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Large components are crucial in modern industrial applications, especially for internal gap monitoring and specific assembly methods. This paper examines the assembly of hydroelectric generator rotors and stators, introducing a spatial relative position monitoring system using multiple sensors. A dedicated position monitoring program is designed, and error sources within the system are thoroughly explored. Detailed error analysis and modeling reveal that verticality and angular errors significantly impact monitoring accuracy. To address this, two error control methods are proposed to effectively mitigate these issues, ensuring precise assembly of large components. [ABSTRACT FROM AUTHOR]

The minimum resolvable temperature difference (MRTD) at which a four-rod target can be resolved is a critical parameter used to assess the comprehensive performance of thermal imaging systems, which is important for technological innovation in military and other fields. Recently, there have been some attempts to use an automatic objective approach based on deep learning to take the place of the classical manual subjective MRTD measurement approach, which is strongly affected by the psychological subjective factors of the experimenter and is limited in accuracy and speed. However, the scale variability of four-rod targets and the low pixels of infrared thermal cameras have turned out to be a challenging problem for automatic MRTD measurement. We propose a multiscale deblurred feature extraction network (MDF-Net), a backbone based on a yolov5 neural network, in an attempt to solve the aforementioned problem. We first present a global attention mechanism (GAM) attention module to represent strong images of the four-rod targets. Next, a Rep VGG module is introduced to decrease the blur. Our experiments show that the proposed method achieves the desired effect and state-of-the-art detection results, which innovatively improve the accuracy of four-rod target detection to 82.3% and thus make it possible for the thermal imagers to see further and to respond faster and more accurately. [ABSTRACT FROM AUTHOR]

In this paper, a new six dimensional memristor chaotic system is designed by combining the chaotic system with a memristor. By analyzing the phase diagram of the chaotic attractors, eleven different attractors are found, including a multi-wing attractor and symmetric attractors. By analyzing the equilibrium point of the system, it is proven that the system has the property of a hidden chaotic attractor. The dynamic behavior of the system when the three parameters change is analyzed by means of LEs and a Bifurcation diagram. Other phenomenon, such as chaos degradation, coexistence of multiple attractors and bias boosting, are also found. Finally, the simulation on the DSP platform also verifies the accuracy of the chaotic system simulation. The theoretical analysis and simulation results show that the system has rich dynamical characteristics; therefore, it is suitable for secure communication and image encryption and other fields. [ABSTRACT FROM AUTHOR]

Neuroprotective effects of dexmedetomidine are reported in preclinical and clinical studies but evidence regarding the postoperative neurocognitive function is not as clear. This study performed a meta-analysis on outcomes of studies which examined neurocognitive performance by using valid assessment tools before and after perioperative dexmedetomidine treatment. Literature was searched in several electronic databases and studies were selected by following précised inclusion criteria. Meta-analyses of mean differences in percent changes from baseline in neurocognitive assessment scores were carried out and subgroup analyses were performed. Eighteen studies were included. Initial dose of dexmedetomidine (mean ± SD) was 1.28 ± 0.97 μg/kg and maintenance dose was 0.41 ± 0.11 μg/kg per hour. In healthy volunteers, there was no significant difference in the neurocognitive performance between dexmedetomidine and controls/comparators (mean difference (95% confidence interval ( CI)): −12.72 (−50.25, 24.80) %; P = 0.51). Perioperative dexmedetomidine treatment was associated with significantly better neurocognitive performance in comparison with saline (mean difference (95% CI): 9.10 (3.03, 15.16) %; P = 0.003) as well as with comparator anaesthetics (mean difference: 5.50 (0.15, 10.86) %; P = 0.04) treated patients. In the submeta-analyses of studies which utilized neurocognitive assessment tools other than Mini-Mental State Examination (mean difference: 6.66 (-3.42, 16.74); P = 0.20) or studies with patients under 60 years of age (mean difference: 7.48 (−3.00, 17.96); P = 0.16), the differences were not significant between dexmedetomidine- and saline-/comparator-treated patients. Perioperative dexmedetomidine treatment is associated with significantly better neurocognitive function postoperatively in comparison with both saline controls and comparator anaesthetics (predominantly midazolam). [ABSTRACT FROM AUTHOR]

The Qinghai–Tibetan Plateau is a very large land unit and an important terrestrial ecosystem within the Eurasian continent. Because of the harsh climate associated with the high altitude, alpine meadows on the plateau are susceptible to degradation from overgrazing. For this region, and for other alpine meadow pastures internationally, there is a need to define the sustainable stocking rate, to develop sound policy pertaining to future land use. Here we report biomass and liveweight gain per animal and per ha for pastures grazed by yaks at high, medium, or low stocking rates over 4 growing seasons from 2010 to 2013. Measures of herbage nutritive value are reported. The influence of inter-year variation in precipitation on standing herbage biomass was also evaluated. Higher precipitation increased standing herbage biomass and herbage nutritive value, indicating that vegetation suffered summer water deficit even in this environment. The sustainable stocking rate in this environment was determined to be approximately 1 yak ha-1 (grown from 80 kg to 120 kg liveweight in 90 d). At this stocking rate, yak weight gain per ha was 88% of that achieved at higher stocking rates typically used by farmers, but with little or no evidence of land degradation. [ABSTRACT FROM AUTHOR]

Objective This study aims to evaluate the feasibility of intraoperative composite target-controlled infusion (TCI) anesthesia application using remifentanil hydrochloride with etomidate in patients with severe burns, as monitored by Narcotrend. Methods A total of 40 patients with severe burns with eschar excisions and skin grafts were randomly and equally grouped into the etomidate (E) and the propofol groups (P). Anesthesia was induced and maintained by a remifentanil hydrochloride TCI combined with etomidate or propofol. The depth of anesthesia and other relevant indicators were recorded through intraoperative electroencephalogram monitoring using a Narcotrend monitor. Results No statistically significant differences were observed between the drug withdrawal times, eye opening requirements, or orientation recoveries of the two groups ( P > 0.05). The cortisol and aldosterone levels in group E were significantly lower than those in group P 24 h post operation ( P < 0.05). No significant differences between the number of operations, hospitalization duration, mean arterial pressure, heart rate, and postoperative adverse reaction incidence of the two groups were observed at each time point ( P > 0.05). Conclusion The application of a composite remifentanil hydrochloride combined with etomidate TCI is feasible for the early eschar excision in patients with severe burns. [ABSTRACT FROM AUTHOR]

Purpose: To compare perioperative parameters, clinical outcomes, radiographic parameters, and complication rates of segmental anterior cervical corpectomy and fusion (sACCF) plus preservation of middle vertebrae with those of cervical laminectomy plus fusion (CLF) in 67 patients with 4-level cervical spondylotic myelopathy (CSM). Methods: Between July 2006 and May 2012, 67 consecutive patients [42 males and 25 females; mean age 57.8 years (range 34-77 years)] with 4-level CSM who underwent surgery and were followed for more than 1 year were enrolled in this study and divided into sACCF and CLF groups. The study compared perioperative parameters; surgery-related and instrumentation- and graft-related complication rates; clinical parameters; patient satisfaction; and radiologic parameters. Results: Significant improvements were seen from preoperative to postoperative in both groups for all three measures of clinical outcome; between-group comparison revealed no significant difference for two of the three measures and significantly better scores for the CLF group in the third. Satisfaction was rated as excellent or good by 79.5 % of the sACCF group and 71.4 % of the CLF group, which was not a significant difference. Mean postoperative cervical lordosis was significantly greater in the sACCF group than in the CLF group. Blood loss and operative time were significantly greater in the CLF group than in the sACCF group and complication rate significantly lower for the sACCF group. Conclusions: sACCF with preservation of middle vertebrae is a safe, reliable, and effective alternative procedure for the treatment of 4-level CSM. [ABSTRACT FROM AUTHOR]

Background: Topical anesthesia is a crucial step in awake endotracheal intubation for providing favorable intubation conditions. The standard of care technique for awake intubation at our institution, which consists of oropharyngeal tetracaine spray, can result in inadequate mucosal anesthesia. Therefore, we sought to compare the effectiveness of dyclonine hydrochloride mucilage to the standard of care tetracaine in achieving anesthesia of the upper airways for awake endotracheal intubation. Methods: This is a randomized, assessor-blinded, prospective study. From Jun. 1st, 2019 to Aug. 1st, 2019, patients scheduled for either endoscopic submucosal dissection or peroral endoscopic myotomy were enrolled and randomly allocated into two groups after obtaining written informed consent: patients allocated to novel awake intubation care (Group N-AIC) received a single administration of oral dyclonine hydrochloride mucilage, whereas patients allocated to standard awake intubation care (Group S-AIC) received three oropharyngeal tetracaine sprays before transcricoid tetracaine injection before awake intubation. Mean arterial pressure (MAP), which was the primary outcome of this study, as well as heart rate (HR) were recorded throughout the procedure and compared between the two groups. Feeling of numbness, nausea, and intubation conditions after topical anesthesia were also assessed. Results: Sixty patients were enrolled and completed the study. Baseline MAP and HR were similar between the two groups. However, hemodynamic responses to intubation and gastrointestinal endoscopy, especially MAP, were significantly less elevated in Group N-AIC. The degree of numbness of the oropharyngeal mucosa after topical anesthesia did not differ between the two groups, neither did the feeling of nausea during laryngoscopy. The amount of pharyngeal secretions before intubation was less in Group N-AIC. Total intubation time was significantly shorter in Group N-AIC when compared to Group S-AIC (18.4 ± 2.86 vs. 22.3 ± 6.47, P < 0.05). Extubation bucking was significantly less frequent in Group N-AIC (13.3% vs. 76.7%). Patients received in Group N-AIC had a lower rate of post-extubation sore throat compared to Group S-AIC (6.7% vs. 43.3%). No adverse side effects attributable to either tetracaine or dyclonine were observed in this study. Conclusions: In awake endotracheal intubation, novel care using oral dyclonine hydrochloride mucilage can provide more favorable mucosal anesthesia and better intubation conditions compared to standard of care practice using oropharyngeal tetracaine spray. Trial registration: ChiCTR1900023151. Date of registration: May 14th, 2019. [ABSTRACT FROM AUTHOR]

Purpose: The presence of obesity poses a challenge for clinical and administrative staff in the peri-operative setting. Evidence indicates that obesity may increase peri-operative complications. However, data on resource utilization in patients undergoing total knee and hip arthroplasty remain rare. Using national data, we sought to determine whether increasing levels of patient obesity is associated with greater resource utilization. We hypothesized that patient care in individuals with a body mass index (BMI) greater than 40 is associated with longer operative and anaesthetic times, longer hospital stays, and greater readmission rates.Methods: We utilized national data from the National Surgical Quality Improvement Project and identified patients who underwent primary total knee arthroplasty (TKA) and total hip arthroplasty (THA). Patients were divided into three groups according to their BMI (18.5 BMI < 30, 40 BMI < 45, and 45 BMI). The groups were compared regarding associated operating room utilization, length of stay, and readmission rates.Results: Our study showed that TKA and THA patients with higher BMI required significantly longer operation-related times and had higher total length of hospital stay. Higher BMI patients also carried higher odds of readmissions within 30 days in both TKA and THA groups.Conclusion: We conclude that BMI status needs to be considered for both medical and economic reasons by health care institutions and payers, in order to make prudent decisions in a world where health care expenses are rising rapidly alongside the increasing obesity epidemic, and resources are becoming increasingly scarce. [ABSTRACT FROM AUTHOR]

(1) Background: Anesthetic sedatives are widely used for bronchoscopy, and controversy surrounds the safety and efficacy of dexmedetomidine compared to other sedatives. The aim of this study is to evaluate the safety and efficacy of dexmedetomidine in bronchoscopy through a systematic review. (2) Methods: PubMed, Embase, Google Scholar, and Cochrane Library electronic databases were searched for a randomized controlled study of dexmedetomidine (Group D) or other sedative drugs (Group C) for bronchoscopy. Data extraction, quality assessment, and risk of bias analysis were performed in accordance with the preferred reporting items for systematic review and meta-analysis requirements. Meta-analysis was performed using RevMan 5.2. (3) Results: Nine studies were included, with a total of 765 cases. Compared to Group C, the incidence of hypoxemia (OR = 0.40, 95% CI (0.25, 0.64) p = 0.0001, I2 = 8%) and tachycardia (OR = 0.44, 95% CI (0.26,0.74), p = 0.002, I2 = 14%) were lower, but bradycardia (OR = 3.71, 95% CI (1.84, 7.47), p = 0.0002, I2 = 0%) was higher in Group D; no significant difference was observed in other outcome indicators. (4) Conclusions: Dexmedetomidine reduces the incidence of hypoxemia and tachycardia during bronchoscopy but is more likely to provoke bradycardia. [ABSTRACT FROM AUTHOR]

Abstract: A novel two-dimensional water layer which is trapped in a one-dimensional neodymium-organic arrays, [Nd2(BC)2(OX)(H2O)6] n ·10nH2O (BC2− =1,3-benzenedicarboxylate anion and ), is reported. There are puckered 6-, 12- and 16-membered rings existing in the water layer. The cyclic 6- and 12-membered rings in turn fuse together to generate the water tape, namely T6(3)12(3)6(2). The water layer is formed via the assembly of the T6(3)12(3)6(2) water tapes. [Copyright &y& Elsevier]

Introduction: Postoperative delirium is one of the most common and dangerous psychiatric complications after hip surgery. The aim of this study was to investigate the incidence of postoperative delirium in elderly patients after hip fracture surgery and to identify risk factors for such, as part of developing a risk stratification index (RSI) system to predict a patient's risk of postoperative delirium. Methods: Elderly patients (aged 65 years or older) with hip fractures who had received surgical treatment in our hospital between March 2018 and December 2019 were retrospectively included. Clinical data were collected, and multivariate logistic regression analysis was performed to investigate the relevant risk factors of postoperative delirium. An RSI system was developed based on factors identified in the regression analysis. Results: Of 272 patients included, 52 (19.12%) experienced postoperative delirium. Drinking history (> 3/ week), the perioperative lactic acid level (Lac > 2 mmol/L), postoperative visual analog score (VAS) > 3, American Society of Anesthesiologists (ASA) physical status > II, application of the bispectral index, and preoperative diabetes were independent risk factors of postoperative delirium. When RSI ≥ 5, the rate of postoperative delirium significantly increased (p <.05). Conclusion: The RSI system developed here can safely guide postoperative outcomes of elderly patients with hip fractures, and RSI ≥ 5 may be able to predict the onset of postoperative delirium. [ABSTRACT FROM AUTHOR]

Introduction: Low serum albumin is associated with higher perioperative complications following total hip arthroplasty (THA). The distinct threshold for a significant rise in perioperative complications has not been defined for THA. The purpose of this study was to define the threshold at which perioperative complications rise after THA. Methods: We analysed the American College of Surgeons NSQIP database from 2006 to 2013. Our study cohort included unilateral primary THA with reported preoperative albumin levels. Patients were stratified by albumin level. We analysed mortality and 6 composite complication variables (any complication, any complication without transfusion, wound infection, systemic infection, cardiac/pulmonary complications, and any major complication). All data analysis was executed in STATA statistical software. Multivariable logistic regression analysis was used to adjust for odds ratios. Results: The final cohort included 24,586 patients who were stratified based upon serum albumin levels. Odds ratios after multivariable regression adjustment for age, gender, race, body mass index, ASA classification, and Charlson Comorbidity Index indicated a trend to elevated odds of complication for all composite complications (3 of which were statistically significant) when serum albumin level was <3.0 g/dL. Conclusion: Low serum albumin is associated with increased perioperative complications following THA. The threshold associated with an increase in major perioperative complications appears to be an albumin level of <3.0 g/dL. With attempts to correct modifiable risk factors prior to surgery, the threshold value at which perioperative complications increase is important to define. [ABSTRACT FROM AUTHOR]

The Moderate Resolution Imaging Spectroradiometer (MODIS)/Terra daily snow cover product MOD10A1 was compared with in situ climate station measurements and a snow map generated from Landsat Enhanced Thematic Mapper Plus (ETM+) data. Snow-covered area (SCA) dynamics were assessed using the MODIS 8-day snow cover composite product MOD10A2 for the 2001-2005 snow seasons in northern Xinjiang, China. The results indicate that the snow-mapping agreement between MODIS daily snow maps and surface observations is high at 94.6% over the four snow seasons under clear-sky conditions. The snow classification accuracy in a mountainous area was lower than that in a plain area and caused higher omission errors, probably resulting in an underestimation of the SCA. The omission errors were mainly determined by snow depth, land cover types, the terrain and mixed pixels. The cloud agreement was 95.9%, and approximately 4.1% of cloud was misclassified as snow when the sky view at the climate stations was covered by clouds. An improvement was found in suppressing clouds using the 8-day products, with MOD10A2 reducing about 88.4% of the average cloud cover compared with MOD10A1. SCA in northern Xinjiang retrieved using MOD10A2 shows a clear seasonal trend. The air temperature plays an important role in the fractional SCA, and the spatial distribution of the snow cover differs considerably in the various areas in the northern Xinjiang region. [ABSTRACT FROM AUTHOR]

Abstract: The fault diagnosis of rolling element bearing is important for improving mechanical system reliability and performance. When localized fault occurs in a bearing, the periodic impulsive feature of the vibration signal appears in time domain, and the corresponding bearing characteristic frequencies (BCFs) emerge in frequency domain. However, in the early stage of bearing failures, the BCFs contain very little energy and are often overwhelmed by noise and higher-level macro-structural vibrations, an effective signal processing method would be necessary to remove such corrupting noise and interference. In this paper, a new hybrid method based on optimal Morlet wavelet filter and autocorrelation enhancement is presented. First, to eliminate the frequency associated with interferential vibrations, the vibration signal is filtered with a band-pass filter determined by a Morlet wavelet whose parameters are optimized by genetic algorithm. Then, to further reduce the residual in-band noise and highlight the periodic impulsive feature, an autocorrelation enhancement algorithm is applied to the filtered signal. In the enhanced autocorrelation envelope power spectrum, only several single spectrum lines would be left, which is very simple for operator to identify the bearing fault type. Moreover, the proposed method can be conducted in an almost automatic way. The results obtained from simulated and practical experiments prove that the proposed method is very effective for bearing faults diagnosis. [Copyright &y& Elsevier]

Monitoring and estimating potential snow disasters in pastoral areas of northern Xinjiang Province are important for decision-making in hazard reduction and prevention. In this paper, four scenes of NOAA/AVHHR (Advanced Very high Resolution Radiometer) images were combined with ground observation data in the north of Xinjiang Province to establish a model for monitoring snow depth. Using a linear spectral decomposition method, the pixel-based snow coverage and snow classification were studied. The spatial characteristics of snow, grassland, animal and climate factors were used to develop two new quantified indices for estimating the potential snow hazard grade and for integrated evaluation of snow disasters to grassland animal husbandry. The criteria for snow hazard grade and snow disaster evaluation were established. Results indicated that: (i) a pixel-based index K1, based on grassland yield, animal capacity, utilisable grassland area coefficient and seasonal grazing utilisation scenarios, can be quantitatively integrated to reflect the grassland capability of resisting snow disasters; (ii) the snow hazard index (K) systematically expresses the spatial and temporal changes of grassland and snow cover, and analyses, and predicts and evaluates the snow hazard grade under conditions where climatic and animal husbandry information may be unavailable during snow disasters. This index plays an important role in studies on early warning of snow hazard in pastoral areas; (iii) the integrated snow disaster evaluation index (E) and related classification criteria reflect the details of snow disaster magnitude in temporal and spatial scales, which provide the basic information for dynamic monitoring and integrated evaluation on snow disasters in pastoral areas. [ABSTRACT FROM AUTHOR]