Dynamically crosslinked chiral optics sensing for ultra-sensitive VOCs detection.

Chiroptical sensing with real-time colorimetrical detection has been emerged as quantifiable properties, enantioselective responsiveness, and optical manipulation in environmental monitoring, food safety and other trace identification fields. However, the sensitivity of chiroptical sensing materials remains an immense challenge. Here, we report a dynamically crosslinking strategy to facilitate highly sensitive chiroptical sensing material. Chiral nematic cellulose nanocrystals (CNC) were co-assembled with amino acid by a two-step esterification, of which a precisely tunable helical pitch, a unique spiral conformation with hierarchical and numerous active sites in sensing performance could be trigged by dynamic covalent bond on amines. Such a CNC/amino acid chiral optics features an ultra-trace amount of 0.08 mg/m3 and a high sensitivity of 60 nm/(mg/m3) for formaldehyde gas at a molecule level detection, which is due to the three synergistic adsorption enhancement of dynamic covalent bonded interaction, hydrogen bonded interaction and van der Waals interaction. Meanwhile, an enhancement hierarchical adsorption of CNC/amino acid chiral materials can be readily representative to the precise helical pitch and colorimetrical switch for sensitive visualization reorganization.

Association of the 6-minute walking test ratio and difference with pulmonary function in patients with interstitial lung disease.

OBJECTIVES: To examine the associations between 6-minute walk test (6MWT) and lung functions, blood gas analysis findings, fractional exhaled nitric oxide (FeNO), and hospital stay in interstitial lung disease (ILD). METHODS: The present retrospective study included patients hospitalized in Beijing Hospital of Traditional Chinese Medicine, Capital Medical University between September 2018 and December 2019. The outcomes included the difference between the actual and predicted 6MWT values (6MWT difference) and the ratio of the actual to predicted 6MWT value (6MWT ratio). RESULTS: This study included 137 patients. The predicted 6MWT value was 519±61 m and the actual 6MWT value was 449 (196.5,694)m. The 6MWT ratio was 84.7±177.6 and 6MWT difference was 73.9±95.1 m. Fractional exhaled nitric oxide (FeNO) (ß= -2.157, standard error [SE]=0.836, p=0.014) and diffusing capacity of the lungs for carbon monoxide (DLCO) (ß= -22.528, SE=7.48, p=0.004) had independent associations with 6MWT difference. The FeNO (ß=0.403, SE=0.163, p=0.018) and DLCO (ß=4.355, SE=1.458, p=0.005) had independent associations with 6MWT ratio. CONCLUSION: In ILD, 6MWT difference and 6MWT ratio were associated with FeNO and DLCO. The 6MWT value was not associated with hospital stay. Therefore, the 6MWT might be a surrogate marker of pulmonary function in clinical ILD.

Influence of Pump Current Waveform on The Mitigation of Transverse Mode Instability in Fiber Laser Oscillator.

We carry out a detailed investigation of TMI mitigation by pump modulation based on multiple current waveforms in a fiber laser oscillator. Compared with continuous wave (CW), the modulation of various waveforms, including sinusoidal wave, triangular wave, and pulse wave with a duty cycle of 50% and 60%, can increase the TMI threshold. The average output power of a stabilized beam is boosted via the adjustment of phase difference between the signal channels. The TMI threshold is increased to 270 W under a modulation of pulse wave (duty cycle: 60%) with a phase difference of 440 µs, where the beam quality is 1.45. This threshold can be further improved by adding groups of pump LDs and drivers, which is a promising approach for beam stabilization of high-power fiber lasers.

The effect of Er3+ concentration on the kinetics of multiband upconversion in NaYF4:Yb/Er microcrystals.

In Yb-Er co-doped upconversion (UC) nanomaterials, upconversion luminescence (UCL) can be modulated to generate multiband UCL emissions by changing the concentration of activator Er3+. Nonetheless, the effect of the Er3+ concentrations on the kinetics of these emissions is still unknown. We here study the single ß-NaYF4:Yb3+/Er3+ microcrystal (MC) doped with different Er3+ concentrations by nanosecond time-resolved spectroscopy. Interestingly, different Er3+ doping concentrations exhibit different UCL emission bands and UCL response rates. At low Er3+ doping concentrations (1 mol%), multiband emission in ß-NaYF4:Yb3+/Er3+ (20/1 mol%) MCs could not be observed and the response rate of UCL was slow (5-10 µs) in ß-NaYF4:Yb3+/Er3+. Increasing the Er3+ doping concentration to 10 mol% can shorten the distance between Yb3+ ions and Er3+ ions, which promotes the energy transfer between them. ß-NaYF4:Yb3+/Er3+ (20/10 mol%) can achieve obvious multiband UCL and a quick response rate (0.3 µs). However, a further increase in the Er doping concentration (80 mol%) makes MCs limited by the CR process and cannot achieve the four-photon UC process (4F5/2 → 2K13/2 and 2H9/2 → 2D5/2). Therefore, the result shows that changing the Er3+ doping concentration could control the energy flow between the different energy levels in Er3+, which could affect the response time and UCL emission of the Yb/Er doped rare earth materials. Our work can facilitate the development of fast-response optoelectronics, optical-sensing, and display industries.

Influence of surface roughness on nanosecond laser-induced shock wave enhancement effects.

In this paper, an effective method is proposed for improving the energy of the shock waves that are generated by plasma expanding outward and colliding with another gas. Silicon targets are used as the response medium with roughness of 2.3 nm, 457.8 nm, 1.1 µm, and 37.1 µm, respectively. A 532-nm-laser with a pulse duration of 8 ns and a repetition rate of 10 Hz is used as the irradiation source. An intensified charge-coupled device (ICCD) is used to photograph the morphology of the shock waves. The time-resolved emission images of silicon plasma plumes are observed between 20-200 ns. As the surface roughness of the target increases, the intensity of the shock wave gradually increases, and the energy of the shock wave reaches up to 39.45 mJ at a roughness of 37.1 µm.

Effect of dexmedetomidine on opioid consumption and pain control after laparoscopic cholecystectomy: a meta-analysis of randomized controlled trials.

INTRODUCTION: The clinical evidence on dexmedetomidine (DEX) for postoperative pain scores and opioid consumption remains unclear in laparoscopic cholecystectomy (LC). AIM: To evaluate whether DEX could reduce opioid consumption and pain control after LC. MATERIAL AND METHODS: A meta-analysis search of EMBASE, PubMed and Cochrane CENTRAL databases was performed and randomized controlled trials (RCTs) comparing DEX with control for adult patients undergoing LC were searched. The primary outcome was opioid consumption in the first 24 h after the operation. The secondary outcomes were the time of first request of analgesia, visual analogue scale (VAS) scores 24 h after the operation, the incidence of patients' need for rescue analgesics, opioid-related adverse effects, DEX-related adverse effects and other complications. RESULTS: There were fourteen aspects of twelve trials and 967 patients included in the analysis. DEX use significantly reduced the opioid consumption in the first 24 h after the operation (weighted mean difference (WMD), -19.17; 95% confidence interval (CI), -30.29 to -8.04; p = 0.0007), lengthened the time of first request of analgesia (WMD = 38.90; 95% CI: 0.88-76.93; p = 0.04) and lowered post-operative nausea or vomiting (PONV) (odds ratio (OR) = 0.49; 95% CI: 0.27-0.89; p = 0.02). CONCLUSIONS: Intravenous DEX infusion significantly improved the duration of the analgesic effect and reduced postoperative opioid consumption. Moreover, lower incidence of post-operative nausea or vomiting was found in the DEX group.

Aspirin Positively Contributes to Drosophila Intestinal Homeostasis and Delays Aging through Targeting Imd.

The intestine, a high-turnover tissue, plays a critical role in regulating aging and health in both vertebrates and invertebrates. Maintaining the epithelial barrier function of the intestine by preserving innate immune homeostasis significantly delays aging and prevents mortality. In an effort to explore effective chemicals and materials that can improve intestinal integrity, we performed a nonbiased screen utilizing Drosophila as an animal model. We showed that long-term uptake of aspirin markedly prevented age-onset gut leakage, the over-proliferation of intestinal stem cells, and the dysbiosis of commensal microbiota in fruit flies. Mechanistically, aspirin efficiently downregulated chronic activation of intestinal immune deficiency signaling during aging. Furthermore, our in vivo and in vitro biochemical analyses indicated that aspirin is a negative modulator in control of the K63-linked ubiquitination of Imd. Our findings uncover a novel regulatory mechanism by which aspirin positively modulates intestinal homeostasis, thus delaying aging, in Drosophila.

Chiral Nematic Coatings Based on Cellulose Nanocrystals as a Multiplexing Platform for Humidity Sensing and Dual Anticounterfeiting.

The need for a precise regulation of the properties of chiral nematic structures in response to external stimuli is addressed. Self-assembled iridescent coatings are produced under the effect of electrostatic interactions between cellulose nanocrystals and poly(acrylic acid), endowing a high anisotropic dissymmetry (>0.3) and sensitivity to environmental humidity (13.1 nm/1% at 68-75% relative humidity, RH). The phenomena associated with shifts in selective light reflection (green to orange) and polarization, facilitate tunable transmitted colors (blue to orange) at given rotation angles (RA). Such properties are conveniently integrated into a "RH-RA-color" ternary code that is introduced as an anticounterfeiting technology, taking advantage of multicolor patterns that conveniently track with changes in RH and RA. The proposed charge-driven assembly opens new opportunities for chiral nematic materials that enable precise optical sensing and information encryption.

A high-density crowd state judgment model based on entropy theory.

A high-density crowd state is prone to cause large-scale crowd stampede accidents that seriously threaten the people's security and property. The key to preventing crowd congestion is to accurately predict the location and time of crowd events, particularly when there is a high density of people. In this paper, the entropy theory is used to characterize the state of a crowded system. The theoretical entropy Sr and the actual entropy S of the crowd system are obtained according to the area occupied by the different crowd state The maximum entropy value and the actual entropy value under different conditions of the system are compared to judge the state of crowded extent. The results show that the model is practical and effective. According to the situation of the crowd, different management and evacuation measures are considered to prevent the occurrence of crowd accidents.

Dual Response of Photonic Films with Chiral Nematic Cellulose Nanocrystals: Humidity and Formaldehyde.

Manipulating functional stimuli-responsive materials has been a hot topic in the research of smart sensors and anticounterfeiting encryption. Here, a novel functional chiral nematic cellulose nanocrystal (CNC) film showing dual responsiveness to humidity and formaldehyde gas was fabricated. The chiral nematic CNC iridescent film could respond to environmental humidity and formaldehyde gas changes by reversible motion. Interestingly, the humidity sensitivity of the CNC iridescent film could be gated by exposing the film to formaldehyde gas. At the same time, the formaldehyde-responsive behavior is strongly affected by the relative humidity (RH), and the response range could be tuned by changing the RH over a wide range. Importantly, the formaldehyde-induced color change could be altered from invisible to visible by the naked eye when the film was exposed to a humid environment. The mechanism of this dual response of the CNC iridescent film is ascribed to the synergistic effect of cooperation and competition between water and formaldehyde molecules by constructing physical cross-linking networks by hydrogen bonds among water, formaldehyde, and CNCs. Furthermore, the "RH-concentration of formaldehyde gas-color" ternary colorimetric system was simulated, which is thought to endow the CNC iridescent film with great potential to act as a sensor in the convenient visible detection of gaseous formaldehyde. Furthermore, this work provided a promising strategy to design multi-gas-sensitive devices with convenient detection, good stability, and excellent reversibility.

Review of MEMS Based Fourier Transform Spectrometers.

Fourier transform spectrometers (FTS), mostly working in infrared (IR) or near infrared (NIR) range, provide a variety of chemical or material analysis with high sensitivity and accuracy and are widely used in public safety, environmental monitoring and national border security, such as explosive detection. However, because of being bulky and expensive, they are usually used in test centers and research laboratories. Miniaturized FTS have been developed rapidly in recent years, due to the increasing demands. Using micro-electromechanical system (MEMS) micromirrors to replace the movable mirror in a conventional FTS system becomes a new realm. This paper first introduces the principles and common applications of conventional FTS, and then reviews various MEMS based FTS devices.

[Analysis of related factors of carbapenem resistant Klebsiella pneumoniae infection in patients with artificial airway].

OBJECTIVE: To analyze the clinical characteristics and related influencing factors of carbapenem resistant Klebsiella pneumoniae (CRKP) in patients with artificial airway and mechanical ventilation in intensive care unit (ICU), and provide theoretical basis for clinical prevention of Klebsiella pneumoniae infection. METHODS: The clinical data of patients with pulmonary infection of Klebsiella pneumoniae in ICU of Beijing Shijitan Hospital Affiliated to Capital Medical University from January 2016 to December 2019 were collected. Compared CRKP pneumonia patients (study group) with carbapenem antibiotic sensitive Klebsiella pneumoniae (CSKP) pneumonia patients (control group), the clinical characteristics [gender, age, acute physiology and chronic health evaluation II (APACHE II), duration of mechanical ventilation, proportion of patients with mechanical ventilation > 10 days, use of antibiotics before detection of Klebsiella pneumoniae, white blood cell count (WBC), C-reactive protein (CRP), procalcitonin (PCT), albumin, bedridden for more than 1 month before admission, 28-day mortality] were analyzed. The drug resistance rates of Klebsiella pneumoniae in both groups and difference of drug resistance rate of Klebsiella pneumoniae to different antibiotics from 2016 to 2019 were compared. The risk factors of CRKP infection were analyzed by multivariate Logistic regression, and the related drug resistance genes were detected. RESULTS: Compared with the control group, the study group was older [years old: 81.5 (72.0, 86.0) vs. 78.0 (71.0, 80.5)], APACHE II [point: 25.00 (20.00, 34.00) vs. 19.00 (14.00, 23.25)] and proportion of patients with mechanical ventilation > 10 days [63.2% (182/288) vs. 12.8% (10/78)], the use of ß-lactamase inhibitor antibiotics before detection of Klebsiella pneumoniae [75.69% (218/288) vs. 30.77% (24/78)], the use of carbapenems [79.86% (230/288) vs. 41.03% (32/78)], the use of more than two kinds of antibiotics [80.90% (233/288) vs. 29.49% (23/78)], proportion of patients staying in bed for more than 1 month before admission [40.97% (118/288) vs. 11.54% (9/78)] and WBC [×109/L: 9.72 (6.41, 14.69) vs. 7.57 (5.84, 12.61)], CRP [mg/L: 74.45 (36.30, 158.88) vs. 39.22 (13.68, 92.51)], PCT [µg/L: 3.87 (0.82, 19.24) vs. 0.51 (0.25, 5.71)], 28-day mortality [21.5% (62/288) vs. 10.3% (8/78)] were higher, albumin [g/L: 24.1 (18.3, 28.6) vs. 30.1 (23.8, 35.1)] was lower, duration of mechanical ventilation [days: 16.5 (9.0, 19.0) vs. 7.0 (5.0, 10.0)] was longer, the proportion of patients with chronic obstructive pulmonary disease [COPD: 35.76% (103/288) vs. 11.54% (9/78)], malignant tumor [18.06% (52/288) vs. 5.13% (4/78)], renal failure [31.94% (92/288) vs. 11.54% (9/78)], shock [51.74% (149/288) vs. 19.23% (15/78)] were higher, and the differences were statistically significant (all P < 0.05). The drug resistance rates of Klebsiella pneumoniae to aztreonam, piperacillin/tazobactam, imipenem and ciprofloxacin were statistically significant (all P < 0.05); the drug resistance rates of Klebsiella pneumoniae to aztreonam and piperacillin/tazobactam were the highest in 2019 (88.17% and 86.02%, respectively), and the lowest in 2016 (70.65% and 57.61%, respectively). The drug resistance rate to imipenem was the highest in 2018 (86.32%), the lowest in 2016 (59.78%); the resistance rate to ciprofloxacin was the highest in 2016 (76.09%), and the lowest in 2018 (53.68%). The resistance rates of ceftetan, amikacin, piperacillin/tazobactam, ceftazidime, ceftriaxone and gentamicin in the study group were significantly higher than those in the control group (82.99% vs. 62.82%, 49.31% vs. 17.95%, 75.69% vs. 60.26%, 81.25% vs. 64.10%, 80.21% vs. 58.97%, 91.32% vs. 60.26%, all P < 0.05). Logistic regression analysis showed that COPD, severe hypoproteinemia, mechanical ventilation time > 10 days and the use of carbapenem antibiotics before detection of Klebsiella pneumoniae were independent risk factors of CRKP infection. Gene detection showed that there were TEM, KPC, AmpC, AAC(3)-II, ant(3")-I, qnrS and other drug resistance genes in CRKP. The detection rate of TEM was the highest (74.00%), and qnrA was the lowest (6.67%). CONCLUSIONS: The occurrence of CRKP in ICU patients with artificial airway and mechanical ventilation is related to many factors. It is necessary to shorten the mechanical ventilation time, avoid the nonstandard use of carbapenem antibiotics, and improve the serum albumin level, so as to reduce the incidence of CRKP pneumonia and improve the prognosis of patients.

A mitochondrion-targeted dual-site fluorescent probe for the discriminative detection of SO3 2- and HSO3 - in living HepG-2 cells.

Sulfur dioxide, known as an environmental pollutant, produced during industrial productions is also a common food additive that is permitted worldwide. In living organisms, sulfur dioxide forms hydrates of sulfite (SO2·H2O), bisulfite (HSO3 -) and sulfite (SO3 2-) under physiological pH conditions; these three exist in a dynamic balance and play a role in maintaining redox balance, further participating in a wide range of physiological and pathological processes. On the basis of the differences in nucleophilicity between SO3 2- and HSO3 -, for the first time, we built a mitochondrion-targeted dual-site fluorescent probe (Mito-CDTH-CHO) based on benzopyran for the highly specific detection of SO3 2- and HSO3 - with two diverse emission channels. Mito-CDTH-CHO can discriminatively respond to the levels of HSO3 - and SO3 2-. Besides, its advantages of low cytotoxicity, superior biocompatibility and excellent mitochondrial enrichment ability contribute to the detection and observation of the distribution of sulfur dioxide derivatives in living organisms as well as allowing further studies on the physiological functions of sulfur dioxide.

α-Fe2O3 hollow meso-microspheres grown on graphene sheets function as a promising counter electrode in dye-sensitized solar cells.

Although nanoparticles, nanorods, and nanosheets of α-Fe2O3 on graphene sheets have been synthesized, it remains a challenge to grow 3D α-Fe2O3 nanomaterials with more sophisticated compositions and structures on the graphene sheets. Herein, we demonstrate a facile solvothermal route under controlled conditions to successfully fabricate 3D α-Fe2O3 hollow meso-microspheres on the graphene sheets (α-Fe2O3/RGO HMM). Attributed to the combination of the catalytic features of α-Fe2O3 hollow meso-microspheres and the high conductivity of graphene, α-Fe2O3/RGO HMM exhibited promising electrocatalytic performance as a counter electrode in dye-sensitized solar cells (DSSCs). The DSSCs fabricated with α-Fe2O3 HMM displayed high power conversion efficiency of 7.28%, which is comparable with that of Pt (7.71%).

Elimination of self-mode-locking pulses in high-power continuous-wave Yb-doped fiber lasers with external feedback.

Sustained self-pulsing and self-mode-locking (SML) are detrimental to the performance of continuous-wave (CW) fiber lasers. We demonstrate an all-fiber method to eliminate SML pulsing by employing a low-reflectivity fiber Bragg grating (FBG) outside of a laser cavity to provide feedback. A narrow-bandwidth FBG is used to form an external cavity with the output coupler FBG, which suppresses the SML up to a certain output power level, at which point, the laser emission linewidth is still within the bandwidth of the FBG. On the other hand, a broad-bandwidth FBG forms a chirped cavity with the output coupler FBG, which can suppress the SML at a much higher power level, tested up to 50 W. This method provides a simple effective all-fiber solution for suppressing self-pulsing in CW fiber lasers at high pump levels with no need to change the laser configuration.

Physicochemical transformation of rice straw after pretreatment with a deep eutectic solvent of choline chloride/urea.

This study focused on the pretreatment with deep eutectic solvent of choline chloride (ChCl)/urea mixtures on rice straw and its chemical fractions of holocellulose, α-cellulose, and acid-insoluble-lignin (AIL). The pretreatment of ChCl/urea was significantly affected by the treated temperature prior to the treated time, and 130°C and 4h was an optimum condition for ChCl/urea pretreatment. The separation capacity of ChCl/urea on the chemical fractions was in an order of AIL (22.87%)> hemicellulose and amorphous cellulose (16.71%)>α-cellulose (9.60%). ChCl/urea had a higher selective solubility on lignin. The solubility of the whole fractionation of rice straw affected by ChCl/urea was a combination of solubilization on cellulose, hemicellulose and lignin. ChCl/urea pretreatment increased crystallinity index (CrI) of rice straw residue and α-cellulose, while had no obvious influence on CrI of holocellulose. The effect of structural properties of rice straw residue on enzymatic hydrolysis was also explored.

Spectral shaping for suppressing stimulated-Raman-scattering in a fiber laser.

We report on the effects of spectral shaping of the output coupler fiber Bragg grating (OC-FBG) in a Yb-doped fiber laser on the laser emission spectrum for the purpose of inhabiting stimulated Raman scattering (SRS). The lasers with four different OC-FBGs were built and characterized. We found that the laser with a multiple reflection peak chirped-moiré OC-FBG produced a broad laser emission linewidth, which, in turn, led to about 100 times lower the SRS emission as compared with the laser with a 0.19 nm Gaussian-shaped OC-FBG. A nearly flat-top laser output spectrum was obtained from the lasers with a triangle-shaped and chirped-moiré OC-FBG, respectively.

All-fiber, narrow linewidth and linearly polarized fiber laser in a single-mode-multimode-single-mode cavity.

We report the design of an all-fiber, linearly polarized Yb-doped fiber laser at 1064 nm with a narrow linewidth and high output power required by the master oscillator of the amplifier for high-power spectral beam combining. The laser has achieved linearly polarized output with a polarization extinction ratio of 23 dB, a narrow linewidth of ≤52 pm, and an output power of 32.7 W. Such performance was obtained by the cavity design that incorporated a wavelength-shifted PM fiber Bragg grating pair and single-mode-multimode-single-mode structure.

Analysis on correlation between SP and NK-1R and intranasal mucosal contact point headache.

CONCLUSION: Distribution of SP and NK-1R, especially NK-1R, in nasal mucosal tissue at contact point was higher compared with non-contact point. It was suggested that SP and NK-1R were associated with mucosal contact point headache. OBJECTIVES: To observe difference of substance P (SP) and NK-1 receptor (NK-1R) expression in tissues at contact point and non-contact point among the patients with intranasal mucosal contact point headache and speculate the role of SP and NK-1R in mucosal contact point headache. METHODS: SP and NK-1R in tissues of contact point and non-contact point among 40 patients with intranasal mucosal contact point headache were stained histologically by immunohistochemistry, and the mRNA level was detected by RT-PCR. RESULTS: SP was located in cytoplasm of acini epithelial cells, distributed in nasal mucosa tissues at both contact point and non-contact point. However, stain intensity was significantly increased at contact point (Z = -2.554, p < 0.05). NK-1R was located in the cytoplasm of acinar epithelial cells, inflammatory cells, and nerve fibers of contact point; only in cytoplasm of acinar epithelial cells and nerve fibers of non-contact point. Tinctorial rate of NK-1R increased significantly at contact point (χ(2) = 40.438, p < 0.01). mRNA level of SP and NK-1R was up-regulated in nasal mucosa at contact point compared with non-contact point.

Melkersson-Rosenthal syndrome: a retrospective study of 44 patients.

CONCLUSION: When patients with recurrent facial paralysis are encountered, otolaryngologists should check for fissured tongue, and question those patients about orofacial edema, minor symptoms, and family history. Histologic evidence is not necessary for the diagnosis of Melkersson-Rosenthal syndrome (MRS), while coronary high-resolution CT (HRCT) reconstruction of temporal bone and food allergen detection may be beneficial. Prophylactic decompression of the facial nerve for patients with appropriate electrophysiological indication may prevent further facial palsy attacks. OBJECTIVES: The objective of this study was to analyze the clinical features of a group of patients with MRS with major complaints of facial palsy treated at the Department of Otorhinolaryngology, and to comment on MRS from the perspective of otolaryngologists. METHODS: A retrospective review of patient database for the last 6 years in the Department of Otorhinolaryngology in Beijing Shijitan Hospital was performed to find patients diagnosed with MRS. RESULTS: A total of 44 MRS patients were included in this study. The mean age at onset was 14.1 years. A total of 13 (29.5%) patients had family history, 17 (38.6%) revealed broadened fallopian canal on coronary HRCT reconstruction of temporal bone, and 20/23 (87.0%) patients showed positive results in food allergen detection. Thirty-one patients accepted subtotal facial nerve decompression and only one patient had facial palsy recurrence on the same side as the operation.