Degradation of acid red 73 wastewater by hydrodynamic cavitation combined with ozone and its mechanism.

Many azo dyes are consumed in the textile and dyeing industry, which makes the wastewater recalcitrant and toxic to the aquatic environment. Dye degradation by the combination of hydrodynamic cavitation and ozone (HC + O3) has caused extensive interest. The degradation mechanism of the hybrid system needs further investigation. This study investigated the degradation of acid red 73 (AR73) by HC + O3. Meanwhile, the degradation pathways and mechanisms were present. The optimal operation parameters were: inlet pressure of 0.15 MPa, O3 dosage of 45 mg/min, initial dye concentration of 10 mg/L, and initial pH at 7.5. As a result, the decolorization rate, removal of UV254 and NH3-N were 100%, 71.28%, and 87.36% in 30 min, respectively. Humic acid and most of the co-existing anions (HCO3-, SO42-, Cl-, PO43-, NO3-) played a positive role in the degradation of AR73, while NO2- restrained. The reactive species of singlet oxygen (1O2), hydroxyl radicals (·OH) and super oxygen radicals (·O2-) showed synergism in the hybrid system, and the decolorization was attributed to the fracture of azo bonds by 1O2. Meanwhile, aromatic amines were generated and further degraded into small molecule compounds. The research certificated that the HC + O3 can be an effective technology for azo dye degradation.

The role of diffusion tensor imaging and tractography in the surgical management of brainstem gliomas.

OBJECTIVE: Diffusion tensor imaging (DTI) and diffusion tensor tractography (DTT) have the ability to noninvasively visualize changes in white matter tracts, as well as their relationships with lesions and other structures. DTI/DTT has been increasingly used to improve the safety and results of surgical treatment for lesions in eloquent areas, such as brainstem cavernous malformations. This study aimed to investigate the application value of DTI/DTT in brainstem glioma surgery and to validate the spatial accuracy of reconstructed corticospinal tracts (CSTs). METHODS: A retrospective analysis was performed on 54 patients with brainstem gliomas who had undergone surgery from January 2016 to December 2018 at Beijing Tiantan Hospital. All patients underwent preoperative DTI and tumor resection with the assistance of DTT-merged neuronavigation and electrophysiological monitoring. Preoperative conventional MRI and DTI data were collected, and the muscle strength and modified Rankin Scale (mRS) score before and after surgery were measured. The surgical plan was created with the assistance of DTI/DTT findings. The accuracy of DTI/DTT was validated by performing direct subcortical stimulation (DsCS) intraoperatively. Multiple linear regression was used to investigate the relationship between quantitative parameters of DTI/DTT (such as the CST score and tumor-to-CST distance [TCD]) and postoperative muscle strength and mRS scores. RESULTS: Among the 54 patients, 6 had normal bilateral CSTs, 12 patients had unilateral CST impairments, and 36 had bilateral CSTs involved. The most common changes in the CSTs were deformation (n = 29), followed by deviation (n = 28) and interruption (n = 27). The surgical approach was changed in 18 cases (33.3%) after accounting for the DTI/DTT results. Among 55 CSTs on which DsCS was performed, 46 (83.6%) were validated as spatially accurate by DsCS. The CST score and TCD were significantly correlated with postoperative muscle strength (r = -0.395, p < 0.001, and r = 0.275, p = 0.004, respectively) and postoperative mRS score (r = 0.430, p = 0.001, and r = -0.329, p = 0.015, respectively). The CST score was independently linearly associated with postoperative muscle strength (t = -2.461, p = 0.016) and the postoperative mRS score (t = 2.052, p = 0.046). CONCLUSIONS: DTI/DTT is a valuable tool in the surgical management of brainstem gliomas. With good accuracy, it can help optimize surgical planning, guide tumor resection, and predict the postoperative muscle strength and postoperative quality of life of patients.

A prediction of postoperative neurological deficits following intracranial aneurysm surgery using somatosensory evoked potential deterioration duration.

Although the application of somatosensory evoked potential (SSEP) in intracranial aneurysm surgery has been well demonstrated, the relationship between the duration of SSEP deterioration and postoperative neurological deficits (PNDs) is still not clear. The objectives of this study were (1) to detect the relationship between the SSEP deterioration duration and PND; and (2) detect the relationship between SSEP deterioration duration and postoperative computed tomography (CT) findings. Data from 587 patients were reviewed and 40 patients with SSEP deterioration were enrolled. Four patients presented irreversible disappearance and 36 patients presented reversible deterioration (including 9 [25%] patients with reversible reduction and 27 [75%] patients with reversible disappearance). In the patients with reversible SSEP deterioration, 17 patients had PNDs, and the SSEP deterioration duration was 42 ± 46 min, ranging from 5 to 180 min. Nineteen patients did not have PNDs, and their duration of SSEP deterioration was 11 ± 9 min (range 2-40 min). The SSEP deterioration duration significantly differed between patients with or without PND (P < 0.01). Eleven minutes is the optimal cut-off value of motor evoked potential change duration avoiding PND (area under the curve = 0.84). Patients with a SSEP deteriorating duration > 11 min had a significant higher incidence rate of abnormal CT finding postoperatively (p < 0.05). According to these results, we conclude that the duration of SSEP deterioration is extremely important to postoperative neurological function, and in order to avoid PND, the SSEP deterioration duration must not exceed 10 min. The SSEP deterioration duration is also associated with postoperative CT findings.

Hypoglossal-facial nerve 'side'-to-side neurorrhaphy using a predegenerated nerve autograft for facial palsy after removal of acoustic tumours at the cerebellopontine angle.

TRIAL DESIGN: Hypoglossal-facial nerve (HN-FN) neurorrhaphy is a method commonly used to treat facial palsy when the proximal stump of the injured FN is unavailable. Since the classic HN-FN neurorrhaphy method that needs to section the injured FN is not suitable for incomplete facial palsy, we investigated a modified method that consists of HN-FN 'side'-to-side neurorrhaphy, retaining the remaining or spontaneously regenerated FN axons while preserving hemihypoglossal function. METHODS: To improve axonal regeneration, we used for the first time a predegenerated sural autograft for performing HN-FN 'side'-to-side neurorrhaphy followed by postoperative facial exercise. We treated 12 patients who had experienced FN injury for 1-18 months as a result of acoustic tumour removal. All patients experienced facial grade V-VI paralysis according to the House-Brackmann scale, but their FN was anatomically preserved. No spontaneous facial reinnervation was detected before repair. RESULTS: Although we did not perform fresh nerve grafts and HN-FN 'side'-to-end neurorrhaphy as controls for ethical reasons, the reparative outcomes after nerve reconstruction were remarkable: functional improvements were detected as soon as 3 months after repair, House-Brackmann grade II or III FN functions were achieved in five and four patients, respectively, and there were no apparent signs of synkinesis. The three patients who experienced less satisfactory outcomes had exhibited facial palsy for more than 1 year accompanied by muscle atrophy, consistent with a need for rapid surgical intervention. CONCLUSIONS: Based on fundamental concepts and our experimental results, this new surgical method represents a major advance in the rehabilitation of FN injury. TRIAL REGISTRATION NUMBER: JS2013-001-02.

An improved chaos sparrow search algorithm for UAV path planning.

This study suggests an improved chaos sparrow search algorithm to overcome the problems of slow convergence speed and trapping in local optima in UAV 3D complex environment path planning. First, the quality of the initial solutions is improved by using a piecewise chaotic mapping during the population initialization phase. Secondly, a nonlinear dynamic weighting factor is introduced to optimize the update equation of producers, reducing the algorithm's reliance on producer positions and balancing its global and local exploration capabilities. In the meantime, an enhanced sine cosine algorithm optimizes the update equation of the scroungers to broaden the search space and prevent blind searches. Lastly, a dynamic boundary lens imaging reverse learning strategy is applied to prevent the algorithm from getting trapped in local optima. Experiments of UAV path planning on simple and complex maps are conducted. The results show that the proposed algorithm outperforms CSSA, SSA, and PSO algorithms with a respective time improvement of 22.4%, 28.8%, and 46.8% in complex environments and exhibits high convergence accuracy, which validates the proposed algorithm's usefulness and superiority.

A new method for unmanned aerial vehicle path planning in complex environments.

To solve the problems of UAV path planning, such as low search efficiency, uneven path, and inability to adapt to unknown environments, this paper proposes A double-layer optimization A* and dynamic window method for UAV path planning. Firstly, the neighboring node clip-off rule is defined to optimize the node expansion mode of the A* algorithm, and the obstacle coverage model is designed to dynamically adjust the heurizing function of the A* algorithm to improve the path search efficiency. Then, the Bresenham algorithm is adopted for collision detection and critical path nodes are extracted to significantly reduce the number of path turning points. Secondly, a new tracking index is proposed to optimize the evaluation function of the dynamic window method to make the local path fit the global path further. By detecting the dangerous distance, the dynamic adaptive method of evaluation function weight is designed to improve the fixed weight of the dynamic window method. Finally, the key turning point of optimizing the A* algorithm is taken as the temporary target point to improve the DWA algorithm, and the local part follows the global part, and the fusion of the two algorithms is realized. Simulation results show that the proposed method can significantly improve the efficiency and smoothness of mobile robot path planning, enhance the real-time obstacle avoidance and adaptive ability of unknown environments, and better meet the requirements of complex planning tasks.

Rapid Plasma Electrolytic Oxidation Synthesis of Intermetallic PtBi/MgO/Mg Monolithic Catalyst for Efficient Removal of Organic Pollutants.

The intermetallic PtBi/MgO/Mg monolithic catalyst was first prepared using non-equilibrium plasma electrolytic oxidation (PEO) technology. Spherical aberration-corrected transmission electron microscope (ACTEM) observation confirms the successful synthesis of the PtBi intermetallic structure. The efficiency of PtBi/Mg/MgO catalysts in catalyzing the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the presence of NaBH4 was demonstrated. The activity factor for the catalyst is 31.8 s-1 g-1, which is much higher than reported values. In addition, the resultant catalyst also exhibits excellent catalytic activity in the organic pollutant reaction of p-nitrobenzoic acid (p-NBA) and methyl orange (MO). Moreover, benefiting from ordered atomic structures and the half-embedded PtBi nanoparticles (NPs), the catalyst demonstrates excellent stability and reproducibility in the degradation of 4-NP. This study provides an example of a simple method for the preparation of intermetallic structures as catalysts for organic pollutant degradation.

Utility of Dual Monitoring of the Lower Cranial Nerve Motor-Evoked Potentials Threshold Level Criterion to Predict Swallowing Function in Skull Base and Brainstem Surgery.

PURPOSE: Evaluate the value of bilateral final/baseline threshold level changes of lower cranial nerve MEPs in postoperative swallowing function deterioration prediction. METHODS: Bilateral lower cranial nerve motor-evoked potentials (MEPs) were recorded in 51 patients who underwent treatment for skull base and brainstem tumors. Corkscrew-like electrodes were positione 2 cm below C3/C4 and Cz. The MEPs were recorded from different muscle groups, including the posterior pharyngeal wall muscle, tongue muscle, genioglossus muscle, and cricothyroid muscle through paired needle electrodes. Swallowing function was assessed clinically using the Mann Assessment of Swallowing Ability score before and after the procedure at 7 days, 1 month, and 3 months. RESULTS: Bilateral final/baseline threshold level increases in lower cranial nerve MEPs under the dual monitoring were significantly correlated with postoperative swallowing function deterioration ( r = 0.660 at 7 days, r = 0.735 at 1 month, and r = 0.717 at 3 months; p < 0.05). Bilateral final/baseline threshold level changes of more than 20% were recorded in 23 of the 51 patients, with 21 patients experiencing swallowing function deterioration postoperatively. The other 28 patients had bilateral threshold level changes of less than 20%, with 26 patients maintaining or improving their swallowing function, and 12 of those patients presented transient deterioration of swallowing function in the early postoperative period. CONCLUSIONS: Dual monitoring of lower cranial nerves and their different muscle groups MEPs was a safe and effective way to predict postoperative swallowing function. An increase in bilateral final/baseline threshold level change of more than 20% was predictive of permanent swallowing deterioration, especially in patients with poor swallowing function preoperatively.

Application and improvement methods of sludge alkaline fermentation liquid as a carbon source for biological nutrient removal: A review.

Alkaline fermentation can reduce the amount of waste activated sludge and prepare sludge alkaline fermentation liquid (SAFL) rich in short-chain fatty acids (SCFAs), which can be used as a high-quality carbon source for the biological nutrient removal (BNR) process. This review compiles the production method of SAFL and the progress of its application as a BNR carbon source. Compared with traditional carbon sources, SAFL has the advantages of higher efficiency and economy, and different operating conditions can influence the yield and structure of SCFAs in SAFL. SAFL can significantly improve the nutrient removal efficiency of the BNR process. Taking SAFL as the internal carbon source of BNR can simultaneously solve the problem of carbon source shortage and sludge treatment difficulties in wastewater treatment plants, and further reduce the operating cost. However, the alkaline fermentation process results in many refractory organics, ammonia and phosphate in SAFL, which reduces the availability of SAFL as a carbon source. Purifying SCFAs by removing nitrogen and phosphorus, directly extracting SCFAs, or increasing the amount of SCFAs in SAFL by co-fermentation or combining with other pretreatment methods, etc., are effective measures to improve the availability of SAFL.

The Utility of Motor Evoked Potential Monitoring for Predicting Postoperative Motor Deficit in Patients With Insular Gliomas.

PURPOSE: Motor evoked potential (MEP) monitoring has been widely applied in various neurosurgical operations. This study aimed to assess the predictive value of MEP monitoring for postoperative motor deficit (PMD) in patients with insular gliomas. METHODS: Demographic and clinical data, MEP monitoring data, and follow-up data of 42 insular glioma patients were retrospectively reviewed, and 40 patients were finally enrolled. The value of MEP monitoring for predicting PMD was assessed with sensitivity, specificity, and false-positive/false-negative rates. Binary multivariate logistic regression analysis was performed to further identify the predictive value of MEP monitoring. RESULTS: Statistical analysis showed that irreversible MEP changes, but not all MEP changes, were more effective in predicting PMD. The sensitivity and specificity of irreversible MEP changes for predicting long-term PMD were 85.71 and 93.94%, whereas the false-positive and -negative rates were 25.00 and 3.12% respectively. In addition, irreversible MEP changes were identified as the only independent predictor for long-term PMD (odds ratio, 101.714; 95% confidence interval, 6.001-1724.122; p = 0.001). CONCLUSIONS: MEP monitoring has been proven to be feasible in insular glioma surgery. Irreversible MEP changes showed good performance in predicting PMD. Their absence can offer an optimistic expectation for the long-term motor outcome. The findings can provide the surgical team with a more effective interpretation of MEP changes and contribute to exploring tailored MEP warning criteria.

Removal of PFASs from water by carbon-based composite photocatalysis with adsorption and catalytic properties: A review.

Per- and polyfluoroalkyl substances (PFASs) are a class of persistent organic pollutants widely distributed in aquatic environments. The adsorption and photocatalytic methods have been widely used to remove PFASs in water because of their respective advantages. Still, they have apparent defects when used alone. Therefore, the adsorption and photocatalytic technologies are combined through suitable preparation methods, and the excellent properties of the two are used to synergize the treatment of organic pollutants. This strategy of "concentrating" pollutants and then degrading them in a centralized manner plays an essential role in removing trace PFASs. Nevertheless, a review focusing on this kind of adsorption photocatalyst system is lacking. This review will fill this gap and provide a reference for developing a carbon-based composite photocatalyst. Firstly, different carbon-based composite photocatalysts are reviewed in detail, focusing on the differences in various composite materials' excellent adsorption and catalytic properties. Secondly, the factors influencing the removal effect of carbon-based composite photocatalysts are discussed. Thirdly, the removal mechanism of carbon-based composite photocatalysts is summarized in detail. The removal process involves two steps: adsorption and photodegradation. The adsorption process involves multiple cooperative adsorption mechanisms, and photocatalytic degradation includes oxidative and reductive degradation. Fourthly, the comparison of adsorption-photocatalysis with common treatment techniques (including removal rate, range of adaptation, cost, and the possibility of expanding application) is summarized. Finally, the prospects of carbon-based composite photocatalysts for repairing PFASs are given by evaluating the performance of different composites.

The Application of Regional Cerebral Oxygenation Monitoring in the Prediction of Cerebral Hypoperfusion During Carotid Endarterectomy.

BACKGROUND: The aim of this study was to assess the diagnostic ability of near-infrared spectroscopy-monitored regional cerebral oxygen saturation (rSO2) to detect cerebral hypoperfusion during internal carotid artery (ICA) clamping compared with motor and somatosensory evoked potential (EP) monitoring. METHODS: This prospective study recruited consecutive patients undergoing carotid endarterectomy under general anesthesia. Significant EP changes (defined as >50% decrease in ipsilateral somatosensory EP amplitude or disappearance of contralateral motor EP on >2 consecutive stimulations) during ICA clamping were considered a warning sign for cerebral hypoperfusion. If significant EP changes occurred, the amplitude of the EPs and simultaneous rSO2 values were recorded before therapeutic intervention. The relationship between reductions in rSO2 and EP amplitudes was analyzed using Spearman rank-correlation analysis. Receiver operating characteristic curve analysis was used to calculate the optimal cutoff value for the relative reduction in rSO2. False-positive rates were evaluated according to immediate postoperative motor outcomes. RESULTS: A total of 203 patients were included for analysis, of whom 23 developed significant EP changes during ICA clamping. There was a positive relationship between decreases in EP amplitude and rSO2 (R2=0.15, P=0.02). A rSO2 reduction ≥16% from baseline had the optimal diagnostic performance for the detection of cerebral hypoperfusion (area under the receiver operating characteristic curve=0.82; 95% confidence interval: 0.76-0.87). The false-positive rate was 8.9%. CONCLUSIONS: Decreases in rSO2 correlated with decreases in EP amplitude during ICA clamping. A relative reduction in rSO2 ≥16% could serve as a warning for clamping-associated cerebral hypoperfusion. The 8.9% false-positive rate is a potential clinical limitation of the use of rSO2 to predict postoperative neurological deficits.

Incidence of ischemic complications and technical nuances of arteries preservation for insular gliomas resection.

Introduction: Insular gliomas have complex anatomy and microvascular supply that make resection difficult. Furthermore, resection of insular glioma is associated with a significant risk of postoperative ischemic complications. Thus, this study aimed to assess the incidence of ischemic complications related to insular glioma resection, determine its risk factors, and describe a single surgeon's experience of artery-preserving tumor resection. Methods: We enrolled 75 consecutive patients with insular gliomas who underwent transcortical tumor resection. Preoperative and postoperative demographic, clinical, radiological [including diffusion-weighted imaging (DWI)], intraoperative neurophysiological data, and functional outcomes were analyzed. Motor evoked potentials (MEPs) and radiological characteristics like the relationship between the proximal segment of the lateral lenticulostriate arteries (LLSAs) and the tumor, the flat inner edge sign (the inner edge of the insular glioma is well-defined) or obscure inner edge sign, the distance between the lesion and posterior limb of the internal capsule and the invasion of the superior limiting sulcus by the tumor were analyzed. Strategies such as "residual triangle," "basal ganglia outline reappearance," and "sculpting" technique were used to preserve the LLSAs and the main branches of M2 for maximal tumor resection according to the Berger-Sinai classification. Results: Postoperative DWI showed acute ischemia in 44 patients (58.7%). Moreover, nine patients (12%) had developed new motor deficits, as determined by the treating neurosurgeons. The flat inner edge sign [odds ratio (OR), 0.144; 95% confidence interval (CI), 0.024-0.876) and MEPs (>50%) (OR, 18.182; 95% CI, 3.311-100.00) were significantly associated with postoperative core ischemia, which affected the posterior limb of the internal capsule or corona radiata. Conclusions: Insular glioma resection was associated with a high incidence of ischemia, as detected by DWI, as well as new motor deficits that were determined by the treating neurosurgeons. Insular glioma patients with obscure inner edge signs and intraoperative MEPs decline >50% had a higher risk of developing core ischemia. With our strategies, maximal safe resection of insular gliomas may be achieved.

Prediction of postoperative motor deficits using motor evoked potential deterioration duration in intracranial aneurysm surgery.

OBJECTIVE: The study aimed to investigate the predictive value of motor evoked potential (MEP) deterioration duration for postoperative motor deficits in patients undergoing intracranial aneurysm surgery. METHODS: Data from 587 patients were reviewed and 92 patients with MEP deterioration were enrolled. MEP deterioration duration was compared between patients with and without postoperative motor deficits. Receiver operating characteristic (ROC) curve analysis was performed to define the threshold value for predicting postoperative motor deficit risk. Additionally, the association between MEP deterioration duration and postoperative CT findings was explored. RESULTS: Patients with postoperative motor deficits had a significantly longer MEP deterioration duration (p < 0.01). An MEP deterioration duration greater than or equal to 13 min was identified as an independent predictor of immediate (p < 0.01), short-term (p < 0.01), and long-term postoperative motor deficits (p < 0.05). There was no significant association between MEP deterioration duration and new CT abnormalities. CONCLUSION: MEP deterioration duration could be used for predicting intracranial aneurysm surgical outcome. SIGNIFICANCE: The study first proposed a threshold value of MEP deterioration duration (13 min) for predicting the risk of postoperative motor deficits in patients undergoing intracranial aneurysm surgery.

Neuronavigation-Guided Corticospinal Tract Mapping in Brainstem Tumor Surgery: Better Preservation of Motor Function.

OBJECTIVE: To evaluate a new technique in brainstem surgery, neuronavigation (NN)-guided corticospinal tract (CST) mapping, in a retrospective study of patients undergoing brainstem tumor surgery. METHODS: We studied 40 patients with a brainstem tumor who were enrolled in this study. Patients whose worst preoperative muscle strength of the 4 limbs was greater than 3 levels from normal on the Lovett scale were divided into 2 groups: a treatment group of 21 patients who underwent NN-guided CST mapping and routine intraoperative neurophysiology monitoring (IONM) and a control group of 19 patients who underwent routine NN and IONM. Preoperative muscle strength and postoperative (day 90 postsurgery) muscle strength were assessed and compared between the 2 groups. RESULTS: In the NN-guided CST mapping group, 3 patients (14.3%) had a decrease in muscle strength by 1 level postoperatively, and no patient experienced a decrease of >1 level. In the control group, 4 patients (21.1%) had a 1-level decrease in muscle strength, and 5 (26.3%) had a decrease of >1 level. Patients in the NN-guided CST mapping group had significantly better surgical outcomes compared with those in the control group (P = 0.018, Fisher exact test). CONCLUSIONS: Brainstem tumor resection using NN-guided CST mapping achieved better preservation of motor function compared with routine NN and IONM. NN-guided CST mapping not only decreased the difficulty of the surgery, but also significantly improved the efficiency of surgery.

Comparison of the effects of etomidate and propofol combined with remifentanil and guided by comparable BIS on transcranial electrical motor-evoked potentials during spinal surgery.

BACKGROUND: Transcranial electrical motor-evoked potentials (TceMEPs) can provide early warning of possible motor compromise during surgery. There are fewer reports comparing the effects of etomidate and propofol infusion on TceMEPs when used for the maintenance of anesthesia and guided by comparable values of bispectral index (BIS) during spinal surgery. METHODS: Thirty-three patients scheduled for spinal surgery were randomly divided into 2 groups: propofol (PR, n=18) and etomidate (ER, n=15). Anesthesia was maintained with either propofol or etomidate combined with remifentanil. The infusion rates for propofol or etomidate were guided by the BIS value, which was maintained between 40 and 45. TceMEPs were conducted by stimulating needles placed at C1 and C2; recordings were made by measuring myogenic responses from the upper extremity abductor pollicis brevis muscles using needle electrodes. The threshold for eliciting a response, amplitudes, and latencies of TceMEPs, were recorded at 30, 60, 90, and 120 minutes after the induction of anesthesia. The cortisol levels were measured at 2 and 24 hours after induction. RESULTS: The voltage threshold needed to enlist TceMEPs in the ER group was significantly lower than that in the PR group (142±20 vs. 172±23 V, P=0.005). The amplitudes of TceMEPs were higher in the ER group than those in the PR group (P<0.05), whereas the latencies were shorter in the ER group than those in the PR group (P<0.05) at all study time points. Cortisol levels at all study time points were within the normal range. CONCLUSIONS: Etomidate has more favorable effects than propofol during the monitoring of TceMEPs under comparable BIS levels.