Continuous System Research Articles

Vascular Reactivity Index as an Effective Predictor of Mortality in Patients With Septic Shock: A Retrospective Study.

Sepsis is a serious complication that occurs after trauma, burns, and infections, and it is an important cause of death in intensive care unit (ICU) patients. Despite many new measures being proposed for sepsis treatment, its mortality rate remains high; sepsis has become a serious threat to human health, and there is an urgent need to carry out in-depth clinical research related to sepsis. In recent years, it has been found that septic shock-induced vasoplegia is a result of vascular hyporesponsiveness to vasopressors. Therefore, this study intended to establish an objective formula related to vasoplegia that can be used to assess the prognosis of patients and guide clinical treatment. A retrospective cohort study was conducted using data from 106 septic shock patients admitted to the ICU of Jining No. 1 People's Hospital from January 2020 to December 2022. The patients were divided into mortality and survival groups based on 28-day survival, and hemodynamics were monitored by the pulse index continuous cardiac output system. The dose and duration of vasopressors, major hemodynamic parameters, lactic acid (Lac) levels, and Sequential Organ Failure Assessment scores were recorded within 48 h of hospital admission. Multifactorial logistic regression was used to analyze the independent risk factors affecting the prognosis of patients, and the predictive value of the vascular response index (VRI) was analyzed by the receiver operating characteristic (ROC) curve. The differences between the survival and mortality groups in terms of age, sex ratio, body weight, ICU length of stay, distribution of infection sites, underlying disease conditions, baseline Lac levels, and some hemodynamic parameters were not statistically significant (P > .05). The results of multifactorial logistic regression showed that the admission Acute Physiology and Chronic Health Evaluation II score, Lac level at 24 h of treatment, maximal vasoactive inotropic score at 24 h (VISmax24), maximal vasoactive inotropic score at 48 h (VISmax48), and VRI were independent risk factors affecting 28-day mortality. Within 48 h of receiving vasopressor therapy, the VRI was lower in the mortality group than in the survival group. The area under the ROC curve for the VRI was 0.86, and the best cutoff value of the VRI for predicting 28-day mortality was 32.50 (YI = 0.80), with a sensitivity of 0.90, a specificity of 0.90, and a better prediction of mortality than the other indicators. The VRI is a good predictor of mortality in patients with septic shock, and a lower VRI indicates more severe vasoplegia, poorer prognosis, and higher mortality in patients with septic shock.

The subadditivity of quantum entropy in Gaussian quantum systems

The entropy of a quantum state measures information or uncertainty contained in the quantum system and plays a crucial role in quantum information theory. Many entropic properties, such as the subadditivity, have been studied for the discrete system with a finite-dimensional state space, while much less is explored in the infinite-dimensional system. In this work, we study the entropic properties of the continuous system that models a collection of Gaussian modes or fields. In particular, we identify the parameter range for the Rényi, Tsallis, and Unified entropies of Gaussian states that they are additive, subadditive, and strong subadditive. We show that the Rényi entropies are subadditive, further giving rise to the subadditivity of the Tsallis and Unified entropies in certain parameter range. We also find that the Tsallis and Unified entropies are not strong subadditive, while the Rényi entropies with the order ranging from 1 to 2 are conjectured to admit the strong subadditivity. Our results are useful in studying quantum correlations and channel capacities in Gaussian systems.

Influence of °Brix/Acid, and flow rate of pineapple juice and electric field strength on the performance of continuous ohmic heating system.

The online version contains supplementary material available at 10.1007/s13197-024-05961-x.

A convergent finite-volume scheme for nonlocal cross-diffusion systems for multi-species populations

An implicit Euler finite-volume scheme for a nonlocal cross-diffusion system on the one-dimensional torus, arising in population dynamics, is proposed and analyzed. The kernels are assumed to be in detailed balance and satisfy a weak cross-diffusion condition. The latter condition allows for negative off-diagonal coefficients and for kernels defined by an indicator function. The scheme preserves the nonnegativity of the densities, conservation of mass, and production of the Boltzmann and Rao entropies. The key idea is to ``translate'' the entropy calculations for the continuous equations to the finite-volume scheme, in particular to design discretizations of the mobilities, which guarantee a discrete chain rule even in the presence of nonlocal terms. Based on this idea, the existence of finite-volume solutions and the convergence of the scheme are proven. As a by-product, we deduce the existence of weak solutions to the continuous cross-diffusion system. Finally, we present some numerical experiments illustrating the behavior of the solutions to the nonlocal and associated local models.

IMPROVEMENT OF DESIGN PARAMETERS OF INERTIAL TYPE FUEL CONTINUITY SYSTEMS

Multiple restart of liquid-propellant rocket engines of spacecraft in zero gravity is one of the most difficult tasks that arise in the creation of new products of rocket technology. When performing a flight task, due to the movement of the spacecraft along the passive section of the trajectory, the components of the liquid fuel are mixed with the pressurized gas in its tanks in an arbitrary manner. There is a possibility that the gas phase will be located close to the drain hole. At the time of re-turning on the propulsion engines of the spacecraft, along with fuel, gas bubbles will enter the consumable line from the tank, which can, in turn, cause a failure of their launch.
 In order to avoid this emergency, special fuel continuity systems are used. Despite the significant diversity of these systems, all of them have significant shortcomings and limited working conditions. The main purpose of using fuel continuity systems of any type is to prevent the penetration of boost gas from the tank cavity into the flow line until the tank is completely emptied.
 The paper is devoted to the analysis of the possibilities of improving the design parameters of the two most common systems for ensuring fuel continuity by creating a combined "hybrid" system on their basis. Inertial and mesh systems for ensuring fuel continuity are considered. Theoretically, an analysis of the possibility of reducing the effect of pre-start acceleration for an inertial system for ensuring fuel continuity due to the use of a mesh phase separator in the fuel supply system is carried out. The paper considers the main design parameters of this combined system, which directly affect the level of its technical perfection, as well as the possibilities of their optimization.
 The results of the work can be useful in engineering practice in the creation of new promising products of rocket and space technology.

From liver to hormones: The endocrine consequences of cirrhosis.

Hepatocrinology explores the intricate relationship between liver function and the endocrine system. Chronic liver diseases such as liver cirrhosis can cause endocrine disorders due to toxin accumulation and protein synthesis disruption. Despite its importance, assessing endocrine issues in cirrhotic patients is frequently neglected. This article provides a comprehensive review of the epidemiology, pathophysiology, diagnosis, and treatment of endocrine disturbances in liver cirrhosis. The review was conducted using the PubMed/Medline, EMBASE, and Scielo databases, encompassing 172 articles. Liver cirrhosis is associated with endocrine disturbances, including diabetes, hypoglycemia, sarcopenia, thyroid dysfunction, hypogonadotropic hypogonadism, bone disease, adrenal insufficiency, growth hormone dysfunction, and secondary hyperaldosteronism. The optimal tools for diagnosing diabetes and detecting hypoglycemia are the oral glucose tolerance test and continuous glucose monitoring system, respectively. Sarcopenia can be assessed through imaging and functional tests, while other endocrine disorders are evaluated using hormonal assays and imaging studies. Treatment options include metformin, glucagon-like peptide-1 analogs, sodium-glucose co-transporter-2 inhibitors, and insulin, which are effective and safe for diabetes control. Established standards are followed for managing hypoglycemia, and hormone replacement therapy is often necessary for other endocrine dysfunctions. Liver transplantation can address some of these problems.

New Insights on Bidirectional Associative Memory Neural Networks with Leakage Delay Components and Time-Varying Delays Using Sampled-Data Control

The sampling data control of bidirectional associative memory (BAM) neural network with leakage delay is considered in this article. The BAM model is viewed as a mixed delay that combines a distributed delay, a discrete delay that varies over time, and a delay in the leaking period. The sampling system is then converted to a continuous time-delay system using an input delay method. In order to get adequate conditions in the form of linear matrix inequalities(LMIs), we build a new Lyapunov-Krasovskii Functional (LKF) in conjunction with the free weight matrix approach. Finally, a simulation results are given to show the efficiency of the theoretical approach.

Achieving advanced nitrogen removal from mature landfill leachate in continuous flow system involving partial nitrification-anammox and denitrification

Considering the challenges associated with nitrogen removal from mature landfill leachate, a novel combined continuous-flow process integrating denitrification and partial nitrification-Anammox (PN/A) was developed using an internal circulation (IC) system and a biological aerated filter (BAF) biofilm reactor (IBBR). In this study, IBBR successfully operated for 343 days, and when influent NH4+-N concentration of mature landfill leachate reached 1258.1 mg/L, an impressive total nitrogen removal efficiency (TNRE) of 93.3 % was achieved, along with a nitrogen removal rate (NRR) of 1.13 kg N/(m3·d). The analysis of the microbial community revealed that Candidatus Kuenenia, the dominant genus responsible for anammox, accounted for 1.7 % (day 265). Additionally, Nitrosomonas, Thauera and Truepera were identified as key contributors to the efficient removal of nitrogen from mature landfill. As a novel nitrogen removal strategy, the practical application of the IBBR system offers novel perspectives on addressing mature landfill leachate.

Continuous ambulatory epilepsy detection system incorporating feature engineering

Epilepsy is a prevailing disease that affects people from different age brackets and demographic backgrounds. It leads to uncontrollable onset of seizures and can result in severe neurological injuries. In this paper, we devised a novel seizure prediction system as a real-time early warning system for patients. By using real-time transmissible, portable, and wireless devices, we can acquire raw data from scalp electroencephalogram (EEG) without any pre-processing for the input. After pre-processing, the data is fed into selected prediction algorithms based on literature review and a combination of methodologies. After times of iteration, our result shows a promising performance, with an accuracy rate of 100% Bonn dataset. We further designed a hardware data acquisition apparatus (with our program built-in) to smooth and ameliorate the data acquisition process when eliminating overmuch electrodes, which may serve as a promising seizure onset detecting device in the new era.

Deep learning-based photoplethysmography biometric authentication for continuous user verification

Biometric authentication methods have gained prominence as secure and convenient alternatives to traditional passwords and PINs. In this paper, we propose a novel approach for biometric authentication using photoplethysmography (PPG) signals and deep learning techniques. PPG is a non-invasive method that measures variations in blood volume within microvascular tissue beds, and it is typically used for monitoring heart rate and oxygen saturation. Our research leverages the unique characteristics of PPG signals to develop a robust and continuous user verification system. The primary goal of our study is to explore the feasibility and effectiveness of PPG-based biometric authentication, enabling a seamless and secure means of confirming the identity of individuals. We use a diverse dataset of PPG signals from various individuals, ensuring that it encompasses differences in skin tone, age, and other variables that can influence PPG signal characteristics. The collected data undergoes careful preprocessing, including noise removal, baseline correction, and heartbeat segmentation. For the core of our authentication system, we design and train a multiscale feature fusion deep learning (MFFD) model. This model, utilizing a Convolutional Neural Network (CNN) architecture, takes as input the relevant features extracted from PPG signals and learns to differentiate between individuals based on their unique PPG patterns. In this study, the input is constructed by gradually incorporating various features, beginning with a single PPG signal. In this study, the CNN model was trained independently, followed by the implementation of score fusion techniques. Our evaluation demonstrates the effectiveness of the PPG-based biometric authentication system, achieving high accuracy while addressing key security concerns. We consider false acceptance rate (FAR) and false rejection rate (FRR) to assess the system's performance. The model achieves the Accuracy of 99.5 % on BIDMC, 98.6 % on MIMIC, 99.2 % on CapnoBase dataset.

Optimizing integration of community-based management of possible serious bacterial infection (PSBI) in young infants into primary healthcare systems in Ethiopia and Kenya: successes and challenges

BackgroundEthiopia and Kenya have adopted the community-based integrated community case management (iCCM) of common childhood illnesses and newborn care strategy to improve access to treatment of infections in newborns and young infants since 2012 and 2018, respectively. However, the iCCM strategy implementation has not been fully integrated into the health system in both countries. This paper describes the extent of integration of iCCM program at the district/county health system level, related barriers to optimal integration and implementation of strategies.MethodsFrom November 2020 to August 2021, Ethiopia and Kenya implemented the community-based treatment of possible serious bacterial infection (PSBI) when referral to a higher facility is not possible using embedded implementation research (eIR) to mitigate the impact of COVID-19 on the delivery of this life-saving intervention. Both projects conducted mixed methods research from April-May 2021 to identify barriers and facilitators and inform strategies and summative evaluations from June-July 2022 to monitor the effectiveness of implementation outcomes including integration of strategies.ResultsStrategies identified as needed for successful implementation and sustainability of the management of PSBI integrated at the primary care level included continued coaching and support systems for frontline health workers, technical oversight from the district/county health system, and ensuring adequate supply of commodities. As a result, support and technical oversight capacity and collaborative learning were strengthened between primary care facilities and community health workers, resulting in improved bidirectional linkages. Improvement of PSBI treatment was seen with over 85% and 81% of estimated sick young infants identified and treated in Ethiopia and Kenya, respectively. However, perceived low quality of service, lack of community trust, and shortage of supplies remained barriers impeding optimal PSBI services access and delivery.ConclusionPragmatic eIR identified shared and unique contextual challenges between and across the two countries which informed the design and implementation of strategies to optimize the integration of PSBI management into the health system during the COVID-19 pandemic. The eIR participatory design also strengthened ownership to operationalize the implementation of identified strategies needed to improve the health system’s capacity for PSBI treatment.

Knotted toroidal sets, attractors and incompressible surfaces

In this paper we give a complete characterization of those knotted toroidal sets that can be realized as attractors for discrete or continuous dynamical systems globally defined in R3\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\mathbb {R}}^3$$\\end{document}. We also see that the techniques used to solve this problem can be used to give sufficient conditions to ensure that a wide class of subcompacta of R3\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\mathbb {R}}^3$$\\end{document} that are attractors for homeomorphisms must also be attractors for flows. In addition we study certain attractor-repeller decompositions of S3\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\mathbb {S}}^3$$\\end{document} which arise naturally when considering toroidal sets.

Full life cycle emission reduction potential of ultra-low emission transformation in China's cement industry

China accounts for more than 50% of the global total cement production, the emission of pollutants in the cement industry occupies a large proportion of the industries. Some provinces have first carried out in-depth treatment of the cement industry, and the national level will also introduce an implementation plan for ultra-low emission transformation of the cement industry to promote continuous improvement of China's air quality. In this work, a pollutant emission inventory covering the full life cycle of the cement industry, including organized emission, unorganized emission and transportation, was established based on pollutant discharge permit, Continuous Emission Monitoring System (CEMS) database and field investigation. And, the emission reduction potential of particulate matter (PM), sulfur dioxide (SO2) and nitrogen oxide (NOx) after the implementation of ultra-low emission transformation in cement industry was evaluated. The results show that the existing dedusting, desulphurization and denitration technologies can control the concentrations of PM, SO2 and NOx below 10 mg/m3, 35 mg/m3 and 50 mg/m3, respectively. The emission reduction potential of PM, SO2 and NOx in cement industry is 259.54 kt, 14.98 kt and 607.04 kt, corresponding emission reduction ratio is 37%, 24% and 64%, respectively. In addition, this work reveals the spatial characteristics of pollutant emission level and emission reduction potential of the cement industry, which is conducive to the rational layout of ultra-low emission transformation, and push forward the transformation task by area and stage.

Comprehensive Review of Energy Storage Systems Characteristics and Models for Automotive Applications

Currently, the electrification of transport networks is one of the initiatives being performed to reduce greenhouse gas emissions. Despite the rapid advancement of power electronic systems for electrified transportation systems, their integration into the AC power grid generates a variety of quality issues in the electrical distribution system. Among the possible solutions to this challenge is the inclusion of continuous storage systems, which can be located either onboard or offboard. The rapid development of energy storage devices has enabled the creation of numerous solutions that are leading to ever-increasing energy consumption efficiency, particularly when two or more of these storage systems are linked in a cascade and a hybrid mode. The various energy storage systems that can be integrated into vehicle charging systems (cars, buses, and trains) are investigated in this study, as are their electrical models and the various hybrid storage systems that are available.

An intelligent continuous bladder irrigation monitoring and control system: Development and preliminary assessment

Abstract Objectives: To design an intelligent continuous bladder irrigation monitoring and control system and preliminarily assess its sensitivity of the early warning of flushing anomalies. Methods: According to the principle of bladder irrigation, an intelligent continuous bladder irrigation monitoring and control system was designed. The Amesim fluid simulation software was used to establish a parameterized simulation model for the bladder perfusion process and simulate the dynamic changes of bladder pressure and volume under different perfusion speeds to assess the sensitivity of the early warning of flushing anomalies. Results: The intelligent system consisted of 3 parts: the monitoring part (a flushing fluid inlet flow monitoring device, a flushing fluid outlet flow monitoring device, and a flushing fluid outlet color recognition sensor), the transition part (a control motherboard), and the regulation part (an alarm device, an electric control device for flushing fluid input speed, and a squeezing device for flushing waste fluid line). The data of the parameterized simulation model for the bladder perfusion process suggested that the sensitivity of the system was acceptable. Conclusion: The intelligent bladder irrigation system can automatically detect, report, and resolve signal abnormalities, thereby achieving the closed-loop management of bladder irrigation. The intelligent system might be used in clinical settings to reduce the burdens of nurses and promote patients’ recovery.

Use of FreeStyle Libre for continuous glucose monitoring in adult horses.

To evaluate the feasibility of using the FreeStyle Libre (a continuous glucose monitoring system [CGMS]) for instantaneous continuous monitoring of interstitial glucose in adult horses and examine the applicability and accuracy of this system in horses submitted to combined glucose-insulin test (CGIT). Laboratory measurements and continuous glucose monitoring system (CGMS) readings were analyzed using a 2 × 2 factorial statistical model with repeated measures over time. This analysis assessed the effects of the test (factor 1), group (factor 2), and their interactions (test × group, test × time, and group × time). Pearson's correlation analysis was applied to blood glucose values. Mean comparisons were conducted using the t-test, and agreement between techniques was assessed via the Bland-Altman method, with a 95% confidence interval. Field study on private horse farms in association with a veterinary school. Ten healthy stallions were assigned to one of two groups based on their body condition scores (BCS). Group 1 (G1, n= 5) consisted of nonobese horses with a BCS of 5 or 6, while Group 2 (G2, n= 5) consisted of obese horses with a BCS of 7 or higher. A CGMS sensor was attached to the dorsolateral aspect of the proximal one third of each horse's neck. Laboratory blood glucose measurements and CGMS interstitial glucose readings were compared at different time points for up to 7days after sensor fixation. Obese horses were also submitted to CGIT on Day 4. A comparative analysis of glucose measurements obtained in G1 and G2 horses using the CGMS and enzymatic methods revealed significant group×time interactions (P<0.001) and time effects (P<0.001). No interactions were detected between group (P=0.45), test (P=0.62), group and test (P=0.28), or time and test (P=0.92). In G1 and G2, tests were significantly correlated (r=0.84 and P=0.00) at all time points (T0-T5). Agreement between the glucose values obtained using different methods was excellent despite a small time delay in CGMS detection of rapid changes in blood glucose. It was concluded that the CGMS can be used for indirect assessment of glycemic status (ie, based on interstitial glucose measurements) in nonobese and obese adult horses submitted to CGIT.

Определение местоположения людей в горных выработках угольной шахты — реальность и мифы

The study considers the systems of location of workers in coalmine excavations; the application of such systems is regulated by the Safety rules in coalmines. It has been shown that in Russian coalmines, zonal-type systems and continuous systems are operated. The compliance of each type of system with the requirements of the Safety rules in terms of design, functionality, and technical parameters has been assessed. The features of building a zonal-type system as to the methodology of placing tag readers in excavations have been determined. The continuous system functionality has been analyzed. It has been shown that in addition to the main function of personnel’s location, the system acquires other useful properties, i.e., the use of gas analyzers installed in the headlamp to transmit measurements in real-time mode indicating a measurement location; the implementation of two-way voice communication between a mining dispatcher and workers in excavations via individual headlamps. By the results of the study, the concluding provisions have been formulated: in zonal-type location systems, it is possible to meet the regulatory requirement for a five-second data update period on the condition that the maximum distance between readers does not exceed 60 meters; in continuous personnel’s location systems, due to their design features, additional functions to ensure industrial safety and organizational properties are implemented, expanding the practical value of such devices.

Multi-objective continuous review inventory policy using MOPSO and TOPSIS methods

In the dynamic business environment of today, decision-making involves considering various conflicting aspects. Inventory planning problems aim to determine how much and when to order products to satisfy customer demand at the lowest possible cost while maintaining a desirable service level. These problems can be formulated as a MOPSO algorithm, which is used to handle multiple objectives in a continuous review stochastic inventory control system (r, Q). Unfortunately, most multi-objective inventory models have been solved by aggregating objectives using specific weights or by optimizing only one objective and treating the others as constraints. Considering the complexity of real-world inventory control problems, which involves conflicting objectives such as minimizing cost and maximizing service level, the need arises to employ more precise optimizers that can generate better and more diverse non-dominated solutions of reorder point and order size system. In this paper multi-criteria decision-making framework that combines MOPSO algorithm and TOPSIS method to generate a Pareto front of non-dominated solutions and rank them based on decision makers' preferences. Initially, the original MOPSO is applied to the multi-objective inventory control problem, and then the mutation operator is integrated into the MOPSO to maintain diversity in the swarm and explore the entire search space. Next, the leader selection strategy called the geographically-based system (Grids) is replaced by the crowding distance factor to choose the global optimal particle as a leader. Additionally, the ε-dominance concept is employed to limit the archive size and maintain more diversity and convergence in the MOPSO for optimizing the inventory control problem. In conclusion, this work not only pioneers a cutting-edge approach to multi objective inventory control but also underscores its practical value. By facilitating the generation of superior solutions that cater to diverse decision-maker preferences, our methodology resonates deeply with real-world challenges and sets a new benchmark for effective inventory planning.

Estimation of the Impact of Vaccination Intervention on Recovered Coronavirus Patients

This work estimated the impact of vaccination intervention on coronavirus patients who have recovered from the disease and the vulnerability index of the recovered population due to the impact of vaccine was also investigated. This work adopted a numerical solution to study the continuous dynamical system of linear first order differential equations describing a SEIR (Susceptible, Exposed, Infected, Recovered) model on the spread of Coronavirus Disease – 2019 (COVID-19). To tackle this problem, MATLAB ordinary differential equation of order 45 (ODE45) numerical method was adopted for the analysis. The vulnerability index of the recovered population was low due to the impact of vaccine meaning that the recovered population will gain immunity and they will not be re-infected. The study recommended that coronavirus patients who have recovered from the disease should ensure that they have vaccination administered to them to avoid re-occurrence of the virus attack as an intervention strategy.

Why death and aging ? All memories are imperfect

Recent papers have emphasized the primary role of cellular information management in biological and evolutionary development. In this framework, intelligent cells collectively measure environmental cues to improve informational validity to support natural cellular engineering as collaborative decision-making and problem-solving in confrontation with environmental stresses. These collective actions are crucially dependent on cell-based memories as acquired patterns of response to environmental stressors. Notably, in a cellular self-referential framework, all biological information is ambiguous. This conditional requirement imposes a previously unexplored derivative. All cellular memories are imperfect. From this atypical background, a novel theory of aging and death is proposed. Since cellular decision-making is memory-dependent and biology is a continuous natural learning system, the accumulation of previously acquired imperfect memories eventually overwhelms the flexibility cells require to react adroitly to contemporaneous stresses to support continued cellular homeorhetic balance. The result is a gradual breakdown of the critical ability to efficiently measure environmental information and effect cell-cell communication. This age-dependent accretion governs senescence, ultimately ending in death as an organism-wide failure of cellular networking. This approach to aging and death is compatible with all prior theories. Each earlier approach illuminates different pertinent cellular signatures of this ongoing, obliged, living process.