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1.
Phys Chem Chem Phys ; 26(24): 17083-17089, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38842138

RESUMEN

A SERS substrate with high sensitivity and reusability was proposed. The chip consists of multiple ZnO microcavities loaded with silver particles. Based on structural characteristics, this coupling between cavity modes and localized surface plasmon modes can highly localize the electric field, where experimental results revealed a detection limit of 10-11 M for R6G. In addition, during carrier control in semiconductors with localized electromagnetic fields, our substrate also exhibits high self-cleaning efficiency and in situ detection stability. Even in a dry environment, it exhibits excellent light-mediated cleaning ability across multiple reuse test cycles. The convenient, rinse-free substrate, with its cost-effective and sustainable features, shows great promise for the study on detection and degradation of active materials.

2.
J Cosmet Laser Ther ; : 1-8, 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38943685

RESUMEN

Microneedle fractional radiofrequency (MFRF) has been used to improve photoaging and scars. This study aimed to evaluate the efficacy and safety of MFRF with basic fibroblast growth factor (bFGF) for facial atrophic acne scars and skin rejuvenation by blinded visual evaluation, self-report, and reflective confocal microscopy (RCM). Fifteen subjects were randomized to the MFRF with bFGF group and fifteen to the MFRF group. All subjects underwent three-session therapy and a follow-up period. Significant group differences were in ECCA, global improvement score, satisfaction, and downtime before and after treatment. Combination therapy could be more effective than monotherapy for acne scars and facial rejuvenation. In addition, RCM can be used to observe the changes in skin collagen before and after treatment in evaluating cosmetic efficacy.

3.
Opt Express ; 31(4): 5363-5377, 2023 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-36823818

RESUMEN

Recently, the study of non-Hermitian topological edge and corner states in sonic crystals (SCs) and photonic crystals (PCs) has drawn much attention. In this paper, we propose a Wannier-type higher-order topological insulator (HOTI) model based on the kagome PC containing dimer units and study its non-Hermitian topological corner states. When balanced gain and loss are introduced into the dimer units with a proper parity-time symmetric setting, the system will show asymmetric Wannier bands and can support two Hermitian corner states and two pairs of complex-conjugate or pseudo complex-conjugate non-Hermitian corner states. These topological corner states are solely confined at three corners of the triangular supercell constructed by the trivial and non-trivial kagome PCs, corresponding to a topological spatial mode selection effect. As compared to the non-Hermitian quadrupole-type HOTIs, the non-Hermitian Wannier-type HOTIs can realize totally topological spatial mode selection by using much lower coefficients of gain and loss. Our results pave the way for the development of novel non-Hermitian photonic topological devices based on Wannier-type HOTIs.

4.
Nanotechnology ; 34(26)2023 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-36996801

RESUMEN

Metal nanogaps can confine electromagnetic field into extremely small volumes, exhibiting strong surface plasmon resonance effect. Therefore, metal nanogaps show great prospects in enhancing light-matter interaction. However, it is still challenging to fabricate large-scale (centimeter scale) nanogaps with precise control of gap size at nanoscale, limiting the practical applications of metal nanogaps. In this work, we proposed a facile and economic strategy to fabricate large-scale sub-10 nm Ag nanogaps by the combination of atomic layer deposition (ALD) and mechanical rolling. The plasmonic nanogaps can be formed in the compacted Ag film by the sacrificial Al2O3deposited via ALD. The size of nanogaps are determined by the twice thickness of Al2O3with nanometric control. Raman results show that SERS activity depends closely on the nanogap size, and 4 nm Ag nanogaps exhibit the best SERS activity. By combining with other porous metal substrates, various sub-10 nm metal nanogaps can be fabricated over large scale. Therefore, this strategy will have significant implications for the preparation of nanogaps and enhanced spectroscopy.

5.
Liver Transpl ; 28(6): 1063-1077, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34919773

RESUMEN

The effects of mammalian target of rapamycin (mTOR) inhibitors (sirolimus [SRL] and everolimus [EVL]) on survival in liver transplantation (LT) recipients with hepatocellular carcinoma (HCC) remain the subject of intense research. Therefore, we performed this systematic review and meta-analysis to investigate the potential survival benefits of mTOR inhibitors (mTORis). Embase, PubMed, and Cochrane Central Register of Controlled Trials (CENTRAL) were searched for all randomized controlled trials (RCTs) and cohort studies investigating effects of SRL or EVL on LT recipients for HCC. The primary outcomes were 1-, 2-, 3-, and 5-year overall survival (OS), and the secondary outcomes were 1-, 2-, and 3-year recurrence-free survival (RFS) and adverse effects. Pooled relative risks (RRs) with 95% confidence interval (CI) were calculated by a fixed or random effects model with Mantel-Haenszel weighting. Subgroup analyses were performed according to crucial clinical characteristics. We also conducted sensitivity analyses to assess the reliability of our findings. A total of 17 studies were included. OS was improved in both RCTs (1 year: RR, 1.04; 95% CI, 1.00-1.08; 2 years: RR, 1.09; 95% CI, 1.02-1.16; 3 years: RR, 1.13; 95% CI, 1.04-1.24; 5 years: RR, 1.13; 95% CI, 1.02-1.26) and cohort studies (1 year: RR, 1.13; 95% CI, 1.06-1.20; 2 years: RR, 1.24; 95% CI, 1.16-1.32; 3 years: RR, 1.24; 95% CI, 1.15-1.34; 5 years: RR, 1.17; 95% CI, 1.10-1.24), with a lower risk of renal toxicity (RR, 0.75; 95% CI, 0.60 to 0.93). The 1-, 2-, and 3-year RFS were also improved. Current evidence indicates that SRL- or EVL-based immunosuppression improves OS and RFS with a lower risk of renal toxicity compared with mTORi-free immunosuppression. Nevertheless, results must be interpreted with caution.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Trasplante de Hígado , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/cirugía , Everolimus/efectos adversos , Humanos , Inmunosupresores/efectos adversos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/cirugía , Trasplante de Hígado/efectos adversos , Sirolimus/efectos adversos
6.
Opt Express ; 30(7): 11495-11503, 2022 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-35473092

RESUMEN

Over the past few years, zero refraction (ZR) represents an important breakthrough in field of distinctive dynamic optical beam tuning for double-zero-index (media with zero relative permittivity and permeability) photonic crystals (PCs). Because accidental ZR effects for conventional PCs is sensitive to the structural or refractive index parameters, how to enhance the robustness of ZR design is vital for applications. Here, we report a pioneering wave property that reveals a non-accidental Dirac-like cone dispersion composed of low- or high-energy bands, corresponding to dual-insensitive ZR effects for both transverse magnetic and transverse electric polarizations based on the same annular PCs. The performance of non-accidental ZR is simultaneously based on refractive index-insensitivity and structural- insensitivity, attributed to a satisfactory filling ratio.

7.
Opt Lett ; 47(3): 678-681, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-35103706

RESUMEN

Recently, terahertz (THz) nonreciprocal and functionality-switchable devices have drawn much attention. Here we report a magnetic-free THz unidirectional perfect absorber as well as a functionality-switchable device between the band-pass filter and perfect absorber based on dielectric-graphene multilayers containing a VO2 defect layer. We provide a theoretical explanation for the nonreciprocal transmission properties. The working frequencies of these devices can be tailored by using graphene layers of different chemical potentials.

8.
BMC Gastroenterol ; 22(1): 546, 2022 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-36581813

RESUMEN

BACKGROUND: Biliary tract cancers (BTCs) are a series of heterogeneous malignancies that are broadly grouped based on the anatomical site where they arise into subtypes including intrahepatic cholangiocarcinoma (ICC), extrahepatic cholangiocarcinoma (ECC), gallbladder cancer (GBC), and ampulla of Vater cancer (AVC). METHODS AND RESULTS: The present study provides an overview of the epidemiology of the various BTCs based on data from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) database from 2000 to 2018. Distinct differences in both incidence and mortality rates were observed for these BTCs as a function of age, sex, ethnicity, and calendar year. In 2018, BTCs emerged as the fifth most prevalent form of alimentary tract cancer in the USA. While the incidence and mortality of ICC appear to be increasing, the incidence rates of GBC, ECC, and AVC have remained stable, as have the corresponding mortality rates. The most common and deadliest BTCs in 2018 were ICC and GBC among males and females, respectively. The ethnic groups exhibiting the highest incidence rates of these different BTCs were American Indians and Alaska Natives for GBC, and Asian and Pacific Islanders for ICC, ECC, and AVC. The incidence of all of these forms of BTC rose with age. There were some variations in BTCs in terms of staging, locoregional surgical treatments, adjuvant therapies, and prognostic outcomes from 2000 to 2018. CONCLUSIONS: The epidemiological characteristics, staging, locoregional surgical treatments, adjuvant therapies, and prognostic outcomes were distinct for each of these BTCs.


Asunto(s)
Neoplasias de los Conductos Biliares , Neoplasias del Sistema Biliar , Colangiocarcinoma , Neoplasias de la Vesícula Biliar , Masculino , Femenino , Humanos , Estados Unidos/epidemiología , Neoplasias de los Conductos Biliares/epidemiología , Neoplasias de los Conductos Biliares/patología , Neoplasias del Sistema Biliar/epidemiología , Neoplasias del Sistema Biliar/patología , Colangiocarcinoma/epidemiología , Colangiocarcinoma/patología , Neoplasias de la Vesícula Biliar/epidemiología , Neoplasias de la Vesícula Biliar/patología , Conductos Biliares Intrahepáticos
9.
Appl Opt ; 61(26): 7731-7740, 2022 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-36256375

RESUMEN

In the past few years, designing multifunctional all-optical logic devices has attracted more and more attention in integrated optical computing. We report a metal-insulator-metal based four-port all-optical logic gate device containing two parallel straight waveguides and a ring resonator. We employ the scattering matrix method to analyze the coupling mechanisms of the hybrid waveguide and adopt the finite-difference time-domain method to design four fundamental logic functions of AND, OR, XOR, and NOT based on the all-optical coherent control of the four-port system under three symmetrically incident conditions. We demonstrate that these logic functions can be freely modulated by changing the phase difference of the input light at two resonant wavelengths or in a broad band. The logic gate device proposed shows a simple structure with multiple functions, multiple channels, and convenience in fabrication, and can be applied in parallel optical computing based on wavelength division multiplexing technology.

10.
Opt Express ; 29(9): 13314-13330, 2021 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-33985068

RESUMEN

In the past few years, designing tunable and multifunctional terahertz devices has become a hot research area in terahertz science and technology. In this work, we report a study on one-dimensional anisotropic photonic crystals (1D APCs) containing graphene and phase-change material VO2. We numerically demonstrate the band-pass filtering, perfect absorption, comb-shaped extraordinary optical transmission and Fano-like resonance phenomenon in pure 1D APCs and 1D APCs with a VO2 defect layer under different conditions of a tangential wave vector. The performance of these phenomena in the terahertz region can be modulated by changing the chemical potential of graphene. The band-pass filter and perfect absorber functions of 1D APCs with a VO2 defect layer can be freely switched by changing the phase of VO2. We employ the equivalent-permittivity model and dispersion-relation equation to give reasonable explanations on these behaviors.

11.
Opt Express ; 28(4): 5367-5377, 2020 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-32121759

RESUMEN

Negative refraction (NR), self-collimation (SC), and zero refraction (ZR) effects of photonic crystals play an important role in beam steering. In this work, we report a multifunctional beam steering concept in photonic crystals, i.e., integrating two or three of the NR, SC, and ZR effects together at the same frequency. We find the square-lattice dielectric ring photonic crystal is an ideal candidate to realize the switchable function of ZR-SC while the square-lattice dielectric ring photonic crystal is more suitable for realizing the ZR-SC, ZR-NR, and ZR-SC-NR functions. The photonic band theory and an equivalent waveguide model are employed to explain these switchable functions in conventional and annular photonic crystals.

12.
Opt Lett ; 45(23): 6362-6365, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-33258812

RESUMEN

In this Letter, we report a scheme to design multifunctional and multichannel all-optical logic gates based on the in-plane coherent control of localized surface plasmons in an Au nanorod (NR) array on the Si substrate. By using theoretical analysis and structural optimization, we numerically demonstrate a four-channel all-optical logic gate device that can switch three basic logic operations on each NR only by controlling the phase differences of incident beams. This device is ultra-compact in size and shows high extensibility for parallel logic operations, which may be applied in future high-speed on-chip integrated optical computing.

13.
Opt Lett ; 43(24): 6065-6068, 2018 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-30548005

RESUMEN

We report the experimental and theoretical study on the complementary planar metamaterial with asymmetrical air nanorods. Three high-quality samples are fabricated by the focused ion beam technique. Multi-band Fano-like resonances and selective electric field confinement in the visible-near infrared range are presented and well explained by the bonding/anti-boding and coupled mode theories of plasmonic resonators.

14.
Opt Express ; 25(14): 16867-16878, 2017 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-28789186

RESUMEN

We report new models for out-of-plane focusing and manipulation of terahertz beams based on a silicon/copper grating covered by monolayer graphene. Dependences of focusing and manipulation of terahertz beams on the chemical potential and scattering rate of graphene are investigated. Based on the graphene/silicon grating model, we demonstrate that the focal distance and intensity are sensitively influenced by the chemical potential. Based on the graphene/copper grating model, we show how 2 to 1 and 3 to 1 modulation of terahertz beams can be efficiently realized through tuning the chemical potential of graphene. These tunable beam focusing and manipulation effects are well explained by the diffraction theory of optical images and the surface plasmon polariton theory of graphene. Our proposed devices are of compact structures, high electro-optical tunability and good repeatability, and they are expected to have prospective applications in terahertz communications, imaging, sensing, and so on.

15.
Opt Express ; 24(22): 25224-25232, 2016 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-27828460

RESUMEN

We report a super-resolution strategy based on pure/hybrid nanoscale solid immersion lenses (n-SILs) under dark-field illumination. Dependences of the focusing performance of pure n-SILs on different diameters, locations, and substrates are investigated. Simulation results demonstrate a higher resolution (up to a 22.8% improvement) of pure n-SILs under dark-field illumination than convergent plane wave illumination. A hybrid n-SIL with a higher-index nanorod embedded into the n-SIL is proposed. Under dark-field illumination, the hybrid n-SIL can generate a near-field focal spot with a much higher resolution (~λ/8) that is beyond the Abbe diffraction limit in the nanorod. These results have potential applications in data storage, near-field mapping and spectra, and nanoscale lithography.

16.
Appl Opt ; 52(27): 6676-84, 2013 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-24085166

RESUMEN

In this paper, we have systematically investigated the polarization-insensitive and broad-angle self-collimation behavior in a square-lattice two-dimensional photonic crystal (PhC) with rectangular air holes. By analyzing the band structures and the corresponding equi-frequency contours (EFCs), it is found that such PhC can show special dispersion properties when the half-length L and half-width W of rectangular air holes are appropriately changed. First, compared with conventional square-lattice PhCs with circular or square air holes, such PhC is easier to support polarization-insensitive self-collimation (PISC) based on the EFCs for the second band. Meanwhile, the PISC behavior such as working frequency range and effective incident angle can be more flexibly adjusted by changing the structural parameters of rectangular air holes. Second, such PhC can show long flat EFCs for the TM-3 band. This is quite helpful for supporting broad-angle self-collimation. In particular, when L=0.5a and W/L=0.8, this PhC will degenerate to a one-dimensional grating PhC. It can show good all-angle self-collimation behavior with an improved relative bandwidth (about 19.98%) compared with previous works. It also presents advantages in practical applications due to a relatively convenient fabrication process.

17.
BMJ Open ; 13(5): e068969, 2023 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-37169506

RESUMEN

OBJECTIVE: The purpose of this systematic review and meta-analysis was to investigate whether glucocorticoid might be beneficial after hepatectomy. DESIGN: Systematic review and meta-analysis. DATA SOURCES: PubMed, Embase, Cochrane Library and Web of Science. ELIGIBILITY CRITERIA: We included studies assessing the efficacy of perioperative glucocorticoid administration in patients undergoing liver surgery. DATA EXTRACTION AND SYNTHESIS: Four data bases were retrieved for all randomised controlled trials. We considered postoperative complications, hospital stay and postoperative chemistry evaluations as outcomes. Pooled effects of dichotomic variables were expressed as relative risk (RR) with a 95% CI. The mean difference was used for continuous variables and an inverse variance statistical method was adopted. RESULTS: Fourteen studies with 1205 patients were included. Lower risk of overall complications was associated with glucocorticoid (RR, 0.77; 95% CI 0.64 to 0.92), while no difference was found in hospital stay (RR, 0.02; 95% CI -0.47 to 0.51). There were also improvements in postoperative chemistry evaluations including interleukin 6 on day 1 and 3, C reactive protein on day 1, 2 and 3, international normalised ratio on day 2, total bilirubin on day 1, 2, 3 and 5, albumin on day 1. CONCLUSION: Current evidence indicated that perioperative glucocorticoid administration for patients undergoing hepatectomy reduced the risk of overall complications with inhibited postoperative inflammatory response and improved postoperative liver function. PROSPERO REGISTRATION NUMBER: CRD42022307533.


Asunto(s)
Glucocorticoides , Complicaciones Posoperatorias , Humanos , Complicaciones Posoperatorias/prevención & control , Hígado/cirugía , Ensayos Clínicos Controlados Aleatorios como Asunto
18.
Heliyon ; 9(3): e14574, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36950611

RESUMEN

Background: The prognosis of gallbladder cancer (GBC) is dismal. This study aimed to compare the outcomes of adjuvant chemoradiotherapy (ACR) with those of surgery alone (S) and adjuvant chemotherapy (AC). Method: The Surveillance, Epidemiology, and End Results (SEER) Program database was used to identify patients diagnosed with GBC and undergoing surgery between 2004 and 2015. The patients were divided into the S, AC, and ACR groups according to their treatment. Categorical variables were compared by Pearson's chi-square test, and a 1:1:1 propensity score matching analysis (PSM) was performed. Overall survival was assessed by Kaplan-Meier curves with log-rank tests. Subgroup analyses were conducted. Result: A total of 5451 patients were identified in the SEER database. After PSM, the two-year survival among patients who received S, AC, and ACR was 36%, 39%, and 45%, respectively. ACR was associated with improved two-year survival (p < 0.001), while the survival rates were similar in the AC and S groups (p = 0.127) but better in the ACR group than in the AC group (p = 0.012). Subgroup analyses indicated that while the two-year survival rates did not differ significantly in stage II GBC patients between the groups (all p > 0.05), ACR was associated with significantly improved two-year survival in stage Ⅲa (p = 0.008), Ⅲb (p < 0.001), and Ⅳb (p < 0.001) GBC patients. Conclusion: The combination of surgery and ACR as the treatment modality provided greater survival benefits for GBC patients, particularly for those with advanced tumor staging.

19.
Talanta ; 259: 124502, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37027935

RESUMEN

Ag dendrites have recently been widely reported due to their excellent surface-enhanced Raman scattering (SERS) properties. However, prepared pristine Ag dendrites are usually contaminated by organic impurities, which has a huge negative impact on their Raman detection and greatly limits their practical applications. In this paper, we reported a facile strategy to obtain clean Ag dendrites by high temperature decomposition of organic impurities. With the assistance of ultra-thin coating via atomic layer deposition (ALD), the nanostructure of Ag dendrites can be retained at high temperature. SERS activity can be recovered after etching ALD coating. Chemical composition tests indicate that the organic impurities can be effectively removed. As a result, the clean Ag dendrites can obtain more clearly discernible Raman peaks and lower limits of detection than the pristine Ag dendrites. Furthermore, it was demonstrated that this strategy is also applicable to clean other substrates, such as gold nanoparticles. Therefore, high temperature annealing with the help of ALD sacrifice coating is a promising and non-destructive strategy to clean the SERS substrates.

20.
Opt Lett ; 37(9): 1424-6, 2012 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-22555692

RESUMEN

We proposed a novel two-dimensional photonic crystal slab comprised of a number of silicon rods with different radii and locations in the square-lattice unit cell pattern. Such rod-type photonic crystal slabs were automatically optimized by the genetic algorithm and fabricated on the silicon-on-insulator wafer. In particular, the measured transmission spectra of the five-rods sample have shown a large accepted high-order bandgap between 1498 and 1648 nm (gap size is 9.54%). Based on the theories of multiple Bragg and Mie scattering effects, we have given a reasonable explanation to the large high-order bandgaps found in the present study.

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