Simultaneous realization of high gain and low DMG of four-mode EDFA under bidirectional hybrid-mode pump.

We theoretically and experimentally verify that, the bidirectional hybrid-mode pumping scheme can address the optimization problem of trade-off between high gain and low differential modal gain (DMG) of four-mode erbium-doped fiber amplifier (4M-EDFA), in comparison with traditional both forward and backward hybrid-mode pumping scheme. It is noticed that, when the total pump power is fixed, the bidirectional hybrid-mode pumping scheme can not only achieve higher gain, but also suppress DMG due to different overlap integrals for the forward and backward pumping schemes. The bidirectional hybrid-mode pumped 4M-EDFA is developed with the forward pumping at LP02 mode and the backward pumping at LP21 mode, under a pump power ratio of 30%:70%. Thus, we can achieve an average gain of up to 21.16 dB and a low DMG of 0.43 dB at 1550 nm, and an average gain of up to 20.64 dB with a DMG of less than 1.6 dB over the C-band. In particular, the bidirectional hybrid-mode pumping scheme allows us to tailor the gain characteristics of the few-mode erbium-doped fiber amplifiers (FM-EDFAs), by adjusting the power ratio between forward and backward pumps.

Tumor budding is an optimal indictor of occult cervical metastasis in clinical early-stage buccal mucosa squamous cell carcinoma.

BACKGROUND: Buccal mucosa squamous cell carcinoma (BMSCC) is an aggressive disease. This study investigated the clinicopathological significance of tumor budding (TB), depth of invasion (DOI), and mode of invasion (MOI) on occult cervical metastasis (CM) of BMSCC. METHODS: Seventy-one cT1-2N0 BMSCC patients were included in this retrospective study. TB, DOI, MOI, and other clinicopathological features were reviewed. Risk factors for occult CM, locoregional recurrence-free survival (LRRFS), and overall survival (OS) were analyzed using logistic regression and Cox's proportional hazard models, respectively. RESULTS: Multivariate analysis with the logistic regression model revealed that MOI, DOI, and TB were significantly associated with occult CM in early-stage BMSCC after adjusting for variates. However, multivariate analysis with the Cox's proportional hazard model found only TB to be a prognostic factor for LRRFS (hazard ratio 15.03, 95% confidence interval [CI] 1.94-116.66; p = 0.01; trend test p = 0.03). No significant association was found between MOI, DOI, or TB and OS. CONCLUSIONS: The optimal predictor of occult CM and prognosis of early-stage BMSCC is TB, which may assist clinicians in identifying patients at high risk of cervical metastasis.

Plasmonic-induced absorption based on an end-coupled combined resonance system of a semiannular cavity and rectangular cavity.

A semiannular rectangular composite cavity structure based on metal-insulator-metal waveguides is proposed. By adding a rectangular cavity at a suitable position around the semiannular cavity (SAC), a single analogous plasmonic-induced absorption (PIA) effect is achieved at the expected mode of the SAC structure. After adding two rectangular cavities together in the SAC system, dual analogous PIA effects for both modes can be realized simultaneously. In addition, the phase response is also studied, and abnormal dispersions are achieved in the PIA windows, which can be used in the integrated optics for fast/slow light. The performances of the proposed two-dimensional structure are analyzed and studied by the coupled-mode theory and the finite-difference time-domain method, respectively.

Refractive index sensor based on multiple Fano resonances in a plasmonic MIM structure.

A chip-scale refractive index sensor based on multiple Fano resonances is proposed by using a metal-insulator-metal (MIM) structure, which is constructed by two side-coupled semi-ring cavities and a vertical cavity. The finite-difference time-domain method and multimode interference coupled-mode theory are employed to simulate and analyze the transmission spectra of this structure, respectively. First, dual Fano resonances are generated in the MIM structure with a baffle and a semi-ring cavity. By arranging two additional cavities, the mode interferences successfully induce up to six ultra-sharp and asymmetrical Fano peaks. The calculated sensing performances are available with ultra-high sensitivity of 1405 nm/RIU and figure of merit of 3.62×105. This chip-scale refractive index sensor may have great applications in highly integrated photonic circuits.

Plasmonic filter and sensor based on a subwavelength end-coupled hexagonal resonator.

In this paper, an end-coupled hexagonal resonator inserted with dual parallel metallic blocks is proposed based on subwavelength metal-insulator-metal waveguides. When the blocks are vertically inserted into the resonator, more transmission channels (three peaks) with symmetrical spectral shapes than that (one peak) of the perfect hexagonal resonator are achieved in the same wavelength range. The transmission peaks all have high transmittances; thus, the structure can be performed as an on-chip optical filter. When the blocks are horizontally distributed in the resonator, the antinode and node of the magnetic field for the expected mode will arise inside and outside the blocks, leading to the mode interactions. Subsequently, Fano resonance with an asymmetrical peak is achieved in the structure. High index sensitivity and high figure of merit, which are significant factors for optical sensors, are investigated by using the finite-difference time-domain method. The proposed structure can highly support the development of integrated photonics and find wide applications in the on-chip optical filtering and sensing areas.

A Plasmonic Chip-Scale Refractive Index Sensor Design Based on Multiple Fano Resonances.

In this paper, multiple Fano resonances preferred in the refractive index sensing area are achieved based on sub-wavelength metal-insulator-metal (MIM) waveguides. Two slot cavities, which are placed between or above the MIM waveguides, can support the bright modes or the dark modes, respectively. Owing to the mode interferences, dual Fano resonances with obvious asymmetrical spectral responses are achieved. High sensitivity and high figure of merit are investigated by using the finite-difference time-domain (FDTD) method. In view of the development of chip-scale integrated photonics, two extra slot cavities are successively added to the structure, and consequently, three and four ultra-sharp Fano peaks with considerable performances are obtained, respectively. It is believed that this proposed structure can find important applications in the on-chip optical sensing and optical communication areas.

Plasmonic Multichannel Refractive Index Sensor Based on Subwavelength Tangent-Ring Metal⁻Insulator⁻Metal Waveguide.

In this paper, a multichannel refractive index sensor based on a subwavelength metal⁻insulator⁻metal (MIM) waveguide coupled with tangent-ring resonators is proposed. When two tangent-ring resonators were placed above the MIM waveguide, Fano resonance with asymmetrical line shape appeared in the transmission spectrum due to the interference between the light⁻dark resonant modes. The sensitivity and figure of merit were as high as 880 nm/RIU and 964, respectively. Through adding more tangent-ring resonators, multiple Fano resonances with ultrasharp peaks/dips were achieved in the wavelength range of 800⁻2000 nm. Besides, negative group delays were also observed in the Fano resonant dips. Two-dimensional finite-difference time-domain (FDTD) method was used to simulate and analyze the performances of the proposed structures. These kinds of multiring structures can find important applications in the on-chip optical sensing and optical communication areas.

Association between exposure to multiple polyaromatic hydrocarbons and periodontitis: findings from a cross-sectional study.

The impact of environmental pollutant exposure on periodontitis has raised significant concerns. But the association between exposure to multiple polyaromatic hydrocarbons (PAHs) and periodontitis still remained unclear. Our study investigated the association of exposure to multiple PAHs with periodontitis. A total of 1880 participants from the National Health and Nutrition Examination Survey (NHANES) were included in this study. Urinary samples of the participants exposed to six PAHs, namely, 1-hydroxynaphthalene (1-OHN), 2-hydroxynaphthalene (2-OHN), 3-hydroxyfluorene (3-OHF), 2-hydroxyfluorene (2-OHF), 1-hydroxyphenanthrene (1-OHPhe), and 1-hydroxypyrene (1-OHPyr), were investigated. Multiple logistic regression, restricted cubic spline, and Bayesian kernel machine regression (BKMR) models were employed to identify the association between PAH exposures and periodontitis. The dose-response analysis exhibited a gradual increase in the periodontitis risk with an increase in multiple PAHs. After adjustment for several potential confounders, the odds ratio of the highest quartile (Quartile 4) was 1.648 (95% confidence interval (CI) 1.108-2.456, P = 0.014, P-t = 0.017) for 2-OHN, 2.046 (95%CI 1.352-3.104, P < 0.001, P-t = 0.005) for 3-OHF, 1.996 (95% CI 1.310-3.046, P = 0.001, P-t = 0.003) for 2-OHF, 1.789 (95% CI 1.230-2.604, P = 0.002, P-t = 0.003) for 1-OHPhe, and 1.494 (95% CI 1.025-2.181, P = 0.037, P-t = 0.021) for 1-OHPyr compared with that of the lowest quartile (Quartile 1). BKMR illustrated that the overall effect of the PAH mixture was positively related to periodontitis. Mediation analysis identified blood neutrophils as a partial mediator of 3-OHF and 2-OHF. Exposure to multiple PAHs was positively associated with periodontitis in US adults, and blood neutrophils mediate the effects of 3-OHF and 2-OHF therein.

Mandible reconstruction with free fibula flaps: Accuracy of a cost-effective modified semicomputer-assisted surgery compared with computer-assisted surgery - A retrospective study.

A new individualized, cost-effective, modified semi-computer-assisted surgery (MSCAS) concept for free fibular flap mandibular reconstruction is reported and compared with the computer-assisted surgery (CAS) concept. Patients were divided into two groups and retrospectively reviewed. In the MSCAS and CAS groups, intraoperative guides were created using computer-aided design with manual fabrication and computer-aided design and manufacturing, respectively. Differences in specific linear and angular parameters on pre- and postoperative computed tomography scans were calculated for morphometric comparison, and clinical parameters and efficiency were analysed. RESULTS: Eighteen patients (CAS, 7; MSCAS, 11), were included. The morphometric comparison showed no significant differences between the groups. The mean deviation of the mandibular ramus length, body length, width 1 and width 2 was 0.82 ± 0.29 mm, 1.84 ± 0.43 mm, 1.89 ± 0.61 mm and 1.45 ± 0.61 mm in the CAS group versus 1.56 ± 0.54 mm, 1.72 ± 0.33 mm, 2.24 ± 0.55 mm and 2.36 ± 0.50 mm in the MSCAS group (p = 0.7804, p = 0.9997, p = 0.9814 and p = 0.6334). The mean deviation of the sagittal, axial and coronal mandibular angles was 1.56 ± 0.48°, 1.93 ± 0.50° and 2.15 ± 0.72° in the CAS group versus 2.19 ± 0.35°, 1.86 ± 0.35° and 1.94 ± 0.55° in the MSCAS group (p = 0.7594, p = 0.9996 and p = 0.9871). There were no significant differences in clinical parameters, efficiency or postoperative complications between the groups. CONCLUSION: The accuracy and operative efficiency of the MSCAS concept are comparable to those of the more expensive CAS concept. Therefore, in times of increasing clinical costs, this concept might be an adequate and inexpensive alternative to preoperative CAS.

Case Report: Superficial Circumflex Iliac Artery Perforator Flap for Tongue Reconstruction Following the Hemiglossectomy.

Objective: Therapeutic evaluation of applying superficial circumflex iliac artery perforator (SCIP) flap in tongue reconstruction after hemiglossectomy. Methods: We retrospectively collected a total number of 14 patients who received SCIP flap reconstruction for tongue defects at the Fujian Medical University affiliated Union Hospital, between November 2016 and November 2020. We evaluated the clinical features of the flap, analyzed the postoperative functions and esthetic effects after 6 months of the tongue reconstruction. Results: All the SCIP flaps survived successfully after the operation, the recipient site tongue bodies were well reconstructed 6 months after the surgery. Patient speech and swallowing functions were well recovered during the follow-up. The scars in the donor site were concealed with limited numbness. Conclusions: With the advantages of the hidden donor site and aesthetic benefits, the SCIP flap is a reliable option for the reconstruction of the tongue defect after hemiglossectomy.

Study of As2O3 regulating proliferation and apoptosis of Tca8113 cells by inhibiting the expression of Id-1.

OBJECTIVE: Our study aims to investigate the effect of arsenic trioxide (As2O3) on proliferation and apoptosis of Tca8113 tongue squamous carcinoma cells. METHODS: Cell proliferation and the expression of Id-1 mRNA in Tca8113 cells after treatment with different concentrations of As2O3 were detected by MTT and qRT-PCR, respectively. The expression of Id-1, cell proliferation and apoptosis in Id-1 silencing Tca8113 cells were detected by qRT-PCR, Western blot, MTT and flow cytometry, respectively. The pcDNA 3.1-Id-1 overexpression vector was transfected into Tca8113 cells combination with 3 µmol/L As2O3. The detection of cell proliferation, apoptosis and Caspase-3, Bax and Bcl-2 protein expression in transfected Tca8113 cells were performed by MTT, flow cytometry and Western blot assay, respectively. RESULTS: As2O3 of different concentration could inhibit the proliferation of Tca8113 cells and IC50 value was 3.004 ± 0.2379 µmol/L. The expression of Id-1 mRNA was down-regulated in Tca8113 cells treated with 3 µmol/L As2O3 for 48 h. The results of qRT-PCR, Western blot, MTT and flow cytometry indicated that the expression level of Id-1 and cell proliferation ability were decreased while the apoptosis rate was increased in Tca8113 cells after transfection of Id-1 siRNA. Overexpression of Id-1 could attenuate the inhibition or promotion of As2O3 on proliferation, apoptosis and Caspase-3, Bax and Bcl-2 protein expression in Tca8113 cells. CONCLUSION: As2O3 could regulate the proliferation and apoptosis of Tca8113 cells by inhibiting the expression of Id-1.

Reducing depressive or anxiety symptoms in post-stroke patients: Pilot trial of a constructive integrative psychosocial intervention.

BACKGROUND: About 30% of stroke survivors clinically have depressive symptoms at some point following stroke and anxiety prevalence is around 20-25%. OBJECTIVE: The purpose of this brief report is to evaluate a pilot trial of a constructive integrative psychosocial intervention (CIPI) over standard care in post-stroke depression or anxiety. METHODS: Patients were randomly assigned to either CIPI (n = 23) or standard care (n = 19). Patients were assessed using the Hospital Anxiety and Depression Scale at the 1st, 3rd, and 6th months to monitor changes of mood. RESULTS: A Wilcoxon signed-rank test indicated that compared to admission baseline, patients with the intervention had significantly normal post-stroke depression symptom levels at the 1st, 3rd, and 6th months (P < 0.005). CONCLUSION: CIPI appears to be of incremental value in treating depression as well as anxiety in subacute care.