Multitask Learning Deep Neural Networks Enable Embedded Design of Active Metamaterials

In this study, we propose and implement a deep neural network framework based on multitask learning aimed at simplifying the forward modeling and inverse design process of photonic devices integrating active metasurfaces. We demonstrate and validate our approach by constructing a continuously tunable bandpass filter that is effective in the midwave infrared region. The key to this filter is the combination of a metasurface and Fabry-Perot (F-P) cavity structure of the tunable phase-change material Ge2Sb2Se4Te (GSST) and the precise control of the crystallinity of the GSST by a silicon-based heater. With the help of a deep learning framework, we are able to independently model the crystallinity and geometric parameters of the filter to maximize the use of GSST tuning for bandpass filtering. Our model discusses the self-attention mechanism and the effect of noise and compares several existing popular algorithms, and the results show that a multitask deep learning strategy can better assist the on-demand reverse design of photonic structures with phase change materials. This opens up new possibilities for personalization and functional extension of optical devices.

Two-photon fluorescence-guided precise photothermal therapy located in a single cancer cell utilizing bifunctional N-doped carbon quantum dots

The utilization of carbon quantum dots (CQDs) for photothermal therapy has emerged as a hot research topic. However, there has been limited research on killing one single cancer cell which is critical in reducing unnecessary damage to the surrounding healthy tissues. In this work, we developed a two-photon fluorescence-guided precise photothermal therapy in a single human malignant melanoma (A375) cancer cell utilizing bifunctional N-doped CQDs. Resulting from the two-photon fluorescence of the CQDs, one single cancer cell can be located and simultaneously destroyed by the photothermal effect of the same CQDs. Specifically, the balanced two-photon absorption cross-section (7000 GM) and photoluminescence quantum yield (8.4%) of the CQDs enable the fluorescence-guided photothermal treatment to be achieved in only 5 s under the irradiation of 800 nm laser of 27.5 mW, much faster than the control experiment without the guidance of fluorescence. The heat generated by the aggregated CQDs is in sufficient amounts while being confined in a small area, as evidenced by the numerical simulations and photothermal experiments, to limit the range of thermal treatment in the cells. This work provides a new approach for realizing photothermal therapy with minimal damage and establishes a new application scenario of CQDs for precise tumor ablation.

[α2-macroglobulin alleviates glucocorticoid-induced avascular necrosis of the femoral head in mice by promoting proliferation, migration and angiogenesis of vascular endothelial cells]

OBJECTIVE

To explore the mechanism underlying the protective effect of α2-macroglobulin (A2M) against glucocorticoid-induced femoral head necrosis.

METHODS

In a human umbilical vein endothelial cell (HUVEC) model with injuries induced by gradient concentrations of dexamethasone (DEX; 10-8-10-5 mol/L), the protective effects of A2M at 0.05 and 0.1 mg/mL were assessed by examining the changes in cell viability, migration, and capacity of angiogenesis using CCK-8 assay, Transwell and scratch healing assays and angiogenesis assay. The expressions of CD31 and VEGF-A proteins in the treated cells were detected using Western blotting. In BALB/c mouse models of avascular necrosis of the femoral head induced by intramuscular injections of methylprednisolone, the effects of intervention with A2M on femoral trabecular structure, histopathological characteristics, and CD31 expression were examined with Micro-CT, HE staining and immunohistochemical staining.

RESULTS

In cultured HUVECs, DEX treatment significantly reduced cell viability, migration and angiogenic ability in a concentration- and time-dependent manner (P<0.05), and these changes were obviously reversed by treatment with A2M in positive correlation with A2M concentration (P<0.05). DEX significantly reduced the expression of CD31 and VEGF-A proteins in HUVECs, while treatment with A2M restored CD31 and VEGF-A expressions in the cells (P<0.05). The mouse models of femoral head necrosis showed obvious trabecular damages in the femoral head, where a large number of empty lacunae and hypertrophic fat cells could be seen and CD31 expression was significantly decreased (P<0.05). A2M treatment of the mouse models significantly improved trabecular damages, maintained normal bone tissue structures, and increased CD31 expression in the femoral head (P<0.05).

CONCLUSION

A2M promotes proliferation, migration, and angiogenesis of DEX-treated HUVECs and alleviates methylprednisolone-induced femoral head necrosis by improving microcirculation damages and maintaining microcirculation stability in the femoral head.

Strain-insensitive micro torsion and temperature sensor based on a helical taper seven-core fiber structure

We propose a multimode interference-based optical fiber NHTSN sensor with a helical taper for simultaneous measurement of micro torsion and temperature. The sensor consists of single mode fiber (SMF), no-core fiber (NCF), and seven-core fiber (SCF). A helical taper is fabricated in the SCF using a flame heater, forming the SMF-NCF-Helical Taper SCF-NCF-SMF (NHTSN) structure. Theoretical analysis and experimental results demonstrate that the introduction of helical taper not only imparts directionality to the torsion measurement, but also results in a significant improvement in torsion sensitivity due to the increased inter-mode optical path difference (OPD) and enhanced inter-mode coupling. In the experiment, the torsion sensitivity of the NHTSN sensor reaches -1.255 nm/(rad/m) in the twist rate (TR) range of -3.931 rad/m to 3.931 rad/m, which is a 9-fold improvement over the original structure. Further reduction of the helical taper diameter increases the sensitivity to -1.690 nm/(rad/m). In addition, the sensor has a temperature sensitivity of up to 97 pm/°C from 20 °C to 90 °C, and simultaneous measurement of torsion and temperature is attainable through a dual-parameter measurement matrix. The NHTSN sensor possesses advantages of compact size, high sensitivity, good linearity, and strain-independence, endowing it with potential applications in structural health monitoring (SHM) and engineering machinery.

Neutron-gamma discrimination with broaden the lower limit of energy threshold using BP neural network

Neutron-gamma discrimination is a tough and significative in experimental neutrons measurements procedure, especially for low-energy neutrons signal discrimination. In this work, based on the Pulse Shape Discrimination (PSD) and Back-Propagation (BP) artificial neural networks, a neutron-gamma discrimination method is developed to broaden the lower limit of energy threshold with the hidden layer of 20 neurons. Compared with neutron-gamma discrimination method based on PSD only, the developed neutron-gamma discrimination method based on the PSD and BP-ANN can discriminate neutron and gamma-ray signals with low energy threshold, which can discriminate signals up to 99.93%. Moreover, this work can reduce the energy threshold from 350 keV to 70 keV, as well as the acquired data utilization increased from 60% to more than 99.9%, which overcome the hardware limitations and distinguish neutron and gamma-ray signals, effectively. The developed neutron-gamma discrimination method and the trained neural network can be directly used to other experimental neutrons measurements.

[Effect of HCMV infection on immune reconstitution of CD8+T cells in children with allogeneic hematopoietic stem cell transplantation]

Objective: To investigate the risk factors for human cytomegalovirus infection after allogeneic hematopoietic stem cell transplantation in children and the impact of human cytomegalovirus infection on post-transplant immune reconstitution. Methods: A Retrospective Co-Hort study design was used to include 81 children treated with allo-HSCT from January 2020 to March 2022 at the Department of Hematology, Capital Institute of Pediatrics, Beijing, China, and followed up for 1 year. Real-time quantitative PCR was used to detect positive detection of HCMV in children after allo-HSCT, multifactorial logistic regression modeling was used to analyze the risk factors leading to HCMV infection, and generalized estimating equation modeling was used to analyze the effect of HCMV infection on the T-cells of the children who received allo-HSCT. Results: The age M(Q1, Q3) of 81 children was 5.1 years (10 months, 13.8 years), and 50 (61.7%) were male. By the endpoint of follow-up, a total of 50 HCMV-positive cases were detected, with an HCMV detection rate of 61.7%; The results of multifactorial logistic regression modeling showed that children with grade 2-4 aGVHD had a higher risk of HCMV infection compared with grade 0-1 after transplantation [OR (95%CI) value: 2.735 (1.027-7.286)]. The results of generalized estimating equation modeling analysis showed that the number of CD3+T cells in HCMV-positive children after transplantation was higher than that in the HCMV-negative group [RR (95%CI) value: 1.34 (1.008-1.795)]; the ratio of CD4+T/CD8+T cells was smaller than that in the HCMV-negative group [RR (95%CI) value: 0.377 (0.202-0.704)]; the number of CD8+T cells was higher than that in the HCMV-negative group [RR (95%CI) value: 1.435 (1.025-2.061)]; the number of effector memory CD8+T cells was higher than that in the HCMV-negative group [RR (95%CI) value: 1.877 (1.089-3.236)]. Conclusion: Acute graft-versus-host disease may be a risk factor for HCMV infection in children after allo-HSCT; post-transplant HCMV infection promotes proliferation of memory CD8+T-cell populations and affects immune cell reconstitution.

Morin protects chicks with T-2 toxin poisoning by decreasing heterophil extracellular traps, oxidative stress and inflammatory response

1. Fusarium tritici widely exists in a variety of grain feeds. The T-2 toxin is the main hazardous component produced by Fusarium tritici, making a serious hazard to poultry industry. Morin, belonging to the flavonoid family, can be extracted from mulberry plants and possesses anticancer, antioxidant and anti-inflammatory compounds, but whether morin protects chicks with T-2 toxin poisoning remains unclear. This experiment firstly established a chick model of T-2 toxin poisoning and then investigated the protective effects and mechanism of morin against T-2 toxin in chicks.2. The function of liver and kidney was measured by corresponding alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), blood urea nitrogen (BUN), creatinine (Cre) and uric acid (UA) kits. Histopathological changes were observed by haematoxylin-eosin staining. The status of oxidative stress was measured by MDA, SOD, CAT, GSH and GSH-PX kits. The mRNA levels of TNF-α, COX-2, IL-1β, IL-6, caspase-1, caspase-3 and caspase-11 were measured by quantitative real-time PCR. Heterophil extracellular trap (HET) release was analysed by immunofluorescence and fluorescence microplate.3. The model with T-2 toxin poisoning in chicks was successfully established. Morin significantly decreased T-2 toxin-induced ALT, AST, ALP, BUN, Cre and UA, and improved T-2 toxin-induced liver cell rupture, liver cord disorder and kidney interstitial oedema. Oxidative stress analysis showed that morin ameliorated T-2 toxin-induced damage by reducing malondialdehyde (MDA), increasing superoxide dismutase (SOD), catalase (CAT), glutathione (GSH) and glutathione peroxidase (GSH-PX). The qRT-PCR analysis showed that morin reduced T-2 toxin-induced mRNA expressions of TNF-α, COX-2, IL-1β, IL-6, caspase-1, caspase-3 and caspase-11. Moreover, morin significantly reduced the release of T-2 toxin-induced HET in vitro and in vivo.4. Morin can protect chicks from T-2 toxin poisoning by decreasing HETs, oxidative stress and inflammatory responses, which make it a useful compound against T-2 toxin poisoning in poultry feed.

Automated Contouring of Cervical Lymph Nodes and Clinical Target Volumes for Nasopharyngeal Carcinoma Based on Deep Learning and Experience Constraints

PURPOSE/OBJECTIVE(S)

Application of artificial intelligence (AI) for automated contouring of tumor volumes and organs at risk (OARs) for radiotherapy of nasopharyngeal carcinoma (NPC) leads to improved contouring accuracy and efficiency. However, few studies have involved the automated contouring of gross tumor volume of cervical lymph nodes (GTVn) and clinical target volumes (CTVs). In this work, we proposed an AI automated contouring tool for GTVn and CTVs for radiotherapy of NPC on the plain scans of planning compute tomography (CT).

MATERIALS/METHODS

In this retrospective study, plain scan datasets of planning CT covering the nasopharynx and neck from 139 patients with NPC between March 2022 and December 2022 were collected and divided into training, validation, and testing cohorts of 95, 24, and 20 patients, respectively. Ground truth contours of primary gross tumor volume (GTVp), GTVn (divided into GTVn_L in left neck and GTVn_R in right neck), CTVs (including high risk CTV1 contains GTVp and low risk CTV2 contains GTVp and cervical nodal levels) and OARs were delineated and were defined by consensus of two experts. We first proposed a three-dimensional (3D) U-net using GTVp and OARs as experience constrains to guide the automated delineation of GTVn and CTVs. The average Dice similarity coefficient (DSC) and average surface distance (ASD) were used to quantify the performance of the AI tool. Next, five prospective patients were enrolled for clinical evaluation of our AI tool. DSC between automated contours and radiation oncologist-revised contours and time consuming of the revision were record.

RESULTS

Clinical characteristics of 139 retrospective and 5 prospective patients are list in Table 1. In the independent testing set of 20 patients, our AI tool showed high performance in GTVn and CTVs contouring when compared with the ground truth contours. The mean DSC were 0.73 ± 0.07, 0.74 ± 0.05, 0.93 ± 0.03, and 0.88 ± 0.03, and the mean ASD were 1.01 ± 0.43 mm, 1.14 ± 0.61 mm, 0.51 ± 0.13 mm, 1.17 ± 0.43 mm for GTVn_L, GTVn_R, CTV1 and CTV2, respectively. In the five prospective patients, mean DSC were 0.74 ± 0.07, 0.74 ± 0.10, 0.95 ± 0.01 and 0.89 ± 0.04, respectively. The median time consuming for GTVn and CTVs revision was 2minutes and 10 seconds (range, 1 minutes to 3 minutes).

CONCLUSION

The proposed AI tool integrating clinical experience as constrains showed high accuracy for contouring GTVn and CTVs of NPC. With the assistance of AI contours, contouring efficiency could be probably increased, which is promising in online adaptive radiotherapy of NPC.

Singular multi-wavelength and multi-waveband transparencies generated by P T-symmetric dumbbell optical waveguide networks

In this paper, we investigate the singular multi-wavelength and multi-waveband transparencies generated by P T-symmetric dumbbell optical waveguide networks composed of two materials, and obtain the number regularity for the transparency wavelengths of one-unit-cell system and the general relationships for the transmission and reflection coefficients of multi-unit-cell systems. Consequently, three types of exact transparencies produced by multi-unit-cell systems are found based on the aforementioned formulas: (i)exact multi-wavelength unidirectional or bidirectional transparency as the same as those of one-unit-cell system; (ii)exact multi-wavelength bidirectional transparency at which one-unit-cell system cannot produce exact transparency, generated by adjusting the number of unit cells; (iii)exact multi-wavelength bidirectional transparency at which one-unit-cell system produces exact transparency, also generated by adjusting the number of unit cells. It provides theoretical foundations for developing highly sensitive and multi-wavelength optical filters. On the other hand, we also discover that multi-unit-cell systems can create approximate multi-waveband bidirectional transparencies by adjusting the number of unit cells, which provides scientific support for developing high-performance optical stealth devices.

[Preventive effect of atropine premedication on vagal reflex in patients undergoing suspension laryngoscopy during anesthesia induction]

Objective: To evaluate the preventive effect of atropine premedication during anesthesia induction on vagal reflex in patients undergoing suspension laryngoscopy. Methods: A total of 342 patients (202 males and 140 females) scheduled for suspension laryngoscopy under general anesthesia in Beijing Tongren Hospital from October 2021 to March 2022 were prospectively enrolled, with a mean age of (48.1±11.9) years. The patients were randomly divided into two groups using the random number table method: the treatment group (n=171) and the control group (n=171). Patients in the treatment group were administrated with 0.5 mg atropine intravenously guttae (ivgtt) while patients in the control group were given equivalent volume of normal saline. For all patients, if heart rate (HR)<50 beats/min happened during the insertion of the suspension laryngoscope, the operation should be stopped and the laryngoscope should be removed. Patients without HR recovery after the removal of the laryngoscope should be given 0.5 mg atropine, and the operation should be continued after the HR recovered. The primary outcome was the incidence of HR fluctuation over 20% (ΔHR>20%) before and immediately after suspension laryngoscope fixation, and the secondary outcomes included HR, mean arterial pressure (MAP) of the two groups recorded before and after anesthesia induction, before and immediately after suspension laryngoscope fixation, and the incidences of sinus bradycardia, laryngoscope removal and atropine treatment during operation. Results: The incidences of ΔHR>20% and bradycardia immediately after the suspension laryngoscope fixation were 14.6% (25/171) and 12.9% (22/171) in the treatment group, which were significantly lower than those in the control group [28.1% (48/171) and 29.8% (51/171)] (both P<0.05). The HR immediately after the suspension laryngoscope fixation in the treatment group [(66.4±13.5) beats/min] and in the control group [(60.8±15.7) beats/min] was significantly lower than those before the suspension laryngoscope fixation [(74.7±11.1) beats/min and (67.6±12.8) beats/min, respectively] (both P<0.05). There were no significant differences in MAP between the two groups at each time point (all P>0.05). The incidence of laryngoscope removal once plus 0.5 mg atropine administration, laryngoscope removal twice plus 0.5 mg atropine administration and laryngoscope removal twice plus 1.0 mg atropine administration was 9.9% (17/171), 1.8% (3/171) and 0 (0) in the treatment group, respectively, which was significantly lower than those in the control group [24.0% (41/171), 5.8% (10/171) and 2.3% (4/171), respectively] (all P<0.05). Conclusion: Atropine premedication during anesthesia induction can effectively reduce the occurrence of vagal reflex in patients undergoing suspension laryngoscopy.

Three-Channel Near-Field Display and Encryption Based on a Polarization Multiplexed Metasurface

Multichannel metasurfaces are becoming a significant trend in the field of optical encryption due to their excellent manipulation of optical wavefronts. However, existent multichannel metasurfaces for optical encryption mostly implement only two channels in the near-field, or three channels by combining the near- and far-field. In this paper, we propose and simulate a three-channel metasurface that works entirely in the near-field and uses the polarization state of the incident light, left circularly polarized (LCP) light, right circularly polarized (RCP) light, and linearly polarized (LP) light as the security key. The metasurface consists of two types of nanostructures that work as a polarizer and a quarter-wave plate, providing an additional degree of freedom for encoding that enables independent near-field display at 633 nm wavelength incident light. The proposed three-channel metasurface has the advantages of high information density and high security, which will pave the way for multi-channel applications such as ultracompact displays, optical encryption, and information storage.

Generation and measurement of irregular polygonal perfect vortex optical beam based on all-dielectric geometric metasurface

The perfect optical vortex (POV) beam carrying orbital angular momentum with topological charge-independent radial intensity distribution possesses ubiquitous applications in optical communication, particle manipulation, and quantum optics. But the mode distribution of conventional POV beam is relatively single, limiting the modulation of the particles. Here, we originally introduce the high-order cross-phase (HOCP) and ellipticity γ into the POV beam and construct all-dielectric geometric metasurfaces to generate irregular polygonal perfect optical vortex (IPPOV) beams following the trend of miniaturization and integration of optical systems. By controlling the order of the HOCP, conversion rate u, and ellipticity factor γ, various shapes of IPPOV beams with different electric field intensity distributions can be realized. In addition, we analyze the propagation characteristics of IPPOV beams in free-space, and the number and rotation direction of bright spots at the focal plane give the magnitude and sign of the topological charge carried by the beam. The method does not require cumbersome devices or complex calculation process, and provides a simple and effective method for simultaneous polygon shaping and topological charge measurement. This work further improves the beam manipulation ability while maintaining the characteristics of the POV beam, enriches the mode distribution of the POV beam, and provides more possibilities for particle manipulation.

Robotic versus laparoscopic left colectomy with complete mesocolic excision for left-sided colon cancer: a multicentre study with propensity score matching analysis

BACKGROUND

Robotic surgery for right-sided colon and rectal cancer has rapidly increased; however, there is limited evidence in the literature of advantages of robotic left colectomy (RLC) for left-sided colon cancer. The purpose of this study was to compare the outcomes of RLC versus laparoscopic left colectomy (LLC) with complete mesocolic excision (CME) for left-sided colon cancer.

METHODS

Patients who had RLC or LLC with CME for left-sided colon cancer at 5 hospitals in China between January 2014 and April 2022 were included. A one-to-one propensity score matched analysis was performed to decrease confounding. The primary outcome was postoperative complications occurring within 30 days of surgery. Secondary outcomes were disease-free survival, overall survival and the number of harvested lymph nodes.

RESULTS

A total of 292 patients (187 males; median age 61.0 [20.0-85.0] years) were eligible for this study, and propensity score matching yielded 102 patients in each group. The clinical-pathological characteristics were well-matched between groups. The two groups did not differ in estimated blood loss, conversion to open rate, time to first flatus, reoperation rate, or postoperative length of hospital stay (p > 0.05). RLC was associated with a longer operation time (192.9 ± 53.2 vs. 168.9 ± 52.8 minutes, p=0.001). The incidence of postoperative complications did not differ between the RLC and LLC groups (18.6% vs. 17.6%, p = 0.856). The total number of lymph nodes harvested in the RLC group was higher than that in the LLC group (15.7 ± 8.3 vs. 12.1 ± 5.9, p< 0.001). There were no significant differences in 3-year and 5-year overall survival or 3-year and 5-year disease-free survival.

CONCLUSIONS

Compared to laparoscopic surgery, RLC with CME for left-sided colon cancer was found to be associated with higher numbers of lymph nodes harvested and similar postoperative complications and long-term survival outcomes.

Numerical Simulation of Integrated Generation and Shaping of Airy and Bessel Vortex Beams Based on All-Dielectric Metasurface

Integrating multiple independent functions into a single optical component is one of the most important topics in research on photoelectric systems. In this paper, we propose a multifunctional all-dielectric metasurface that can achieve a variety of non-diffractive beams depending on the polarization state of the incident light. Using the anisotropic TiO₂ rectangular column as the unit structure, the three functions of generating polygonal Bessel vortex beams under left-handed circularly polarized incidence, Airy vortex beams under right-handed circularly polarized incidence and polygonal Airy vortex-like beams under linearly polarized incidence are realized. In addition, the number of polygonal beam sides and the position of focal plane can be adjusted. The device could facilitate further developments in scaling complex integrated optical systems and fabricating efficient multifunctional components.

Highly localized, efficient, and rapid photothermal therapy using gold nanobipyramids for liver cancer cells triggered by femtosecond laser

In this study, the photothermal effect and up-conversion florescence imaging effect of gold nanobipyramids in liver cancer cells are investigated theoretically and experimentally to explore the photothermal ablation tumor therapy with higher photothermal conversion efficiency, shorter laser action time, smaller action range and lower laser power. The small-size gold nanobipyramids with good biocompatibility and infrared absorption peak located in the first biological window are synthesized. Femtosecond laser is focused on the nanobipyramids clusters in cells and the cells die after being irradiated for 20 s at a power as low as 3 mW. In contrast, the control cells die after irradiation with 30 mW laser for 3 min. The theoretical simulation results show that: under femtosecond laser irradiation, the local thermal effect of gold nanoclusters is produced in the range of hundreds of square nanometers and the temperature rises by 516 °C in 106 picoseconds. This therapy reduces the treatment time to seconds level, and the treatment range to square micrometer level, the power to milliwatt level. In this treatment, cells die by apoptosis rather than necrosis, which reduces inflammation. This result opens up a new way to develop photothermal ablation therapy with less side effects and more minimally invasive.

[Development of parenting behavior scale for caregivers of children aged 2 to 6 years and analysis for its reliability and validity]

To develop a caregiver parenting behavior scale for children aged 2 to 6 years, and to verify its reliability and validity. This study recruited 1 350 caregivers of children aged 2 to 6 years. The item discrimination analysis and exploratory factor analysis were used to analyze the structure, dimensions and items of the scale. Homogeneity reliability, split-half reliability and test-retest reliability were used to analyze the reliability of the scale. Content validity and construct validity were used to analyze the validity of the scale. The results showed that the final scale contained 7 dimensions and 45 items. Cronbach's α coefficient of the total scale was 0.945; the coefficient of split half was 0.899; the test-retest reliability analysis showed that the correlation coefficients between the two tests were 0.893 (total score), 0.854 (social), 0.832 (language), 0.871 (gross motor), 0.893 (fine motor), 0.862 (cognitive), 0.832 (self-care), and 0.872 (sensory). The content validity analysis was carried out by two rounds of expert argumentation using Delphi expert consultation method. The Kendall coefficient of the items score in two rounds of Delphi expert consultation was 0.813 (P<0.01). The structure validity analysis showed that there were significant correlations between each dimension and the total scale, also between each dimension of the scale, and the extracted average variance values of each dimension was greater than the correlation coefficients between this dimension and other dimensions. In conclusion, the reliability and validity of the scale are qualified. It can be used as a tool to evaluate and guide the parenting behavior of caregivers of children aged 2 to 6 years.

Three-Channel Metasurfaces for Multi-Wavelength Holography and Nanoprinting

Metasurfaces, employed to simultaneously generate nanoprinting and holographic images, have been extensively explored recently. Among them, multi-wavelength multiplexing in a single metasurface is often accompanied by dispersion and crosstalk, which hinder the display of multicolor patterns. Here, we propose an efficient phase method to decouple the wavelength and realize a three-channel display operating at different wavelengths. Holographic images appear in the far field with the illumination of two different circularly polarized lights while a nanoprinting image is reconstructed by inserting an orthogonal optical path with the illumination of linear polarization light. The proposed metasurface is only composed of four types of unit cells, which significantly decreases the complexity of fabrication and improves the information capacity. Benefiting from its different decoding strategies and capability of multi-wavelength control, this approach may develop broad applications in information encryption, security, and color display.

Strong enhancement of Goos-Hänchen shift through the resonant optical tunneling effect

The resonant optical tunneling effect (ROTE) originates from the frustrated total reflection effect because unique transmission characteristics are used to study high-sensitivity sensors. In this study, we theoretically demonstrated that choosing a suitable transmission gap made it possible for the ROTE structure based on hexagonal boron nitride and graphene to obtain a large Goos-Hänchen shift as high as tens of thousands of times the incident wavelength at a specific incident angle. The amplitude of the Goos-Hänchen shift was found to be sensitive to the central layer thickness but was also modulated by the tunneling gap on both sides. In addition, adjusting the chemical potential and relaxation time of the graphene sheets could alter the Goos-Hänchen shift. Our work provides a new way to explore the Goos-Hänchen effect and opens the possibility for the application of high-precision measurement technology based on the ROTE.

Asymmetric structure optical fiber humidity sensor assisted by the virtual Vernier effect

In this paper, an asymmetric structure optical fiber sensor is proposed to measure relative humidity (RH). The sensing structure is composed of splicing dispersion compensation fiber (DCF) and coreless fiber (NCF), and two sections of single-mode fiber (SMF) at both ends. Peanut shaped structure is used as a beam splitter at the input side, and the NCF is used as a beam combiner at the output side to form interference fringes. The partial cladding of DCF was etched, and polyvinyl alcohol (PVA) was coated on the etched area to form a hygroscopic film. When the ambient humidity changes, the refractive index and thickness of the hygroscopic film will change, which will lead to the wavelength shift of the resonant dip. The experimental results show that the sensitivity of the sensor is 0.1304 nm/RH% and 0.4452 nm/RH% in the RH range of 55%-75% and 75%-95%, respectively. In order to improve the sensitivity further, the original spectrum data is filtered by fast Fourier transform (FFT) and inverse fast Fourier transform (IFFT), and the high-frequency interference components of high-order mode (LP₀₉) and fundamental mode are obtained, which is superimposed with a simulated signal to form Vernier effect. With the method of virtual Vernier effect, the sensitivity in the RH range of 55%-75% is improved to 2.869 nm/RH%, which is 22 times larger than the original sensitivity, and the sensitivity in the RH range of 75%-95% is improved to 2.64 nm/RH%, which is 6 times larger than the original sensitivity.

Communication wavelength investigation of bound states in the continuum of one-dimensional two-material periodic ring optical waveguide network

In this study, a one-dimensional (1D) two-material period ring optical waveguide network (TMPROWN) was designed, and its optical properties were investigated. The key characteristics observed in the 1D TMPROWN include the following: (1) Bound states in continuum (BICs) can be generated in the optical waveguide network. (2) In contrast to the BICs previously reported in optical structures, the range of the BICs generated by the 1D TMPROWN is not only larger, but also continuous. This feature makes it possible for us to further study the electromagnetic wave characteristics in the range of the BICs. In addition, we analyzed the physical mechanisms of the BICs generated in the 1D TMPROWN. The 1D TMPROWN is simple in structure, demonstrates flexibility with respect to adjusting the frequency band of the BICs, and offers easy measurement of the amplitude and phase of electromagnetic waves. Hence, further research on high-power super luminescent diodes, optical switches, efficient photonic energy storage, and other optical devices based on the 1D TMPROWN designed in this study is likely to have implications in a broad range of applications.

Extraordinary Characteristics of One-Dimensional PT-Symmetric Ring Optical Waveguide Networks Composed of Adjustable Length Ratio Waveguides

A novel one-dimensional parity-time-symmetric periodic ring optical waveguide network (1D PTSPROWN) is constructed using magnesium fluoride (MgF₂), by adjusting the length ratio of gain and loss materials in PT-symmetric waveguide and ordinary dielectric material, and by optimizing the program to search for the extremum spontaneous PT-symmetric breaking points. The ultra-strong transmission, reflection, and photonic location are noticed in the proposed 1DPTSPROWN as compared with the other PT-symmetric optical waveguide networks. The maximum and minimum reached 10¹⁸ and 10^-15, respectively, which is more than 6 orders of magnitude greater and 3 orders of magnitude smaller than the best results reported so far. The ultra-strong transmission and reflection peaks, ultra-weak transmission, and reflection valleys generated by electromagnetic waves in this network were found to have interesting resonance and anti-resonance effects. Furthermore, frequency of periodic cycles and violet or redshift laws were discovered in the 1D PTSPROWN of fixed length ratio of gain and loss material in the PT-symmetric waveguide by adjusting the ratio of the upper and lower arm lengths of waveguides. The proposed optical waveguide network might have potential application in the design of CPA lasers, high-efficiency optical accumulators, and several other devices.

Semen parameters and sex hormones as affected by SARS-CoV-2 infection: A systematic review

Background

Impaired semen quality and reproductive hormone levels were observed in patients during and after recovery from coronavirus disease 2019 (COVID-19), which raised concerns about negative effects on male fertility. Therefore, this study systematically reviews available data on semen parameters and sex hormones in patients with COVID-19.

Methods

Systematic search was performed on PubMed and Google Scholar until July 18th, 2022. We identified relevant articles that discussed the effects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on male fertility.

Results

A total number of 1,684 articles were identified by using a suitable keyword search strategy. After screening, 26 articles were considered eligible for inclusion in this study. These articles included a total of 1,960 controls and 2,106 patients. When all studies were considered, the results showed that the semen parameters and sex hormone levels of patients infected with SARS-CoV-2 exhibited some significant differences compared with controls. Fortunately, these differences gradually disappear as patients recover from COVID-19.

Conclusion

While present data show the negative effects of SARS-CoV-2 infection on male fertility, this does not appear to be long-term. Semen quality and hormone levels will gradually increase to normal as patients recover.

Generation of multi-channel perfect vortex beams with the controllable ring radius and the topological charge based on an all-dielectric transmission metasurface

The perfect vortex (PV) beam, characterized by carrying orbital angular momentum and a radial electric intensity distribution independent of the topological charge, has important applications in optical communication, particle manipulation, and quantum optics. Conventional methods of generating PV beams require a series of bulky optical elements that are tightly collimated with each other, adding to the complexity of optical systems. Here, making the amplitude of transmitted co-polarized and cross-polarized components to be constant, all-dielectric transmission metasurfaces with superimposed phase profiles integrating spiral phase plate, axicon and Fourier lens are constructed based on the phase-only modulation method. Using mathematical derivation and numerical simulation, multi-channel PV beams with controllable annular ring radius and topological charge are realized for the first time under circularly polarized light incidence combining the propagation phase and geometric phase. Meanwhile, perfect vector vortex beams are produced by superposition of PV beams under the incidence of left-handed circularly polarized and right-handed circularly polarized lights, respectively. This work provides a new perspective on generating tailored PV beams, increasing design flexibility and facilitating the construction of compact, integrated, and versatile nanophotonics platforms.

Three-channel metasurface based on simultaneous and independent control of near and far field under a single line light source

Metasurface based on independent and simultaneous control of near field and far field has significant potential for use in multichannel optics platform devices. However, the previous studies cannot satisfy independent and simultaneous control of near field and far field under a single line source, which made a significant challenge to multichannel optical platforms working in a compact environment. To manipulate effectively and freely the amplitude and phase of transmission under line source, Marius' law and Propagation phase was introduced on all-dielectric encoding metasurfaces meta-atoms. The Marius' law and Propagation phase can control the size and rotation angle of meta-atoms to encode grayscale amplitude images and holographic phase images. Finite-difference time-domain simulation results reveal that dual channel metasurface under a single line source achieves the same display effect as the dual channel metasurface under multiple light sources, which proves the feasibility of our studies. Moreover, under different angles of the line source, we encode the near-field binary image by using the degeneracy rotation angle of meta-atoms. Finally, a three-channel metasurface was obtained without affecting the display of the previous two-channel metasurface. As a result, the independent control amplitude, phase, and polarization of the incident light wave were achieved. The proposed metasurface could be applied in creating a multi-channel metasurface optical platform in a compact environment, which has application potential in image displays, optical storage, optical anti-counterfeiting, and information encryption technology.

[Effect of ultrasound-guided serratus plane block combined with pectoral nerve block I on postoperative analgesia after radical mastectomy]

Objective: To study the effect of ultrasonic-guided serratus plane block combined with pectoral nerve block Ⅰ on postoperative analgesia after radical mastectomy. Methods: A total of 30 patients, all female, aged [M (Q₁, Q₃)] 53 (43, 62) years old, who underwent radical mastectomy in Beijing Tongren Hospital from May to August 2021 were selected. The patients were divided into two groups (n=15 in each group) using a random number table: general anesthesia alone+patient controlled intravenous analgesia (PCIA) group (control group) and serratus plane block combined with pectoral nerve block Ⅰ before general anesthesia+PCIA group (combined group). Numerical rating scale (NRS) at rest in both groups were detected in the post anesthesia care unit (PACU) and 4, 8, 12, 24, 36 and 48 h after operation. The time of first pain, the time of first pressing of the automatic analgesic device after the operation, the dosage of remifentanil during operation, cumulative dosages of sufentanil at 24 h and 48 h postoperatively, and the incidence of adverse effects were all recorded. Results: The NRS scores in combined group in the PACU and 4, 8, 12 and 24 h after surgery were (2.1±1.7), (1.7±1.5), (1.5±1.4), (1.5±1.3) and (1.7±1.3), respectively, while the NRS scores in control group at each time points were (4.5±2.0), (3.2±1.4), (2.7±0.9), (2.8±0.9) and (2.4±0.8), respectively, and the NRS scores in combined group were significantly lower than those in control group (all P<0.05). The NRS scores in combined group at 36 and 48 h after surgery were (1.8±1.6) and (1.6±1.2), while the NRS scores in control group were (2.2±0.9) and (2.1±0.8), and the differences between the two groups were not statistically significant (both P>0.05). The time of first pain and the time of the first pressing of the automatic analgesic device in combined group were (573±174) min and (962±313) min, which were significantly longer than those of control group [(13±6) min and (135±41) min] (both P<0.05). The dosage of remifentanil during operation and cumulative dosage of sufentanil at 24 h postoperatively in combined group were (410±129) μg and (14±4) μg, which were lower than those in control group [(580±225) μg and (21±11) μg] (both P<0.05). Cumulative dosage of sufentanil at 48 h postoperatively in combined group was (29±11) μg, while in control group was (36±14) μg, and the difference between the two groups was not statistically significant (P=0.131). The incidence of postoperative dizziness in combined group was 6.7% (1/15), which was lower than that of control group [40.0% (6/15)] (P=0.031). The incidence of nausea and pruritus was 6.7% (1/15) and 0 in combined group, while 20.0% (3/15) and 6.7% (1/15) in control group, with no statistical significance (both P>0.05). Conclusion: Serratus plane block combined with pectoral nerve block Ⅰ can effectively relieve postoperative pain, decrease the need for opioids, and reduce the incidence of adverse effects.

[Comparison of the anesthetic effects of mivacurium and cisatracurium besylate in laser laryngeal microsurgery]

Objective: To compare the anesthetic effects of mivacurium and cisatracurium besylate in laser laryngeal microsurgery, and to provide clinical evidence and reference for further optimization of muscle relaxation application. Methods: From October 2021 to January 2022, fifty-six patients of Beijing Tongren Hospital, Capital Medical University, scheduled for laser laryngeal microsurgery with general anesthesia, were enrolled. These patients, aged 18-65 years old, 25 males and 31 females, were divided into two groups (n=28) by random number table method. Cisatracurium besylate group (group C): cisatracurium besylate was injected at 0.1 mg/kg. Normal saline was continuously infused during operation. Mivacurium group (group M):Mivacurium was injected at 0.25 mg/kg and continuously infused at 0.3 mg·kg^-1·h^-1 during operation.The intubation time, the extubation time, recovery index, Cooper's score, Cormack-Lehane grade, surgical condition grade, postoperative residual neuromuscular block and allergic related adverse events were compared between the two groups. Results: The intubation time and the extubation time of group M were (3.7±1.1) and (16.2±5.0) min, which were statistically significant shorter than those of group C (4.9±0.7) and (26.4±8.6) min (all P<0.05). The recovery indexes of the patients in group M and group C were (4.5±3.4) and (6.2±5.0) min. The Cooper's scores of the two groups were both 9(9, 9). The Cormack-Lehane grades of the two groups were all grade Ⅰ. The number of cases with good/excellent surgical condition grades in group M and group C were 5/23 and 0/28. There were no significant differences in recovery index, Cooper's score, Cormack-Lehane grades and surgical condition grades between the two groups (all P>0.05). The TOF ratio of group M in the post anesthesia care unit (PACU) was (95.7±2.6) %, which was significantly higher than (92.9±3.9) % of group C(P=0.015). There were no significant differences in MAP and HR between the two groups at different time points (all P>0.05). The incidence of skin flushing in group M and group C was 10.7% (3/28) and 0, and the difference was not statistically significant (P=0.074). There were no cases of severe hypotension, significantly elevated airway pressure or airway spasm in both groups. Conclusion: In laser laryngeal microsurgery, compared with cisatracurium besylate, mivacurium has shorter intubation time and extubation time, stable hemodynamics, no significant increase in allergic related adverse events. mivacurium is safe and effective.

[Effects of topical anesthesia with 1% tetracaine on hemodynamic responses in microlaryngosurgery]

Objective: To observe the effects of topical anesthesia with 1% tetracaine on hemodynamic responses in general anesthesia patients undergoing microlaryngosurgery. Methods: From October 2021 to December 2021, 92 patients (46 males and 46 females) in Beijing Tongren Hospital, with a median age [M (Q₁, Q₃)] of 51 (42, 57) years who scheduled for microlaryngosurgery under general anesthesia, were divided into two groups (n=46 in each group) using the random number table method. Group T received topical anesthesia with 1% tetracaine at the root of the tongue and epiglottis and glottis on the basis of general intravenous anesthesia induction, with 0.5 ml at each position, while the control group (group C) received equal volume of normal saline. Heart rate (HR) and mean arterial pressure (MAP) were recorded at the time of patients entering the operating room (baseline), after induction, after intubation, immediately after suspending laryngoscopy, 1 min after suspending laryngoscopy, 3 min after suspending laryngoscopy, 5 min after suspending laryngoscopy and immediately after extubation. The recovery profiles, including time to recover breathing, time to open eyes, time to extubation and adverse reactions were evaluated during recovery period. Results: The MAP of patients in group T at baseline, after induction, after intubation, immediately after suspending laryngoscopy, 1 min after suspending laryngoscopy, 3 min after suspending laryngoscopy, 5 min after suspending laryngoscopy and immediately after extubation were (99.4±12.9), (78.5±8.8), (79.2±10.2), (100.6±17.0), (101.9±14.7), (100.8±13.9), (97.4±12.1), (107.3±16.8) mmHg (1 mmH=0.133 kPa), respectively, while in group C were (99.5±11.6), (80.9±12.8), (90.5±16.0), (109.5±20.4), (108.0±18.9), (103.7±15.5), (100.1±13.3), (114.2±17.3) mmHg, respectively. The two critical time points of MAP after intubation and immediately suspending laryngoscopy in group C were significantly higher than group T (P<0.05).The HR of patients in group T at baseline, after induction, after intubation, immediately after suspending laryngoscopy, 1 min after suspending laryngoscopy, 3 min after suspending laryngoscopy, 5 min after suspending laryngoscopy and immediately after extubation was (71.3±10.6), (66.0±10.1), (69.5±11.4), (61.3±14.2), (69.8±9.8), (71.0±10.6), (70.6±11.0), (78.8±11.6) bmp, respectively, while in group C were (73.1±10.9), (67.8±9.9), (79.5±12.9), (57.1±18.1), (69.2±12.8), (71.4±11.7), (70.7±11.5), (85.3±13.0) bmp, respectively. The two critical time points of HR after intubation and after extubation in group C were significantly higher than that of group T (P<0.05). The time to recover breathing in the two groups was (11.8±3.5) min and (11.3±4.6) min, respectively. The time to open eyes was (12.0±3.3) min and (11.5±5.0) min, respectively. The time to extubation was (13.2±3.7) min and (12.6±4.9) min, respectively. There were no statistically significant difference in time to recovery between the two groups (P>0.05). Likewise, there were no toxic reactions to local anesthetics, respiratory depression, hypoxemia, laryngospasm and cough occurred in either group. Conclusion: Topical anesthesia with 1% tetracaine can effectively reduce the hemodynamic changes without influencing patient's recovery, and does not increase the incidence of adverse reactions.

AB0784 Symptoms compatible with Rome IV functional bowel disorder in patients with ankylosing spondylitis

Background

Clinical manifestations of gut problems except for inflammatory bowel disease (IBD) have not been well-established in patients with ankylosing spondylitis (AS). One study investigated that 30% patients with axial spondyloarthritis (axSpA) had irritable bowel syndrome (IBS) symptoms meeting Rome III criteria.[1]

Objectives

To determine the frequency of symptoms meeting Rome IV functional bowel disorder (FBD) in patients with AS, investigate factors associated with FBD symptoms, and assess whether having FBD symptoms might influence AS disease activity.

Methods

In this cross-sectional study, we consecutively enrolled 153 AS patients without known colonic ulcer and 56 sex- and age-matched controls to evaluate FBD (or its subtypes) symptoms.[2] In AS group, logistic regression models were used to explore whether demographic data, disease activity, level of gut inflammation, drug use, and fibromyalgia [3] were associated with presence of gut symptoms. Finally, potential impacts of gut symptoms on AS disease status were assessed in linear regression models.

Results

Sixty (39.2%) of 153 AS patients had FBD symptoms, which was more prevalent than controls (23.2%). Besides, symptoms compatible with IBS and chronic diarrhea were detected in 18 and 43 AS patients respectively. For AS group, multivariable logistic regression analyses showed that symptoms of FBD, IBS, and chronic diarrhea were negatively associated with using non-steroidal anti-inflammatory drug (NSAID), and positively associated with comorbid fibromyalgia, respectively. In exploration about effects of FBD (or its subtypes) symptoms on AS disease activity by multivariable linear regression analyses, FBD symptoms and chronic diarrhea had positive associations with assessments of AS respectively.

Conclusion

Patients with AS had frequent symptoms compatible with FBD, IBS, and chronic diarrhea, proportions of which were lower in those with NSAID-use. The improvement of FBD symptoms, especially chronic diarrhea, might be conducive to disease status of AS patients.

References

[1]Wallman JK, et al. Ann Rheum Dis. 2020;79:159-61.

[2]Mearin F, et al. Gastroenterology. 2016;18:S0016-5085(16)00222-5.

[3]Wolfe F, et al. J Rheumatol. 2011;38:1113-22.

Figure 1.

Frequencies with symptoms meeting FBD criteria

Table 1.

Univariable and multivariable associations between gut symptoms and assessments of AS

Gut symptomsUnivariableMultivariableβpβpASDAS-CRPaFBD symptoms0.2340.1120.294< 0.001IBS symptoms0.0390.863Chronic diarrhea0.2170.1720.3010.002BASDAIbFBD symptoms0.747< 0.0010.764< 0.001IBS symptoms0.2020.560Chronic diarrhea0.7610.0020.845< 0.001BAS-GcFBD symptoms0.936< 0.0010.979< 0.001IBS symptoms0.0590.889Chronic diarrhea0.9030.0030.9490.001ASAS HIdFBD symptoms1.941< 0.0011.6730.003IBS symptoms2.2630.0081.7690.046Chronic diarrhea1.5000.0151.3430.030BASFIeFBD symptoms0.4330.0490.4280.048IBS symptoms0.2960.376Chronic diarrhea0.4480.0600.4250.069BASMIfFBD symptoms-0.3730.190-0.4930.075IBS symptoms-0.4420.304Chronic diarrhea-0.1790.564　　

Besides gut symptoms, other clinical variables (Block-1) being chosen into hierarchical multivariable models were as follows: aHLA-B27, lnCRP, and lnESR; bHLA-B27 and lnESR; cHLA-B27 and lnCRP; dsex and TNFi; eHLA-B27, lnESR, and TNFi; fage and lnESR. Missing data ranging from 1-7%.

Disclosure of Interests

None declared

Dual-channel metasurfaces for independent and simultaneous display in near-field and far-field

The operation of near-field and far-field can be employed to display holographic and nanoprinting images, which significantly improves the information density. Previous studies have proposed some approaches to display the images independently or simultaneously, but cannot satisfy these two characteristics in a single structure under the same incident light. Here, a single layer multifunctional metasurface is proposed to display a nanoprinting image and a holographic image independently and simultaneously. By tailoring the dimensions of each nanobricks and adopting different orientation angle, the amplitude and phase can be artificially designed. Moreover, enabled by the simulated annealing algorithm, we take the impact of both amplitude and phase of each nanobrick into consideration, which eliminates the unnecessary influence of amplitude on holographic image. Compared with previous work, our metasurfaces markedly improve the quality of holographic image with simple structures while not affecting the nanoprinting image. To be exact, it breaks the coupling between the near-field and far-field, achieving independent and simultaneous control of both fields. Our proposed metasurfaces carry characteristics of simple manufacture, little crosstalk, and great compactness, which provides novel applications for image displays, optical storage and information technology.

Band-tunable achromatic metalens based on phase change material

Achromatic metalens have the potential to significantly reduce the size and complexity of broadband imaging systems. A large variety of achromatic metalens has been proposed and most of them have the fixed achromatic band that cannot be actively modified. However, band-tunable is an important function in practical applications such as fluorescence microscopic imaging and optical detection. Here, we propose a bilayer metalens that can switch achromatic bands by taking the advantage of the high refractive index contrast of Sb₂S₃ between amorphous and crystalline state. By switching the state of Sb₂S₃, the achromatic band can be reversibly switched between the red region of visible spectrum (650-830 nm) and the near-infrared spectrum (830-1100 nm). This band-tunable design indicates a novel (to our knowledge) method to solve the problem of achromatic focusing in an ultrabroad band. The metalens have an average focusing efficiency of over 35% and 55% in two bands while maintaining diffraction-limited performance. Moreover, through proper design, we can combine different functionalities in two bands such as combining achromatic focusing and diffractive focusing. The proposed metalens have numerous potential applications in tunable displaying, detecting devices and multifunctional devices.

[A pedigree study of Loeys-Dietz syndrome type 4 with skeletal deformity related to a novel TGFβ2 mutation]

Objective: Loeys-Dietz syndrome is a rare type of hereditary connective tissue disease. This study was aimed to analyze the clinical characteristics and gene mutations in a family of Loeys-Dietz syndrome with skeletal deformity. Methods: Clinical data of the proband and family members were collected and biochemical measurements and radiological examinations were conducted. Genomic DNA was extracted from peripheral blood of the family members. Whole-exome sequencing was performed to determine the mutation sites in the proband, and Sanger sequencing was applied to verify the candidate mutation in the other family members. Results: The proband is a 34-year-old man with deformities of lower extremities for more than 30 years. Physical examinations showed dolichostenomelia, pes planus, joint laxity and scoliosis. Echocardiography revealed the dilatation of aortic root at the level of the sinuses of Valsalva. A heterozygous missense mutation (c. 220A>C, p.Thr74Pro) in exon 1 of TGFβ2 gene was identified in the proband. The same mutation was detected in his sister and niece with similar clinical features such as deformities of lower extremities and pes planus. This novel mutation has not been reported in ExAC or 1000G and was predicted to be deleterious, supporting a diagnosis of Loeys-Dietz syndrome type 4. Conclusions: Loeys-Dietz syndrome type 4 is caused by TGFβ2 mutations. Skeletal deformity is one of the distinctive features. Genetic testing is helpful for the early diagnosis and differential diagnosis from other connective tissue diseases.

Electronically Controlled Time-Domain Integral Average Depolarizer Based on a Barium Titanate (BTO) Metasurface

A depolarizer, a kind of optical element that converts polarized light to unpolarized light, has been found massive applications in classical optics. However, depolarizers based on metasurface which can be applied in integrated optics have rarely been proposed. In this paper, an electronically controlled metasurface depolarizer is demonstrated based on the time-domain integral average method and nano-material barium titanate. It obtains emergent light with a degree of polarization reduced to 2.5% when hit by linearly polarized light at 633 nm, and has a transmission efficiency greater than 72%. This depolarizing metasurface can be designed on-demand, immunizing the degree of the emergent light from its size, and has the simple electronic control with high-speed response.

Definition of large niche after Cesarean section based on prediction of postmenstrual spotting: Chinese cohort study in non-pregnant women

OBJECTIVE

A large niche after Cesarean section (CS) is associated with long-term complications, of which postmenstrual spotting is associated positively with the size of the niche. However, the diagnosis of a large niche in the literature is inconsistent and the definition is largely subjective. The aim of this study was to generate a definition for a large niche in non-pregnant women based on the presence of postmenstrual spotting.

METHODS

Women who had undergone CS in our hospital between January 2012 and June 2017 were selected randomly from our database, contacted by telephone and subsequently examined between January 2016 and June 2020. Eligible for inclusion were non-pregnant women who had their last CS more than 1 year earlier and agreed to undergo transvaginal sonography (TVS). All participants underwent examination of their CS scar by TVS (two-dimensional color Doppler) during the midfollicular phase. Niche depth, length, width, residual myometrial thickness (RMT), adjacent myometrial thickness (AMT) and ratio of niche depth/AMT were recorded. Women diagnosed with a niche, defined as an indentation at the site of the CS with a depth of at least 2 mm, were classified into two groups (symptomatic or asymptomatic) according to whether they experienced postmenstrual spotting. Logistic regression analysis was used to establish the best cut-off values for the niche parameters to predict postmenstrual spotting. A new definition was generated based on the niche parameters with the highest area under the receiver-operating-characteristics (ROC) curve (AUC) for the prediction of postmenstrual spotting.

RESULTS

A total of 727 women who had a CS > 1 year earlier underwent TVS examination, of whom 263 were diagnosed with a niche (prevalence of 36.2%). Of these, 160 women experienced postmenstrual spotting and 103 were asymptomatic. The three variables with the highest AUC for prediction of postmenstrual spotting were niche depth/AMT ratio (AUC, 0.798; 95% CI, 0.745-0.852), niche depth (AUC, 0.731; 95% CI, 0.668-0.795) and RMT (AUC, 0.683; 95% CI, 0.618-0.748). Based on the best cut-offs according to ROC-curve analysis, a large niche was defined as: niche depth ≥ 0.50 cm, RMT ≤ 0.21 cm or niche depth/AMT ratio ≥ 0.56. The prevalence of a large niche according to this definition was 22.4% (163/727). The new definition had a specificity of 61.17% (95% CI, 52.34-70.41%) and sensitivity of 76.87% (95% CI, 70.28-84.16%) for a large niche.

CONCLUSION

This study has provided a new definition for a large niche after CS. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Crizotinib in patients with tumors harboring ALK or ROS1 rearrangements in the NCI-MATCH trial

The NCI-MATCH was designed to characterize the efficacy of targeted therapies in histology-agnostic driver mutation-positive malignancies. Sub-protocols F and G were developed to evaluate the role of crizotinib in rare tumors that harbored either ALK or ROS1 rearrangements. Patients with malignancies that progressed following at least one prior systemic therapy were accrued to the NCI-MATCH for molecular profiling, and those with actionable ALK or ROS1 rearrangements were offered participation in sub-protocols F or G, respectively. There were five patients who enrolled on Arm F (ALK) and four patients on Arm G (ROS1). Few grade 3 or 4 toxicities were noted, including liver test abnormalities, and acute kidney injury. For sub-protocol F (ALK), the response rate was 50% (90% CI 9.8-90.2%) with one complete response among the 4 eligible patients. The median PFS was 3.8 months, and median OS was 4.3 months. For sub-protocol G (ROS1) the response rate was 25% (90% CI 1.3-75.1%). The median PFS was 4.3 months, and median OS 6.2 months. Data from 3 commercial vendors showed that the prevalence of ALK and ROS1 rearrangements in histologies other than non-small cell lung cancer and lymphoma was rare (0.1% and 0.4% respectively). We observed responses to crizotinib which met the primary endpoint for ALK fusions, albeit in a small number of patients. Despite the limited accrual, some of the patients with these oncogenic fusions can respond to crizotinib which may have a therapeutic role in this setting.

Development of an indirect enzyme-linked immunosorbent assay for the detection of novel chicken orthoreovirus

A novel avian orthoreovirus (N-ARV) variant characterized with obvious arthritis and synovial inflammation, was isolated from Shandong, China in May 2016. It caused chicken poor growth and enormous economic losses to the poultry industry of China. However, there are few effective methods for detecting the antibody levels of N-ARV. In this study, a viral structural protein σC was expressed using the prokaryotic expression vector pET32a (+). The target protein was obtained by inducing for 6 hours at an IPTG concentration of 0.6mM. The optimal dilution of the coating antigen and serum antibody were determined to be 1000 fold and 10 fold respectively. A specificity test showed that there was no positive reactivity between N-ARV and other pathogens, and when the positive serum was diluted 100 times detection results were still checkable. The repeatability of this method was determined by the inter assay and intra assay tests with variability ranging from 4.85% to 7.93%. In conclusion, this indirect enzyme linked immunosorbent assay (ELISA) will be useful for large-scale serological surveys and monitoring antibody levels in N-ARV infection.

Theoretical Study on Generation of Multidimensional Focused and Vector Vortex Beams via All-Dielectric Spin-Multiplexed Metasurface

The optical vortex (OV) beams characterized by orbital angular momentum (OAM) possess ubiquitous applications in optical communication and nanoparticle manipulation. Particularly, the vortex vector beams are important in classical physics and quantum sciences. Here, based on an all-dielectric transmission metasurface platform, we demonstrate a spin-multiplexed metadevice combining propagation phase and Pancharatnam–Berry (PB) phase. By utilizing a phase-only modulation method, the metadevice can generate spin-dependent and multidimensional focused optical vortex (FOV) under the orthogonally circularly polarized incident light, and it can successfully realize the multiplexed of the above-mentioned FOVs for linearly polarized light. Meanwhile, the superposition of multiple OAM states can also produce vector vortex beams with different modes. Additionally, the evolution process of the electric field intensity profile is presented after the resultant vector vortex beams through a horizontal linear polarization. This work paves an innovative way for generating structured beams, and it provides promising opportunities for advanced applications in optical data storage, optical micromanipulation, and data communication.

Hydroxyethyl cellulose sensitized SMDMS structure with optical fiber relative humidity and temperature simultaneous measurement sensor

We have manufactured an intensity modulated optical fiber SMDMS sensor with hydroxyethyl cellulose (HEC) hydrogel coating for simultaneous measurement of RH and temperature. The SMDMS sensor was manufactured by splicing single-mode fiber (SMF), multi-mode fiber (MMF), dispersion compensation fiber (DCF), MMF, and SMF in sequence to form a structure of SMF + MMF + DCF + MMF + SMF (SMDMS). The cladding of MMFs and DCF were corroded by hydrofluoric acid (HF) and coated with HEC hydrogel to excite a strong evanescent field and increase the sensitivity of the SMDMS sensor. The adsorption of water molecules by HEC will cause a change in the effective refractive index of cladding mode, which will eventually change the intensity of the transmission spectrum. The experimental results indicate that the sensitivities are 0.507 dB/%RH and 0.345 dB/°C in the RH range of 30%-80% and temperature range of 10°C-50°C, respectively. At last, a dual-parameter measurement matrix is constructed based on the experimental results to achieve the simultaneous measurement of RH and temperature. The SMDMS sensor has the advantages of high sensitivity and good robustness, and has potential application prospects in daily life and other fields.

Switchable Multifunctional Meta-Surface Composed by Dielectric-Metal Hybrid Antenna Array Architecture

Strontium titanate (STO), the dielectric material, has caught the world’s attention due to its outstanding properties, such as high permittivity, high refractive index, and low loss in the terahertz band. Its permittivity is relevant to the environment temperature. Herein, a multifunctional meta-surface composed of a dielectric-metal hybrid antenna array has been demonstrated, which is a single-layer STO elliptic cylinder. On the one hand, when the environment temperature is 300 K, the proposed meta-surface can achieve perfect absorption and polarization conversion in the frequency range from 0.1 to 0.25 THz; particularly, the meta-surface absorptance can reach 99.97% and 99.92% at a frequency of 0.103 and 0.13 THz respectively, and while it is used as a polarization conversion device, the degree of circular polarization and the ellipticity angle can reach 0.986 and 44.5° at a frequency of 0.228 THz. On the other hand, when the environment temperature changes from 300 to 450 K, the absorption peak changes with the temperature, and the average absorptance reaches 96% at resonance frequency. The proposed meta-surface can be applied in many fields, such as optical sensing, imaging, and energy harvesting. Moreover, it provides a potential solution to research the integrated device in a complex electromagnetic environment.

Clinical characteristics, treatment strategies and oncologic outcomes of primary retroperitoneal tumours: a retrospective analysis in the Chinese population

INTRODUCTION

Primary retroperitoneal tumours (PRTs) are rare soft tissue tumours originating from the retroperitoneum. Although there has been considerable progress recently in diagnosis and treatment, the overall survival rate has not improved qualitatively. This study aimed to explore the clinical features, therapeutic strategies and prognosis of PRTs.

METHODS

Retrospective analysis of clinical data for 121 PRT patients admitted to Peking University Shenzhen Hospital from April 2003 to February 2017.

RESULTS

A total of 113 patients underwent surgery and 8 chose nonsurgical palliative treatment. There were 53 males and 68 females (ratio, 1:1.3; average age, 40.75 years), and the average tumour diameter was 9.69(2-40)cm. A total of 104 patients (92.04%) underwent complete resection, 5 (4.42%) underwent palliative resection and 21 (18.58%) underwent combined visceral resection. The pathological diagnosis was benign in 88 cases (72.73%) and malignant in 33 cases (27.27%). A total of 101 patients (83.47%) were followed for an average of 5.82 years. At the end of follow up, the recurrence and survival rates were 2.63% and 93.42% for benign tumours, respectively, and 24.00% and 60.00% for malignant tumours (p<0.01).

CONCLUSIONS

Imaging plays important roles in localising and characterising tumours, guiding treatment strategies. Complete tumour resection is key to reducing postoperative recurrence and improving survival. According to the postsurgical pathological results, combinations including radiotherapy, chemotherapy or targeted therapy are beneficial for improving prognosis.

[Comparison of the post-operative analgesic effect of ultrasound-guided serratus anterior plane block combined with pectoral nerves block Ⅰ and thoracic paravertebral block in radical mastectomy]

Objective: To investigate the serratus anterior plane block combined with pectoral nerves block I can produce a non-inferior analgesic effect compared with thoracic paravertebral block for radical mastectomy. Methods: From October 2020 to February 2021, Sixty-four patients of Beijing Tongren Hospital, Capital Medical University scheduled for radical mastectomy with general anesthesia,were divided into two groups (n = 32 each) using a random number table method: thoracic paravertebral block group (TPVB group) and serratus anterior plane block combined with pectoral nerves block I group (S&P group). All patients received patient controlled intravenous analgesia (PCIA) postoperatively. The numerical rating scale (NRS) at post anesthesia care unit (PACU), 4, 8, 12, 24, 48 h after operation were compared between the two groups. Sufentanil cumulative dosage of PCIA in 24 h and 48 h, first press time after operation, total press times, the dosage of propofol, remifentanil and vasoactive drugs during operation, intraoperative blood pressure and heart rate, the operation time of block and adverse effects were all compared. Non-inferiority could be claimed if the difference of sufentanil cumulative dosage in 24 h between S&P group and TPVB group is higher than the negative value (-3.8) of the non-inferiority effect. Results: There was no significant difference in postoperative NRS at PACU, 4, 8, 12, 24, 48 h after operation, first press time after operation, total press times, propofol and remifentanil dosage, sufentanil cumulative dosage of PCIA in 24 h and 48 h, and adverse effects (all P>0.05). The sufentanil cumulative dosage of PCIA in 24 h of S&P group and of TPVB group were (15.8±4.7) μg and (15.2±3.2) μg. The 95% confidence interval (CI) of the difference between S&P group and of TPVB group was -1.478 to 2.694, and the lower limit was greater than non-inferiority margin -3.8. The mean arterial pressure of TPVB patients after induction and at the beginning of the operation were (63±7) mmHg and (70±7) mmHg, which were significantly lower than the (77±5) mmHg and (79±8) mmHg at the same time in the combination group (both P<0.05). The frequency of vasoactive drugs usage in TPVB group was 56.3%, which was statistically significant higher than the 18.8% in S&P group (P<0.01). Nerve block time in TPVB group was 10 (9, 11) min, which was significantly longer than 8 (6, 10) min in S&P group (P<0.01). Conclusion: The serratus anterior block combined with pectoral nerves block I can produce a non-inferior analgesic effect compared with thoracic paravertebral block for radical mastectomy, and the intraoperative hemodynamics is more stable and the block time is shorter than that of thoracic paravertebral block for radical mastectomy.

Single core-offset Mach-Zehnder interferometer coated with PVA for simultaneous measurement of relative humidity and temperature

A single core-offset Mach-Zehnder interferometer (MZI) coated with polyvinyl alcohol (PVA) for simultaneous measurement of relative humidity (RH) and temperature is proposed in this paper. The sensing structure is fabricated by splicing dispersion compensating fiber (DCF) and no-core fiber (NCF) and splicing two single-mode fibers (SMF) at both ends, where the core-offset is located at the splicing of SMF and DCF. A part of the cladding of DCF is etched to excite the high-order cladding mode (LP₁₀), and PVA is coated on the etched area. The refractive index of PVA varies due to the adsorption of water molecules. Therefore, when the ambient relative humidity and temperature change, the change of MZI phase difference causes the wavelength of the resonant dip to shift. The experimental results indicate that the proposed sensor has a sensitivity of 0.256 nm/RH% for RH range of 30%-95%, and a sensitivity of 0.153 nm/℃ for temperature range of 20℃-80℃, respectively. The simultaneous measurement of RH and temperature can be achieved by demodulating the sensitivity coefficient matrix. The proposed sensor has the characteristics of good repeatability, high sensitivity, and good stability, which make it potentially applications for the detection of RH and temperature measurement.

Welding fume nanoparticles from solid and flux-cored wires: Solubility, toxicity, and role of fluorides

Welding fume particles are hazardous. Their toxicity likely depends on their composition and reactivity. This study aimed at exploring the role of sodium or other fluorides (NaF), which are intentionally added to flux-cored wire electrodes for stainless steel welding, on the solubility (in phosphate buffered saline) and toxicity of the generated welding fume particles. A multi-analytical particle characterization approach along with in-vitro cell assays was undertaken. The release of Cr(VI) and Mn from the particles was tested as a function of fluoride solution concentration. The welding fume particles containing NaF released significantly higher amounts of Cr(VI) compared with solid wire reference fumes, which was associated with increased cytotoxicity and genotoxicity in-vitro. No crystalline Na or potassium (K) containing chromates were observed. Cr(VI) was incorporated in an amorphous mixed oxide. Solution-added fluorides did not increase the solubility of Cr(VI), but contributed to a reduced Mn release from both solid and flux-cored wire fume particles and the reduction of Cr(VI) release from solid wire fume particles. Chemical speciation modeling suggested that metal fluoride complexes were not formed. The presence of NaF in the welding electrodes did not have any direct, but possibly an indirect, role in the Cr(VI) solubility of welding fumes.