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Abstract Background To explore the independent association between lumbar endplate damage and bone mineral density (BMD) in patients with degenerative disc disease (DDD). Methods This retrospective investigation was based out of a prospectively collected database from the Affiliated Kunshan Hospital of Jiangsu University. Data from 192 DDD patients, collected between December 2018 and January 2022, were chosen for the final analysis. The average total endplate score (TEPS) of lumbar(L) 1-L4 was assessed by magnetic resonance imaging (MRI), and represents the extent of endplate damage. Osteoporosis severity was assessed via the L1-L4 BMD evidenced by dual-energy x-ray absorptiometry (DXA). Other analyzed information included gender, age, body mass index (BMI), and osteophyte score (OSTS). Uni- and multivariate linear regression analyses were employed to evaluate the association between average TEPS and BMD of L1-L4. Moreover, the generalized additive model (GAM) was employed for non-linear association analysis. Results Upon gender, age, BMI, and OSTS adjustments, a strong independent inverse relationship was observed between average TEPS and BMD (β, -0.021; 95% CI, -0.035 to -0.007, P-value = 0.00449). In addition, the gender stratification analysis revealed a linear relationship in males, and a non-linear relationship in females. Specifically, there was a significantly stronger negative relationship between average TEPS and BMD in females, when the average TEPS was 3.75, the relationship did not reach significance (β, 0.007; 95% CI, -0.012 to 0.027; P-value = 0.4592). Conclusions This study demonstrated the independent negative association between average TEPS and BMD values of L1-L4. Upon gender stratification, a linear relationship was observed in males, and a non-linear association in females. The findings reveal that patients with osteoporosis or endplate damage require more detailed examinations and treatment regimen.

Abstract This paper reviews China’s future fossil fuel supply from the perspectives of physical output and net energy output. Comprehensive analyses of physical output of fossil fuels suggest that China’s total oil production will likely reach its peak, at about 230 Mt/year (or 9.6 EJ/year), in 2018; its total gas production will peak at around 350 Bcm/year (or 13.6 EJ/year) in 2040, while coal production will peak at about 4400 Mt/year (or 91.9 EJ/year) around 2020 or so. In terms of the forecast production of these fuels, there are significant differences among current studies. These differences can be mainly explained by different ultimately recoverable resources assumptions, the nature of the models used, and differences in the historical production data. Due to the future constraints on fossil fuels production, a large gap is projected to grow between domestic supply and demand, which will need to be met by increasing imports. Net energy analyses show that both coal and oil and gas production show a steady declining trend of EROI (energy return on investment) due to the depletion of shallow-buried coal resources and conventional oil and gas resources, which is generally consistent with the approaching peaks of physical production of fossil fuels. The peaks of fossil fuels production, coupled with the decline in EROI ratios, are likely to challenge the sustainable development of Chinese society unless new abundant energy resources with high EROI values can be found.

Abstract Low oil prices under the influence of economic structure transformation and slow economic growth have hit the existing markets of traditional big oil suppliers and upgraded the conflict of oil production capacity and interest between OPEC producers and other big oil supplier countries such as the USA and Russia. Forecasting global oil production is significant for all countries for energy strategy planning, although many past forecasts have later been proved to be very seriously incorrect. In this paper, the original generalized Weng model is expanded to a multi-cycle generalized Weng model to better reflect the multi-cycle phenomena caused by political, economic and technological factors. This is used to forecast global oil production based on parameter selection from a large sample, depletion rate of remaining resources, constraints on oil reserves and cycle number determination. This research suggests that the world will reach its peak oil production in 2022, at about 4340 × 106 tonnes. China needs to plan for oil import diversity, a domestic oil production structure based on the supply pattern of large oil suppliers worldwide and the oil demand for China’s own development.

Prior studies have suggested intraaortic balloon pump (IABP) have a neutral effect on acute myocardial infarction (AMI) patients with cardiogenic shock (CS). However, the effects of IABP on patients with severe CS remain unclear. We therefore investigated the benefits of IABP in AMI patients with severe CS undergoing coronary revascularization.This study identified 14,088 adult patients with AMI and severe CS undergoing coronary revascularization from Taiwan's National Health Insurance Research Database between January 1, 1997 and December 31, 2011, dividing them into the IABP group (n = 7044) and the Nonusers group (n = 7044) after propensity score matching to equalize confounding variables. The primary outcomes included myocardial infarction(MI), cerebrovascular accidents or cardiovascular death. In-hospital events including dialysis, stroke, pneumonia and sepsis were secondary outcomes. Primary outcomes were worse in the IABP group than in the Nonusers group in 1 month (Hazard ratio (HR) = 1.97, 95% confidence interval (CI) = 1.84-2.12). The MI rate was higher in the IABP group (HR = 1.44, 95% CI = 1.16-1.79), and the cardiovascular death was much higher in the IABP group (HR = 2.07, 95% CI = 1.92-2.23). The IABP users had lower incidence of dialysis (8.5% and 9.5%, P = 0.04), stroke (2.6% and 3.8%, P

Clopidogrel is a prodrug that undergoes in vivo bioactivation to show its antiplatelet effects. Recent studies have shown that cytochrome P450 (CYP), ATP-binding cassette transporters (ABCB1), and paraoxonase-1 (PON1) play crucial roles in clopidogrel bioactivation. Here, we aim to determine the effects of genetic polymorphisms of CYP (CYP 2C19*2, CYP 2C19*3, and CYP 2C19*17), ABCB1 (ABCB1 3435C>T, ABCB1 129T>C, and ABCB1 2677G>T/A), and PON1 (PON1 Q192R, PON1 L55M, and PON1 108C>T) on the development of stent thrombosis (ST) in patients receiving clopidogrel after percutaneous coronary intervention (PCI).We evaluated the incidence of ST (0.64%) in 4964 patients who were recruited in the CAPTAIN registry (Cardiovascular Atherosclerosis and Percutaneous TrAnsluminal INterventions). The presence of genetic polymorphisms was assessed in 20 subjects who developed ST after aspirin and clopidogrel therapy and in 40 age- and sex-matched control subjects who did not develop ST, which was documented after 9 months of angiographic follow-up. ST was acute in 5 subjects, subacute in 7, late in 7, and very late in 1. The presence of CYP 2C19*2 allele was significantly associated with ST (adjusted odds ratio [ORadj]: 4.20, 95% confidence interval [CI], 1.263-9.544; P = 0.031). However, genetic variations in PON1 and ABCB1 showed no significant association with ST.We conclude that in a Taiwanese population, PON1 Q192R genotype is not associated with ST development after PCI. However, the presence of CYP 2C19*2 allele is a risk factor for ST development after PCI.

In this study, novel adaptive fuzzy fault-tolerant control method is proposed for multiple high-speed trains (HSTs) in the presence of actuator faults, unknown non-linear dynamics and external disturbances. The fuzzy logic system is used to approximate the unknown functions. Based on proportional and integral-based sliding mode technique, two adaptive fuzzy control schemes are then proposed to achieve string stability. In the first scheme, the actuator faults are not considered. In the second scheme, a novel fuzzy fault-tolerant control with fewer adjustable parameters is constructed to further reduce the online computational load. By using Lyapunov analysis, the individual stability and string stability of whole multiple HSTs are proven. In addition, all signals of the closed-loop system are uniformly ultimately bounded and all HSTs track the reference trajectory to a small compact set around zero. Finally, comparative simulation is introduced to verify the reliability and effectiveness. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The purpose of this study was to evaluate the clinical value of transvaginal elastography (TVES) combined with high-resolution transvaginal ultrasound (TVS) in the detection of parametrial invasion in cervical cancer and to compare the diagnostic performance with magnetic resonance imaging (MRI). MATERIALS AND METHODS: 52 women with histologically confirmed cervical cancer over a 2-year period were staged using International Federation of Gynecology and Obstetrics (FIGO) criteria and underwent MRI and TVES combined with TVS according to a standardized protocol before treatment. When assessing parametrial involvement with TVS, MRI, and combination of TVES and TVS, the findings were recorded and compared with histopathological results after surgery in early-stage disease (stage⩽IIa). Sensitivity, specificity accuracy, positive predictive value (PPV) and negative predictive value (NPV) were calculated for each method independently; subsequently, a matched-sample analysis was performed by using McNemar's test or chi-square test. RESULTS: Of 52 patients, 39 were early-stage disease (stage⩽IIa), and 13 were advanced-stage disease (stage⩽IIb) according to conventional FIGO staging. For the detection of parametrial infiltration, both the diagnostic sensitivity of MRI and the combination of TVS and TVES were statistically higher than alone TVS in early-stage of cervical cancer (P = 0.03 < 0.05). Both MRI and the combination of TVS and TVES had a sensitivity of 72.73%; specificity rates of 82.14% for MRI and 78.57% for the combination of TVES and TVS; and the diagnostic accuracy rates of 79.49% for MRI and 76.92% for the combination of TVES and TVS. A matched sample analysis revealed no statistically significant difference between the diagnostic performance of MRI and the combination of TVES and TVS in the assessment of parametrial invasion (all P values > 0.05). CONCLUSION: TVES combined with TVS performed by a dedicated gynecologic radiologist should be considered a promising and economic method for pre-operative work-up for cervical cancer. [ABSTRACT FROM AUTHOR]

This study investigates the case of simultaneous input and output quantisation for a class of non-linear output feedback systems subject to uncertain non-linear dynamics and non-zero initial states. An adaptive quantised observer-based output feedback controller is designed to guarantee bounded stability and H∞ performance despite input and output quantisation. In comparison with the existing work, the main contributions of this study are that: (i) an important lemma is proposed to remove the matrix equality constraint used in many existing results, and three new design methods in strict terms of linear matrix inequality techniques are proposed; (ii) this study focuses on eliminating the impact of both input and output quantisation errors. Since the impact of input and output quantisation errors cannot be fully eliminated, the estimation error is proved to be ultimately bounded and to converge to a residual set; and (iii) an adaptive compensation term is constructed to compensate for the time-variant effects caused by non-linear dynamics and uncertain parameter vectors. Finally, two numerical examples are given to show the efficacy and advantages of the proposed methods. [ABSTRACT FROM AUTHOR]

By the insertion of a limited communication network in the feedback control loop, this paper investigates the quantized H∞ control problem for discrete-time systems with random packet losses. A new quantized random packet-loss model is proposed and exploited to study the relationship among the packet-loss rate, the upper bound of consecutive packet losses, the quantizer range and the systemperformance. A convex optimizationmethod is proposed to optimize static quantzier ranges, and further an observer-based H∞ control strategy with minimized static quantizer range is proposed to guarantee the closed-loop system exponentially mean-square stable and with a prescribed H∞ disturbance attenuation level. A numerical example is given to illustrate the effectiveness and the significance of the proposed control method. [ABSTRACT FROM AUTHOR]

Abstract-In this brief, we propose a control allocation method for a particular class of uncertain over-actuated affine nonlinear systems, with unstable internal dynamics. Dynamic inversion technique is used for the commanded output to track a smooth output reference trajectory. The corresponding controlallocation law has to guarantee the boundedness of the states, including the internal dynamics, and satisfy control constraints. The proposed method is based on a Lyapunov design approach with finite-time convergence to a given invariant set. The derived control allocation is in the form of a dynamic update law which, together with a sliding mode control law, guarantees boundedness of the output tracking error as well as of the internal dynamics. The effectiveness of the control law is tested on a numerical model of the non-minimum phase planar vertical take-off and landing (P VIOL) system. [ABSTRACT FROM AUTHOR]

Weather radar plays a key role in natural disaster mitigation just as surveillance radar does in detecting objects that threaten homeland security. Both together comprise an instrumental part of radar observation. Therefore, quality control of the data gathered through radar detection is extremely important. However, radar waves propagate in the atmosphere, and an anomalous echo can occur if there are significant discontinuities in temperature and humidity in the lower boundary layer. The refractive curvature of the earth makes some errors in observation inevitable. On the night of July 3, 2003, Next Generation Radar (NEXRAD) weather radar detected an abnormal echo. The Weather Research and Forecast (WRF) model was utilized to simulate the atmospheric conditions. Radar propagation was simulated using the Advanced Refractivity Engineering Prediction System (AREPS) as well as the GIS. The results show the feasibility of establishing an abnormal propagation early-warning system and extending the application of the GIS in serving as the foundation of a Common Operation Picture (COP). Furthermore, the parameters of the boundary layer near the sea's surface in the numerical weather forecasting model need remodification. [ABSTRACT FROM AUTHOR]

This paper presents a solution to a reliable filtering problem with error variance specifications for both continuousand discrete-time systems. The filtering error variance in the sensor failure cases is guaranteed to be less than a given upper bound while the performance in the nominal case is optimized. A convergent iterative algorithm based on linear matrix inequality (LMI) is given to obtain the solution. The algorithm solves the problem without introducing additional conservativeness, and it is shown to get better performance and be less conservative compared with traditional LMI approaches. A numerical example is given to show the advantages of our approach over existing techniques. [ABSTRACT FROM AUTHOR]

Focuses on the nonfragile H[sub infinity] controller design problem for linear time-invariant systems. Assumption of the controller design to have norm-bounded uncertainties; Design methods for dynamic output feedback; Quadratic stability of the closed-loop system.

Presents an actuator fault estimation scheme based on the augmented error method for flight control system. Design of the flight control system of an F4-fighter aircraft; Details on the mathematical framework needed for optimizing the autopilot design; Effort to combine the use of robust control and fault detection and isolation techniques for fault-tolerant flight control.