms; while for linear polarization (LP), realization of broadband phase gradients has to resort to P-B geometric phase during polarization conversion and polarization purity has to be sacrificed for broadband properties. It is still challenging to obtain broadband PGMs for LP waves without polarization conversion. In this paper, we propose the design of 2D PGMs by combining the inherently wideband geometric phases and non-resonant phases of meta-atom, under the philosophy of suppressing Lorentz resonances that usually bring about abrupt phase changes. To this end, an anisotropic meta-atom is devised which can suppress abrupt Lorentz resonances in 2D for both x- and y-polarized waves. For y-polarized waves, the central straight wire is in perpendicular to electric vector Ein of incident waves, Lorentz resonance cannot be excited although the electrical length approaches or even exceeds half a wavelength. For x-polarized waves, the central straight wire is in parallel with Ein, a split gap is opened on the center of the straight wire so as to avoid Lorentz resonance. In this way, the abrupt Lorentz resonances are suppressed in 2D and the wideband geometric phase and the gradual non-resonant phase are left for broadband PGM design. As a proof of concept, a 2D PGM prototype for LP waves was designed, fabricated and measured in microwave regime. Both simulated and measured results show that the PGM can achieve broadband beam deflection for reflected waves for both x- and y-polarized waves in broadband, without changing the LP state. This work provides a broadband route to 2D PGMs for LP waves and can be readily extended to higher frequencies such as terahertz and infrared regimes.

20.
Cardiovasc Diabetol ; 22(1): 124, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-37226247

RESUMO

BACKGROUND: Atrial fibrillation (AF) and heart failure (HF) frequently coexist because of their similar pathological basis. However, whether sodium-glucose cotransporter 2 inhibitor (SGLT2i), a novel class of anti-HF medication, decreases the risk of AF in HF patients remains unclear. OBJECTIVES: The aim of this study was to assess the relationship between SGLT2i and AF in HF patients. METHODS: A meta-analysis of randomized controlled trails evaluating the effects of SGLT2i on AF in HF patients was performed. PubMed and ClinicalTrails.gov were searched for eligible studies until 27 November 2022. The risk of bias and quality of evidence were assessed through the Cochrane tool. Pooled risk ratio of AF for SGLT2i versus placebo in eligible studies was calculated. RESULTS: A total of 10 eligible RCTs examining 16,579 patients were included in the analysis. AF events occurred in 4.20% (348/8292) patients treated with SGLT2i, and in 4.57% (379/8287) patients treated with placebo. Meta-analysis showed that SGLT2i did not significantly reduce the risk of AF (RR 0.92; 95% CI 0.80-1.06; p = 0.23) in HF patients when compared to placebo. Similar results remained in the subgroup analyses, regardless of the type of SGLT2i, the type of HF, and the duration of follow-up. CONCLUSIONS: Current evidences showed that SGLT2i may have no preventive effects on the risk of AF in patients with HF. TRANSLATIONAL PERSPECTIVE: Despite HF being one of the most common heart diseases and conferring increased risk for AF, affective prevention of AF in HF patients is still unresolved. The present meta-analysis demonstrated that SGLT2i may have no preventive effects on reducing AF in patients with HF. How to effectively prevent and early detect the occurrence of AF is worth discussing.


Assuntos
Fibrilação Atrial , Cardiopatias , Insuficiência Cardíaca , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/epidemiologia , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/prevenção & controle , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico
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