Search

Purpose The firewater deluge system (FDS) can provide water automatically through a deluge valve when a fire breaks out. However, there are many fire hazards caused by the abnormal operating state of the FDS. To monitor and predict the working state of the FDS, this paper aims to propose a firewater deluge monitoring and forecasting system using the Internet of Things (IoT) technology. Design/methodology/approach The firewater deluge monitoring and forecasting system consists of three layers: the sensing layer, network layer and application layer. The firewater pressure obtained by the monitoring nodes was transmitted to the local gateway and then to the remote monitoring center. In the application layer, an autoregressive moving average (ARMA) model was put forward to forecast the firewater pressure. Furthermore, a genetic algorithm (GA) was proposed to perfect the order determination method of the ARMA model. Finally, a Web application was developed to display the real time and predicted working status of the FDS. Findings The predicted results show that the ARMA model improved by the GA (GA-ARMA) is significantly better than traditional ARMA models in terms of mean relative error, mean absolute error and mean square error. Moreover, the proposed system is demonstrated to be effective, and an early warning can be alerted to remind users of repairing abnormal FDS equipment ahead of fire dangers. Originality/value The proposed system cannot only be applied to the FDS of all buildings to avoid fire hazards by monitoring and predicting the working state of the FDS, but can also be widely used in other fields, such as environmental monitoring, intelligent logistics and intelligent transportation.

Background Acute type A aortic dissection (AAAD) is a devastating condition with the human aortic smooth muscle cells (HASMCs) reduced proliferation and increased apoptosis. Integrin α5β1 and FAK are the important proangiogenic factors involved in regulating angiogenesis. The aim of the study was to investigate the role of integrin α5β1 and FAK in AAAD patients and the potential mechanisms. Methods The aortic tissue samples were collected from 8 AAAD patients and 4 organ donors obtained from Zhongshan Hospital of Fudan University. The level of apoptosis in the aortic tissues were assessed by immunohistochemical staining (ICH) and Terminal-deoxynucleoitidyl transferase mediated nick end labeling assay (TUNEL). The expression of integrin α5β1 and FAK were detected. Furtherly, integrin α5β1 was dificiently expressed in HASMCs and the interaction with FAK was detected by co-immunoprecipitation analysis (Co-IP). The levels of proliferation and apoptosis were assessed by cell-counting Kit-8 analyses (CCK-8) and flow cytometry after integrin α5β1 dificiently. Results The levels of integrin α5β1 and FAK were both significantly decreased in AAAD patients. Down-regulating the expression of integrin α5β1-FAK compound could remarkablely induce the increased apoptosis and decreased proliferation in HASMC, which indicated integrin α5β1-FAK might play a important role in the development of AAAD. Conclusions The down-regulaiton of integrin α5β1-FAK associates with increased apoptosis and decreased proliferation in aortic smooth muscle cells, and might be a potential therapeutic target for AAAD.

Background: The lung microbiota and host immune response is thought to be a key player in the progression of pneumonia. However, the critical features of the microbiota have rarely been studied in severe community-acquired pneumonia (SCAP) patients. This study aimed to explore the correlations among the lung microbiota and the host immune defense, the disease severity, and the outcome in SCAP patients. Methods: A prospective and observational study in the intensive care unit (ICU) of four hospitals in China was performed. The lung microbiota was quantified and characterized using metagenomic next-generation sequencing (mNGS), collecting sputum and bronchoalveolar lavage fluid (BALF) in SCAP and CAP patients. Risk factors for disease progress and prognosis were investigated by logistic regression. In addition, transcriptomics was applied to explore host immune variation and the interaction between microbiota and host immune responses. Results: Our results showed that the microbiome α- and β-diversity in SCAP patients were significantly lower than those in CAP patients and lower in nonsurvivors than survivors. The Simpson index, the existence of Streptococcus pneumonia, the delta-SOFA score, the use of immunosuppressor, and activated partial thromboplastin time (APTT) were independently associated with the 28-day mortality of SCAP patients. Furthermore, the differentially expressed genes, including Opiorphin Prepropeptide (OPRPN), Histatin 1 (HTN1), Histatin 3 (HTN3), Lipocalin 1 (LCN1), Follicular Dendritic Cell Secreted Protein (FDCSP) and Statherin (STATH) in SCAP were correlated with immune response pathways. The neutrophil proportions and degranulation were suppressed in the nonsurvivors of SCAP. At the same time, interleukin-10 signaling was activated, while interferon-α, -β, and -γ responses were suppressed in the dismal outcome patients. Conclusions: Our findings confirmed that the lung microbiota played an essential role in association with the severity of pneumonia and represented a significant contributor to heterogeneity in SCAP by altering host immune responses.

Abstract In this article, a multilabel support vector machine (SVM)-based approach is investigated to address the simultaneous decay detection of the marine propulsion system. To verify the performance of the algorithm, we perform some experiments using a simulation dataset from a real-data validated numerical simulator of a Frigate. In particular, we try to train the model without simultaneous decay data, considering the great difficulty of obtaining simultaneous decay data in practice. The experimental results show that the proposed approach can identify the complex decay modes of the marine propulsion system effectively using only simple decay data in the training process. Introduction The propulsion system is considered to be the “heart” of a marine ship (Li et al. 2019a). Its safety and reliability are critical to the regular operation of the ship (Bayer et al. 2018; Cheliotis & Lazakis, 2018; Lazakis et al. 2016). However, performance decay may occur to the propulsion system due to the high humidity and high salt characteristics of the marine environment (Fang et al. 2018; Kang et al. 2019; Wang et al. 2019). The decay modes can be divided into single decay and simultaneous decay. Single decay indicates a simple decay mode that only one kind of decay occurs at a time, and simultaneous decay indicates a complex decay mode that multiple decays occur at the same time. To improve the safety and reliability of the marine propulsion system, researchers have proposed many related approaches from the perspective of fault diagnosis.

In this study, magnetic solid acid Fe3O4/C–SO3H600 was synthesized and applied in catalytic fast pyrolysis of cellulose for the selective production of levoglucosenone (LGO). The catalytic pyrolysis of cellulose could not only reduce the reaction-required temperature and promote the LGO production, but also could be reused for recycling in an economical and practical approach. Under the experimental conditions that the ratio of catalyst to cellulose was 1:1 and the pyrolysis temperature was 300 °C, the yield of LGO reached 20 wt%. This research also explored the mechanism of cellulosic pyrolysis to produce LGO, indicating that LGO could be produced via further dehydration of levoglucosan.

Fermentable sugars are a group of pivotal intermediates and platform compounds achieved by the conversion of lignocellulose. Fast pyrolysis, as a little-explored way to liberate levoglucosan from biomass, may have a potential capability to overcome the technical barriers and fundamental limitations for efficient saccharification. Pretreatment prior to fast pyrolysis is essential to improve levoglucosan yield from lignocellulose. Contrary to typical high-temperature acid pretreatments, a pretreatment under mild conditions was evaluated and optimized, where different acid (formic acid, acetic acid, oxalic acid, nitric acid, phosphoric acid, sulphuric acid and hydrochloric acid) were employed at room temperature prior to fast pyrolysis of lignocellulose. Due to the alteration of chemical compositions and physical structures of biomass, especially the elimination of alkali and alkaline earth metals, the levoglucosan yield of dilute acid pretreated biomass was improved remarkably as compared with that of raw material, meanwhile claimed that acid pretreatments at room temperature had an enough capability in efficient utilization of biomass. In sum, this study offered a novel and economical strategy for selective saccharification of lignocellulose for industrialized bio-refinery.

Halide segregation is a critical bottleneck that hampers the application of mixed-halide perovskite nanocrystals (NCs) in both electroluminescent and down-conversion red-light-emitting diodes. Herein, we report a strategy that combines precursor and surface engineering to obtain pure-red-emitting (peaked at 624 nm) NCs with a photoluminescence quantum yield of up to 92% and strongly suppresses the halide segregation of mixed-halide NCs under light irradiation. Red-light-emitting diodes (LED) using these mixed-halide NCs as phosphors exhibit color-stable emission with a negligible peak shift and spectral broadening during operation over 240 min. By contrast, a dramatic peak shift and spectral broadening were observed after 10 min of operation in LEDs based on mixed-halide NCs synthesized by a traditional method. Our strategy is critical to achieving photo- and band-gap-stable mixed-halide perovskite NCs for a variety of optoelectronic applications such as micro-LEDs.

Background Diabetes mellitus (DM) has become a common risk factor for pyogenic liver abscess (PLA) patients, Klebsiella pneumoniae is a primary pathogen of PLA (KPLA). The purpose of this study was to evaluate the clinical and microbiological characteristics in PLA patients with or without DM induced by Klebsiella pneumoniae or not.Methods The clinical data of the total 557 PLA patients were collected in Zhongshan Hospital from January 2015 to December 2020. The liver abscess were confirmed using abdominal ultrasound (US)，computerized tomography (CT), and/or magnetic resonance imaging (MRI). The 557 patients were divided into two groups, PLA with DM and PLA without DM. In the group of PLA with DM, the patients were further separated into KPLA with DM and non-KPLA with DM.Results The total of 557 patients with PLA were analyzed, 225 (40.40%) patients comorbided DM. Among PLA patients with DM, there is a higher proportion of patients with hypertension (42.22%) and fatty liver diseases (38.67%), the most common clinical manifestation is frail and fatigue (18.22%), and more likely to progress to sepsis and metastatic infections such as periorbital infection. The PLA patients with DM have higher inflammatory markers (WBC, N%, CRP, ESR and PCT). There was significant difference between the group of PLA with DM and PLA without DM in the percentage of neutrophils, liver enzymes, albumin, glucose metabolism (blood glucose, glycated hemoglobin and glycated albumin), lipid metabolism (triglycerides, low density lipoprotein, high density lipoprotein), blood sodium and chlorine, blood urea nitrogen and higher heart markers ( proBNP and CK-MB). In KPLA patients with DM compared with non-KPLA with DM, inflammatory markers (WBC, N%, CRP, ESR and PCT), liver function index (TB, CB, ALT, AST, ALP and r-GT) and cardiac markers (cTnT and proBNP) are more higher. The level of albumin, serum sodium and ferritin are more lower between the KPLA patients with DM and non-KPLA with DM. Detection of liver abscess by high-throughput sequencing is more sensitive and accurate. There was no in-hospital mortality.Conclusions The study found that in the PLA patients with diabetic DM, Klebsiella pneumoniae infection is the most common, which is more prone to organ dysfunction and electrolyte disorder. High-throughput sequencing can help early diagnosis and accurate treatment of PLA patients.

The time-symmetric formalism endows the weak measurement and its outcome, the weak value,many unique features. In particular, it allows a direct tomography of quantum states without resort to complicated reconstruction algorithms and provides an operational meaning to wave functions and density matrices. Here, we propose and experimentally demonstrate the direct tomography of a measurement apparatus by taking the backward direction of weak measurement formalism. Our protocol works rigorously with the arbitrary measurement strength, which offers an improved accuracy and precision. The precision can be further improved by taking into account the completeness condition of the measurement operators, which also ensures the feasibility of our protocol for the characterization of the arbitrary quantum measurement. Our work provides new insight on the symmetry between quantum states and measurements, as well as an efficient method to characterize a measurement apparatus., 6 pages, 3 figures

Lignin-carbohydrate complex (LCC) is the native existing form of major components in lignocellulose. In this study, the structural cross-link between lignin and polysaccharides in lignocellulose was quantitatively estimated with carboxymethylation-separation (CM-Sep) method, and its influence on lignocellulose pyrolysis was systematically investigated. The cross-linked lignin was found to positively correlate with the production of small molecules and furan derivatives while negatively affecting the generation of anhydrous sugars. Content of small molecules was increased by 97% while that of anhydrous sugars was decreased by 47% in pyrolytic products with levoglucosan yield lowered by 54 wt% in the existence of cross-linked lignin. Furthermore, the impact of cross-linked lignin was revealed to be significantly distinguished from free lignin. Impeded glycosidic end formation and boosted glycosyl ring scission as well as lignin fragmentation were responsible for the distinction. Excellent correlations between structural cross-link and lignocellulose pyrolytome could facilitate product prediction and process design.

Quantum target detection is an emerging application that utilizes entanglement to enhance the sensing of the presence of an object. Although several experimental demonstrations for certain situations have been reported recently, the single-shot detection limit imposed by the Helstrom limit has not been reached because of the unknown optimum measurements. Here we report an experimental demonstration of quantum target detection, also known as quantum illumination, in the single-photon limit. In our experiment, one photon of the maximally entangled photon pair is employed as the probe signal and the corresponding optimum measurement is implemented at the receiver. We explore the detection problem in different regions of the parameter space and verify that the quantum advantage exists even in a forbidden region of the conventional illumination, where all classical schemes become useless. Our results indicate that quantum illumination breaks the classical limit for up to 40%, while approaching the quantum limit imposed by the Helstrom limit. These results not only demonstrate the advantage of quantum illumination, but also manifest its valuable potential of target detection.

Aiming at dealing with the difficulty for traditional emergency rescue vehicle (ECV) to enter into limited rescue scenes, the electro-hydraulic steer-by-wire (SBW) system is introduced to achieve the multi-mode steering of the ECV. The overall structure and mathematical model of the SBW system are described at length. The fractional order proportional-integral-derivative (FOPID) controller based on fractional calculus theory is designed to control the steering cylinder’s movement in SBW system. The anti-windup problem is considered in the FOPID controller design to reduce the bad influence of saturation. Five parameters of the FOPID controller are optimized using the genetic algorithm by maximizing the fitness function which involves integral of time by absolute value error (ITAE), peak overshoot, as well as settling time. The time-domain simulations are implemented to identify the performance of the raised FOPID controller. The simulation results indicate the presented FOPID controller possesses more effective control properties than classical proportional-integral-derivative (PID) controller on the part of transient response, tracking capability and robustness.

For the sake of realizing dynamic switch among three steering modes for the four wheel independent steering (4WIS) rescue vehicle in the non-stop state, the switch control strategy and the optimized wheel switch trajectory are studied in this paper. Aiming at ensuring the constant turning radius of the 4WIS rescue vehicle in the switch process of steering modes, the steering angle relationships between the driving wheel and driven wheels are derived, and the desired driving wheel angle of the target steering mode is calculated. The B-spline curve is proposed to design the switch trajectory of the driving wheel. Two objectives including minimizing the sudden change of vehicle dynamic parameters and minimizing the energy consumption in the switch process are discussed. A multi-objective genetic algorithm (MOGA) based on non-dominated sorting genetic algorithm II (NSGA-II) is proposed to deal with the optimization problem of the wheel switch trajectory. The numerical simulations based on Matlab/Simulink indicate that the presented algorithm can generate the Pareto optimal solutions and is suitable for the optimization of the wheel switch trajectory. In addition, the proposed switch control strategy of steering modes for the 4WIS rescue vehicle in the non-stop state is validated to be reasonable and effective.

To improve the road feeling of the steer-by-wire (SBW) system, a fractional order PID (proportion-integral-derivative) method with a fault tolerant module is proposed in this paper. Firstly, the overall road feeling control strategy of the SBW system is introduced, and then the mathematical model of road feeling control is established. Secondly, a fractional order PID (FOPID) controller is designed to control torque of the road feeling motor. Furthermore, genetic algorithm (GA) is applied to tune the FOPID controller’s parameters. Thirdly, a fault tolerant module aiming at potential failures of the motor’s torque sensor is studied to improve the reliability of the system. Kalman Filter (KF) algorithm is utilized in the fault tolerant module so as to detect failures of the motor’s torque sensor, and then fault tolerant module reconfigures the motor’s torque estimated by KF as a substitute when the torque sensor fails. Finally, simulations based on MATLAB are performed with the proposed control strategy to identify its performance, and the results demonstrate that the proposed control method is feasible and accurate.

Sepsis is a life-threatening illness with a challenging diagnosis. Rapid detection is the key to successful treatment of sepsis. To investigate diagnostic value, the plasma protein profiles of inflammatory biomarkers, cytokines, and endothelial functional markers were compared between healthy controls, SIRS, and septic patients.The plasma protein profiles were performed by Luminex Assay in a cohort of 50 SIRS patients, 82 septic patients and 25 healthy controls. Fourteen plasma proteins were analyzed in the same cohort: IL-1β, IL-6, IL-8, IL-10, CCL-2, VEGF, VEGF-C, VEGFR2, CD62E, CD62P, MFG-E8, ICAM-1, TFPI, Urokinase.IL-2R, IL-6, IL-8, IL-10, CCL-2, ICAM-1, and Urokinase were significantly higher in sepsis patients than SIRS patients. VEGF, IL-1β, CD62E, CD62P, MFG-E8, and TFPI have no statistical difference. VEGF-C, VEGFR2 were significantly different in SIRS patients than sepsis patients. Urokinase, ICAM-1, and VEGFR2 were significantly different between sepsis group and SIRS group. The AUCs of Urokinase, ICAM-1, and VEGFR2 and the combination for the diagnosis of sepsis were 0.650, 0.688, 0.643, and 0.741, respectively.Most patients have the higher level of several cytokines and developed endothelial cell injury in the initial phase of sepsis, Urokinase, ICAM-1, and VEGFR2 may be useful to evaluate severity and prognosis of sepsis patients.

Quantum coherence is a fundamental resource that quantum technologies exploit to achieve performance beyond that of classical devices. A necessary prerequisite to achieve this advantage is the ability of measurement devices to detect coherence from the measurement statistics. Based on a recently developed resource theory of quantum operations, here we quantify experimentally the ability of a typical quantum-optical detector, the weak-field homodyne detector, to detect coherence. We derive an improved algorithm for quantum detector tomography and apply it to reconstruct the positive-operator-valued measures of the detector in different configurations. The reconstructed positive-operator-valued measures are then employed to evaluate how well the detector can detect coherence using two computable measures. As the first experimental investigation of quantum measurements from a resource theoretical perspective, our work sheds new light on the rigorous evaluation of the performance of a quantum measurement apparatus.

Hollow-core fiber (HCF) promises to unify air-borne light propagation and non-line-of-sight transmission, thus holding great potential for versatile photonics-based quantum information applications. The early version of HCF based on photonic-bandgap guidance has not proven itself a reliable quantum channel because of the poor modal purity in both spatial and polarization domains, as well as significant difficulty in fabrication when the wavelength shifts to the visible region. In this work, based on the polarization degree of freedom, we demonstrate high-fidelity ( ∼ 0.98 ) single-photon transmission and distribution of entangled photons over a 36.4 m hollow-core conjoined-tube fiber (CTF) by using commercial silicon single-photon avalanche photodiodes. Our CTF realizes the combined merits of low loss, high spatial modal purity, low polarization degradation, and low chromatic dispersion. We also demonstrate single-photon low-latency ( ∼ 99.96 % speed of light in vacuum) transmission, paving the way for extensive uses of HCF links in versatile photonics-based quantum information processing.

With wide applications in surveillance and human-robot interaction, view-invariant human action recognition is critical, however, challenging, due to the action occlusion and information loss caused by view change. Current methods mainly seek for a common feature space for different views. However, such solutions become invalid when there exist few common features, e.g. large view change. To tackle the problem, we propose an AttentioN Transfer (ANT) Network for view-invariant action recognition. Other than transferring features, ANT transfers attention from the reference view to arbitrary views, which correctly emphasize crucial body joints and their relations for view-invariant representation. In addition, the attention calculation method taking into account both recognition contribution and reliability of skeleton joints generates effective attention. Experiments showed its effectiveness for correctly locating crucial body joints in action sequences. We exhaustively evaluate our approach on the UESTC and the NTU dataset with three types of view-invariant evaluations, i.e. X-view, X-sub, and Arbitrary-view evaluation. Experiment results demonstrate its superiority in view-invariant representation and recognition.

This study aims to investigate the effects of a quadriceps isometric contraction exercise method in the treatment of knee osteoarthritis (OA).A total of 250 patients with a confirmed diagnosis of knee OA were enrolled. The patients were randomly divided into an exercise treatment test group (128 patients) and a traditional treatment control group (122 patients). Quadriceps isometric contraction exercise was used in the test group, and local physiotherapy and oral nonsteroidal anti-inflammatory drugs were used in the control group. Knee joint function was evaluated with a visual analog scale (VAS) score and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire before treatment, and 1 and 3 months after treatment.VAS scoring and the WOMAC questionnaire showed significant relief in pain 1 month after treatment in the test group (P 0.05), but minimal relief in the control group; at 1 month, there was also minimal joint function improvement in the test group (P 0.05), but significant improvement in the control group (P 0.05). However, 3 months after treatment, pain relief and knee joint function were more improved in the test group than in the control group, with a significant difference (P 0.05).Through our short-term observation, joint pain was effectively relieved and knee joint function was improved with systematic quadriceps isometric contraction exercise.

Pretreatment is a vital process for efficient saccharification and utilization of lignocellulose. In this study, crude glycerol derived from biodiesel production was used for pretreatment to facilitate selective saccharification via fast pyrolysis. Due to the efficient removal of alkali and alkaline earth metals (>95.0%) and lignin (79.4%) by crude glycerol pretreatment, the yield of levoglucosan was evaluated to 25.2% as compared to those from pure glycerol pretreated (14.4%) and untreated sugarcane bagasse (8.4%). Meanwhile, the production of inhibitors (e.g. acetic acid, phenol) to biocatalysts was also obviously inhibited from crude glycerol pretreated biomass. Consequently, this work provided a cost-effective and eco-friendly pretreatment mode, which could not only make full utilization of crude glycerol, but also improve the fermentability of lignocellulosic pyrolysate.

Considering the demand for vehicle stability control and the existence of uncertainties in the four-wheel steering (4WS) system, the mixed H2/H&infin, robust control methodology of the 4WS system is proposed. Firstly, the linear 2DOF vehicle model, the nonlinear 8DOF vehicle model, the driver model, and the rear wheel electrohydraulic system model were constructed. Secondly, based on the yaw rate tracking strategy, the mixed H2/H&infin, controller was designed with the optimized weighting functions to guarantee system performance, robustness, and the robust stability of the 4WS vehicle stability control system. The H&infin, method was applied to minimize the effects of modeling uncertainties, sensor noise, and external disturbances on the system outputs, and the H2 method was used to ensure system performance. Finally, numerical simulations based on Matlab/Simulink and hardware-in-the-loop experiments were performed with the proposed control strategy to identify its performance. The simulation and experimental results indicate that the handling stability of the 4WS vehicle is improved by the H2/H&infin, controller and that the 4WS system with the H2/H&infin, controller has better handling stability and robustness than those of the H&infin, controller and the proportional controller.

Objective:A systematic review and meta-analysis were used to directly evaluate the direct anterior approach (DAA) and the posterior approach (PA) for early efficacy and safety of total hip arthroplasty (THA).Methods:Control-led trials assessing DAA and PA for the efficacy and safety of THA were searched in the database. Articles were reviewed according to predetermined inclusion and exclusion criteria; the quality of the methodology included in a given study was strictly assessed before data extraction. Moreover, meta-analysis was performed for outcomes that can be combined; otherwise, descriptive analysis was performed.Results:There were 20 articles included, with a total of 7377 patients. Among these, 3728 and 3649 cases were in the DAA and PA groups, respectively. There was no difference between the DAA and PA groups at postoperative week 2 in the number of patients using the assistive ambulatory device or in time needed to completely discontinue all assistive ambulatory devices. Descriptive analysis found that DAA was slightly better than PA regarding early functional recovery and activity after surgery, as well as postoperative pain relief. Hospitalisation stay in the DAA group was shorter than in the PA group, in which the patients had a shorter operative time. Radiographic outcomes showed that there was little difference in prosthetic position between the DAA and PA groups. The proportions of intraoperative fractures and postoperative lateral cutaneous nerve of the thigh (LCNT) neuropraxia were significantly higher in the DAA group than in patients who underwent PA.Conclusion:Compared with PA, DAA presents superior early recovery following THA.