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We present a 2 × 2 polarization-insensitive switch on a 220-nm silicon-on-insulator platform, employing a balanced Mach-Zehnder interferometer (MZI) structure. This design incorporates polarization-insensitive adiabatic couplers, polarization rotators based on mode hybridization and evolution, and thermo-optic mode-insensitive phase shifters with wide waveguides. The switch exhibits broadband polarization-insensitive characteristics, with extinction ratios larger than 15 dB, insertion losses less than 2.3 dB, and polarization-dependent losses less than 1 dB for wavelengths ranging from 1500 nm to 1600 nm. The power consumption required for simultaneously switching the fundamental transverse electric (TE0) and transverse magnetic (TM0) polarized modes is 29.1 mW. These results highlight the potential of the switch as a building block for on-chip polarization-division-multiplexed optical interconnects.
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We propose an all-silicon design of a multi-band transverse-magnetic-pass (TM-pass) polarizer. The device is based on one-dimensional gratings that work under different regimes that depend on the polarization. With a tapered structure, it is revealed that the operation bandwidth can be extended by multiplexing the diffraction in O-band and the reflection in S-, C-, and L-bands for the transverse-electric (TE) mode. By simulation, we achieve a 343 nm device bandwidth with insertion loss (IL) < 0.4 dB and polarization extinction ratio (PER) > 20 dB. The operation wavelength range covers commonly-used optical telecommunication bands including the O-, S-, C-, and L- bands. Experimental results also show IL < 1.6 dB and PER > 20 dB from 1265 nm to 1360 nm corresponding to the O-band, and from 1500 nm to 1617 nm that corresponds to the C-band. The device is a single-etched design on the standard 220 nm silicon-on-insulator (SOI) with silicon oxide cladding. Such a simple and compatible design paves the way for developing practical multi-band silicon photonic integrated circuits.
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We design and experimentally demonstrate a broadband 1310/1550 nm wavelength demultiplexer based on a multimode interference coupler with a tapered internal photonic crystal (PC) structure for the silicon-on-insulator platform. The tapered internal PC structure is engineered to reflect the C-band light while transmitting the O-band light. Novel PC nanotapers are introduced for the internal PC structure that effectively suppress the sidelobe of the photonic bandgap and enable our device to be operable over the O-band. The device was fabricated using electron beam lithography, and its performance has been experimentally characterized. The measured extinction ratios are higher than 15 dB over a 74 nm bandwidth from 1286 to 1360 nm at the O-band, and over a 103 nm bandwidth from 1527 to 1630 nm that covers the C-band and the L-band.
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We characterize the impact of the modulator material on chirp, digital signal processing (DSP) algorithms and system-level performance in coherent digital optical links. We compare theoretically, in simulations and experimentally the lithium niobate (LiNbO3), indium phosphide (InP) and silicon (Si) integrated platforms. Distortions to vector diagrams are traced back to modulation physics, and are interpreted as quadrature crosstalk. In a back-to-back BPSK setup with an RF drive signal amplitude of 1.5Vπ, we measure chirp parameters α of ~0, 0.10 and 0.06 and error vector magnitude EVMRMS of 5.3%, 9.4% and 10.6% with the LiNbO3, InP and Si modulators respectively. Both α and EVMRMS are found to scale with the RF signal amplitude. In simulations, using a polynomial fit over a sinusoidal fit when pre-compensating the Si modulator transfer function slightly improves EVM (-0.6%). We also show that Si-related distortions can impact the efficiency of symbol timing recovery. In conclusion, phase and attenuation distortions in InP and Si modulators deteriorate the overall performance in coherent links, and cannot be neglected for large RF signal amplitudes. These results will benefit the optical communications community.
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We demonstrate a compact high-performance adiabatic 3-dB coupler for the silicon-on-insulator platform. The refractive index of the gap region between two coupling waveguides is effectively increased using subwavelength grating, which leads to high-performance operation and a compact design footprint, with a mode-evolution length of only 25 µm and an entire device length of 65 µm. The designed adiabatic 3-dB coupler has been fabricated using electron beam lithography and the feature size used in our design is CMOS compatible. The fabricated device is characterized in the wavelength range from 1500 nm to 1600 nm, with a measured power splitting ratio better than 3 ± 0.27 dB and an average insertion loss of 0.20 dB.
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We design and demonstrate Fabry-Perot resonators with transverse coupling using Bragg gratings as reflectors on the silicon-on-insulator (SOI) platform. The effects of tailoring the cavity length and the coupling coefficient of the directional coupler on the spectral characteristics of the device are studied. The fabricated resonators achieved an extinction ratio (ER) of 37.28 dB and a Q-factor of 3356 with an effective cavity length of 110 µm, and an ER of 8.69 dB and a Q-factor of 23642 with a 943 µm effective cavity length. The resonator structure presented here has the highest reported ER on SOI and provides additional degrees of freedom compared to an all-pass ring resonator to tune the spectral characteristics.
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We present experimental results of photonic crystal ring resonators (PhCRRs) fabricated on the CMOS-compatible, silicon-on-insulator platform via 193-nm deep-UV lithography. Our dispersion-engineering design approach is compared to experimental results, showing very good agreement between theory and measurements. Specifically, we report a mean photonic band-edge wavelength of 1546.2 ± 5.8 nm, a 0.2% variation from our targeted band-edge wavelength of 1550 nm. Methods for the direct calculation of the experimental, discrete dispersion relation and extraction of intrinsic quality factors for a highly-dispersive resonator are discussed. A maximum intrinsic quality factor of ≈83,800 is reported, substantiating our design method and indicating that high-throughput optical lithography is a viable candidate for PhCRR fabrication. Finally, through comparison of the mean intrinsic quality and slowdown factors of the PhCRRs and standard ring resonators, we present evidence of an increase in light-matter interaction strength with simultaneous preservation of microcavity lifetimes.
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We demonstrate two single-etched sub-wavelength grating coupler (SWGC) designs for O-band application, one targeting at high coupling efficiency and the other targeting at broad operating bandwidth. The high-efficiency SWGC has a measured peak coupling efficiency of -3.8 dB and a 3-dB bandwidth of 40 nm, and the broadband SWGC has a measured peak coupling efficiency of -4.3 dB and a 3-dB bandwidth of 71 nm. Focusing gratings have been used in our SWGCs to reduce the design footprints and the dimensions of our SWGCs are smaller than 45 µm × 24 µm. The back reflections of our SWGCs are suppressed to be below -15 dB over the wavelength range from 1260 nm to 1360 nm.
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Background: Dendrobium, with profound botanical importance, reveals a rich composition of bioactive compounds, including polysaccharides, flavonoids, alkaloids, and diverse amino acids, holding promise for skin regeneration. However, the precise mechanism remains elusive. Seeking a potent natural remedy for wound healing, exocyst vesicles were successfully isolated from Dendrobium. Aims of the Study: This investigation aimed to employ bioinformatics and in vivo experiments to elucidate target genes of Dendrobium-derived nanovesicles in skin wound healing, focusing on immune infiltration and senescence characteristics. Materials and Methods: C57 mice experienced facilitated wound healing through Dendrobium-derived nanovesicles (DDNVs). Bioinformatics analysis and GEO database mining identified crucial genes by intersecting immune-related, senescence-related, and PANoptosis-associated genes. The identified genes underwent in vivo validation. Results: DDNVs remarkably accelerated skin wound healing in C57 mice. Bioinformatics analysis revealed abnormal expression patterns of immune-related, senescence-related, and pan-apoptosis-related genes, highlighting an overexpressed IL-1ß and downregulated IL-18 in the model group, Exploration of signaling pathways included IL-17, NF-kappa B, NOD-like receptor, and Toll-like receptor pathways. In vivo experiments confirmed DDNVs' efficacy in suppressing IL-1ß expression, enhancing wound healing. Conclusion: Plant-derived nanovesicles (PDNV) emerged as a natural, reliable, and productive approach to wound healing. DDNVs uptake by mouse skin tissues, labeled with a fluorescent dye, led to enhanced wound healing in C57 mice. Notably, IL-1ß overexpression in immune cells and genes played a key role. DDNVs intervention effectively suppressed IL-1ß expression, accelerating skin wound tissue repair.
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Dendrobium , Animales , Ratones , Dendrobium/metabolismo , Cicatrización de Heridas/genética , Piel/metabolismo , FN-kappa B/metabolismo , Transducción de SeñalRESUMEN
Rhodiola rosea (Golden Root Extract; RR) is an herbaceous perennial, which is native to high altitude areas, such as East Asia, Central Asia, Siberia, and North America. It has been studied for its positive pharmacological effects on health. However, only a handful of studies have evaluated the effects of RR as an exercise supplement for sport and physical activity. The aim of this study was to evaluate whether Rhodiola can be used as a supplement to improve human exercise ability. Studies were reviewed in accordance with the PRISMA guidelines and conducted between August and November, 2021. Databases searched included Cochrane, Embase, Web of Science, PubMed and East View Universal Database. Related terms were combined with keywords and MeSH subject headings using the corresponding Boolean operators: Rhodiola rosea, arctic root, roseroot, golden root, hongjingtian, and sports and exercise. A total of 10 papers were reviewed. Most of the studies reported that RR supplementation has a positive effect on athletic ability and sports performance, and no obvious adverse reactions were reported. Subjects taking RR showed a reduction in pain and muscle damage after exercise training, improved skeletal muscle damage, enhanced antioxidant capacity thereby reducing oxidative stress, reduced RPE scores, and improved athletic explosive power, but did not reduce the rating of perceived exertion (RPE) scores. RR appears to act as a safe and effective supplementation for sport and exercise.
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[This corrects the article DOI: 10.3389/fnut.2022.856287.].
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Inflammatory immune response plays a key role in exercise-induced injury and healing; however, the relevant regulatory mechanisms of immune infiltration in exercise-induced injuries remain less studied. In the present study, a highly efficient system for screening immunity-related biomarkers and immunomodulatory ability of natural nutritional supplements was developed by integrating intelligent data acquisition, data mining, network pharmacology, and computer-assisted target fishing. The findings demonstrated that resting natural killer cells showed a higher rate of infiltration after exercise, whereas naive B cells and activated dendritic cells showed higher rate of infiltration before exercise. Four key genes, namely PRF1, GZMB, CCL4, and FASLG, were associated with exercise-induced injuries and inflammatory immune response. In total, 26 natural compounds including echinacoside, eugenol, tocopherol, and casuariin were predicted by using the HERB databases. Molecular docking analysis showed that GZMB, FASLG, and CCL4 bound to echinacoside. In vivo experiments in mice showed that after 30 min swimming, natural killer (NK) cells showed high infiltration rates, and the key genes (GZMB, PRF1, FASLG, and CCL4) were highly expressed; however, echinocandin significantly reduced the level of NK cells and decreased the expression of the four key genes post exercise. This natural nutritional supplement may act to protect against inflammatory injury after exercise by suppressing specific immune infiltration.
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Myocardial ischemia/reperfusion (I/R) injury is a clinically severe complication, which can cause high rates of disability and mortality particularly in patients with myocardial infarction, yet the molecular mechanisms underlying this process remain unclear. This study aimed to explore the protective effects of ß-sitosterol against myocardial I/R injury and to elucidate the underlying molecular mechanisms. Our results showed that hypoxia/reoxygenation (H/R) treatment suppressed cell viability, induced cell apoptosis and reactive oxygen species production, increased caspase-3 and -9 activities, upregulated caspase-3 and -9 protein expressions, downregulated the Bcl-2 protein expression, and reduced the mitochondrial membrane potential. ß-Sitosterol treatment attenuated H/R-induced cardiomyocyte injury. Moreover, ß-sitosterol treatment counteracted the inhibitory effects of H/R treatment on the peroxisome proliferator-activated receptor gamma (PPARγ) expression and enhanced effects of H/R treatment on the NF-κB expression in cardiomyocytes. Furthermore, inhibition of PPARγ impaired the protective actions of ß-sitosterol against H/R-induced cardiomyocyte injury. In the I/R rats, ß-sitosterol treatment reduced the myocardial infarcted size and apoptosis, which was attenuated by the inhibition of PPARγ. In conclusion, our results demonstrate that ß-sitosterol protected against in vitro H/R-induced cardiomyocyte injury and in vivo myocardial I/R injury. The ß-sitosterol-mediated cardioprotective effects may involve the modulation of PPARγ/NF-κB signalling during myocardial I/R injury. Further studies are required to further explore the clinical application of ß-sitosterol in the myocardial I/R injury.
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PURPOSE: Berberine (BBR) is an effective component of Huanglian and has shown to attenuate atherosclerosis (AS); however, the detailed mechanism of BBR-mediated protective actions against AS remains elusive. This study was undertaken to examine the effects of BBR on aortic atherosclerotic plaque stability and the expression of autophagy-related proteins in AS rats with damp-heat syndrome or yang deficiency. METHODS: Thirty SD rats were randomly divided into (1) control (CON); (2) damp-heat syndrome atherosclerosis (AS + DH); (3) yang deficiency syndrome atherosclerosis (AS + YX); (4) damp-heat syndrome atherosclerosis + BBR (AS + DH + BBR); (5) yang deficiency syndrome, atherosclerosis + BBR (AS + YX + BBR); and (6) damp-heat syndrome, atherosclerosis + BBR + 3-methyladenine (AS + DH + BBR + 3-MA) (n = 5/group) groups. Pathological morphology, macrophage plaque infiltration, inflammation, and LC3-II and P62 expression were assessed. RESULTS: Compared with the CON group, the AS + DH and AS + YX groups had an increased plaque area in the aortic tissue with substantial foam cell and macrophage infiltration, and increased levels of IL-1ß and TNF-α (P < 0.01). After four weeks of BBR intervention, the plaque area in the AS + DH + BBR group was reduced with decreased foam cells and macrophage infiltration, and decreased levels of TNF-α and IL-1ß, whereas LC3-II protein expression was increased and P62 protein expression was decreased in the AS + DH + BBR group when compared to AS + DH group. In addition, the AS + DH + BBR + 3-MA group exhibited a significantly enlarged plaque, substantial foam cell and macrophage infiltration, increased levels of IL-1ß and TNF-α, and decreased LC3-II and P62 (P < 0.01) expression when compared to the AS + DH + BBR group. CONCLUSION: Our results indicated that the BBR could inhibit arterial plaque formation and alleviate the inflammatory response in the aortic tissues in the AS rats with damp-heat syndrome possibly via promoting autophagy. The molecular mechanisms of BBR-mediated protective effects in this animal model still require further investigation.
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Aterosclerosis/tratamiento farmacológico , Autofagia/efectos de los fármacos , Berberina/farmacología , Calor , Placa Aterosclerótica/tratamiento farmacológico , Administración Oral , Animales , Aterosclerosis/patología , Berberina/administración & dosificación , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Masculino , Placa Aterosclerótica/patología , Ratas , Ratas Sprague-Dawley , Relación Estructura-Actividad , SíndromeRESUMEN
BACKGROUND: This study aimed to evaluate the role of Semen Brassicae, a common Traditional Chinese Medicine, in the treatment of hypertension. METHODS: Spontaneously hypertensive rats (SHRs) were divided into five groups and were gavaged with either distilled water, water-decocted solution from Semen Brassicae (0.5, 1 or 2 g/kg), or nifedipine (2.7 mg/kg). Normal rats gavaged with distilled water were used as a control. Systolic (SBP) and diastolic blood pressure (DBP) were measured using a non-invasive method. After 8 weeks of administration, all animals were anesthetized. Abdominal aortic serum was collected to measure serum factors; the thoracic aorta was collected for hematoxylin and eosin staining and western blot analysis. RESULTS: Both SBP and DBP were significantly decreased after Semen Brassicae treatment. Endothelin-1 and angiotensin II levels in abdominal aortic serum, as well as the levels of inflammatory factors interleukin (IL)-1ß, IL-6, and tumor necrosis factor-alpha, were significantly decreased after Semen Brassicae treatment. The wall thickness of the thoracic aorta was significantly reduced after Semen Brassicae treatment. Nitric oxide level and the activity of superoxide dismutase and glutathione peroxidase were significantly increased, and malondialdehyde level was significantly decreased in the abdominal aortic serum after Semen Brassicae treatment. Semen Brassicae treatment increased the levels of peroxisome proliferator-activated receptor gamma and IκB-α and decreased the levels of intercellular adhesion molecule 1, monocyte chemoattractant protein-1, von Willebrand factor, p-IκB-α and p-p65 NF-κB. CONCLUSIONS: In conclusion, water-decocted solution from Semen Brassicae can decrease blood pressure, improve vascular remodeling, and attenuate oxidative stress and inflammation in SHRs.