scholarly journals The Role of Oxygen Intake and Liver Enzyme on The Dynamics of Damaged Hepatocytes: Implications to Ischaemic Liver Injury via A Mathematical Model

2020 ◽  
Author(s):  
Aditi Ghosh ◽  
Claire Onsager ◽  
Leon Arriola ◽  
Andrew Mason ◽  
William Lee ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Liver Injury ◽  
Real Time ◽  
The Body ◽  
Model Parameters ◽  
Oxygen Intake ◽  
Serum Aminotransferase ◽  
Time Dynamics ◽  
Novel Approach ◽  
Time Basis

AbstractIschaemic Hepatitis (IH) or Hypoxic Hepatitis (HH) also known as centrilobular liver cell necrosis is an acute liver injury characterized by a rapid increase in serum aminotransferase. The liver injury typically results from another underlying medical conditions like cardiac failure, respiratory failure and septic shock in which the liver becomes damaged due to deprivation of either blood or oxygen. IH is a potentially lethal condition which is often preventable if diagnosed properly. Unfortunately, mechanism that causes IH are often not well understood, making it difficult to diagnose or accurately quantify the patterns of related biomakers. In most cases, currently the only way to determine a case of IH (i.e., to diagnose it) is to rule out all other possible conditions for other liver injuries. A better understanding of the liver’s response to IH is necessary to aid in its diagnosis, measurement and improve outcomes. The goal of this study, is to identify mechanisms that can alter a few associated biomarkers for reducing density of damaged hepatocytes, and thus reduce chances of IH. To this end, we develop a mathematical model capturing dynamics of hepatocytes in the liver through the rise and fall of associated liver enzymes aspartate transaminase (AST), alanine transaminase (ALT) and lactate dehydrogenase (LDH) related to condition of IH. The model analysis provides a novel approach to predict the level of biomarkers given variations in the systemic oxygen in the body. Using IH patient data in US, novel model parameters are described and then estimated for the first time to capture real time dynamics of hepatocytes in the presence and absence of IH condition. Different scenarios of patient conditions were also analyzed and validated using empirical information. This study and its results may allow physicians to estimate the extent of liver damage in a IH patient based on their enzyme levels and receive faster treatment on real time basis.

scholarly journals The role of oxygen intake and liver enzyme on the dynamics of damaged hepatocytes: Implications to ischaemic liver injury via a mathematical model

PLoS ONE ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. e0230833
Author(s):  
Aditi Ghosh ◽  
Claire Onsager ◽  
Andrew Mason ◽  
Leon Arriola ◽  
William Lee ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Liver Injury ◽  
Real Time ◽  
The Body ◽  
Model Parameters ◽  
Oxygen Intake ◽  
Serum Aminotransferase ◽  
Time Dynamics ◽  
Novel Approach

Ischaemic Hepatitis (IH) or Hypoxic Hepatitis (HH) also known as centrilobular liver cell necrosis is an acute liver injury characterized by a rapid increase in serum aminotransferase. The liver injury typically results from different underlying medical conditions such as cardiac failure, respiratory failure and septic shock in which the liver becomes damaged due to deprivation of either blood or oxygen. IH is a potentially lethal condition that is often preventable if diagnosed timely. The role of mechanisms that cause IH is often not well understood, making it difficult to diagnose or accurately quantify the patterns of related biomarkers. In most patients, currently, the only way to determine a case of IH is to rule out all other possible conditions for liver injuries. A better understanding of the liver’s response to IH is necessary to aid in its diagnosis, measurement, and improve outcomes. The goal of this study is to identify mechanisms that can alter associated biomarkers for reducing the density of damaged hepatocytes, and thus reduce the chances of IH. We develop a mathematical model capturing dynamics of hepatocytes in the liver through the rise and fall of associated liver enzymes aspartate transaminase (AST), alanine transaminase (ALT) and lactate dehydrogenase (LDH) related to the condition of IH. The model analysis provides a novel approach to predict the level of biomarkers given variations in the systemic oxygen in the body. Using IH patient data in the US, novel model parameters are described and then estimated for the first time to capture real-time dynamics of hepatocytes in the presence and absence of IH condition. The results may allow physicians to estimate the extent of liver damage in an IH patient based on their enzyme levels and receive faster treatment on a real-time basis.

Biorobots, Nonlinear Dynamics and Perception

2008 ◽  
Vol 58 ◽  
pp. 143-152
Author(s):  
Paolo Arena ◽  
Davide Lombardo ◽  
Luca Patanè
Keyword(s):  
Nonlinear Dynamics ◽  
Real Time ◽  
Continuous Time ◽  
Biologically Inspired ◽  
Time Dynamics ◽  
Nonlinear Network ◽  
Biologically Inspired Robots ◽  
Novel Approach ◽  
Perceptual Control ◽  
Efficient Control

In this contribution a survey on a novel approach to locomotion and perception in biologically inspired robots is presented. The basic electronic architecture for modeling and implementing nonlinear dynamics involved in motion and perceptual control of the robot is the Cellular nonlinear network paradigm. It is shown how this continuous time lattice of neural-like circuits can generate suitable and real-time dynamics for efficient control of multi-actuators moving machines, and also to create the basis for a perceptual control of their behaviors.

scholarly journals Adaptive and Personalized Plasma Insulin Concentration Estimation for Artificial Pancreas Systems

2018 ◽  
Vol 12 (3) ◽  
pp. 639-649 ◽  
Author(s):  
Iman Hajizadeh ◽  
Mudassir Rashid ◽  
Sediqeh Samadi ◽  
Jianyuan Feng ◽  
Mert Sevil ◽  
...  
Keyword(s):  
Real Time ◽  
Plasma Insulin ◽  
Artificial Pancreas ◽  
Time Estimation ◽  
The Body ◽  
Insulin Concentration ◽  
Model Parameters ◽  
Plasma Insulin Concentration ◽  
Real Time Estimation ◽  
Clinical Experiments

Background: The artificial pancreas (AP) system, a technology that automatically administers exogenous insulin in people with type 1 diabetes mellitus (T1DM) to regulate their blood glucose concentrations, necessitates the estimation of the amount of active insulin already present in the body to avoid overdosing. Method: An adaptive and personalized plasma insulin concentration (PIC) estimator is designed in this work to accurately quantify the insulin present in the bloodstream. The proposed PIC estimation approach incorporates Hovorka’s glucose-insulin model with the unscented Kalman filtering algorithm. Methods for the personalized initialization of the time-varying model parameters to individual patients for improved estimator convergence are developed. Data from 20 three-days-long closed-loop clinical experiments conducted involving subjects with T1DM are used to evaluate the proposed PIC estimation approach. Results: The proposed methods are applied to the clinical data containing significant disturbances, such as unannounced meals and exercise, and the results demonstrate the accurate real-time estimation of the PIC with the root mean square error of 7.15 and 9.25 mU/L for the optimization-based fitted parameters and partial least squares regression-based testing parameters, respectively. Conclusions: The accurate real-time estimation of PIC will benefit the AP systems by preventing overdelivery of insulin when significant insulin is present in the bloodstream.

scholarly journals The Role of Alcohol Consumption on Acetaminophen Induced Liver Injury: Implications from A Mathematical Model

2020 ◽  
Author(s):  
Aditi Ghosh ◽  
Isaac Berger ◽  
Christopher H. Remien ◽  
Anuj Mubayi
Keyword(s):  
Mathematical Model ◽  
Alcohol Consumption ◽  
Liver Injury ◽  
Protective Effect ◽  
The Body ◽  
Chronic Alcohol ◽  
Single Time ◽  
Apap Overdose ◽  
Increased Risk

AbstractAcetaminophen (APAP) overdose is one of the predominant causes of drug induced acute liver injury in the U.S and U.K. Clinical studies show that ingestion of alcohol may increase the risk of APAP induced liver injury. Chronic alcoholism may potentiate APAP hepatotoxicity and this increased risk of APAP toxicity is observed when APAP is ingested even shortly after alcohol is cleared from the body. However, clinical reports also suggest that acute alcohol consumption may have a protective effect against hepatotoxicity by inhibiting microsomal acetaminophen oxidation and thereby reducing N-acetyl-p-benzoquinone imine (NAPQI) production. The aim of this study is to model this dual role of alcohol to determine how the timing of alcohol ingestion affects APAP metabolism and resulting liver injury and identify mechanisms of APAP induced liver injury. The mathematical model is developed to capture condition of a patient of single time APAP overdose who may be an acute or chronic alcohol user. The analysis suggests that the risk of APAP-induced hepatotoxicity is increased if APAP is ingested shortly after alcohol is cleared from the body in chronic alcohol users. A protective effect of acute consumption of alcohol is also observed in patients with APAP overdose. For example, simultaneous ingestion of alcohol and APAP overdose or alcohol intake after or before few hours of APAP overdose may result in less APAP-induced hepatotoxicity when compared to a single time APAP overdose. The rate of hepatocyte damage in APAP overdose patients depends on trade-off between induction and inhibition of CYP enzyme.

PTU-107 Real-time, intravital imaging of paracetamol-induced acute liver injury: a novel approach

2017 ◽  
Author(s):  
AI Thompson ◽  
K Conroy ◽  
M Lee ◽  
K Simpson ◽  
J Iredale ◽  
...  
Keyword(s):  
Liver Injury ◽  
Real Time ◽  
Acute Liver Injury ◽  
Intravital Imaging ◽  
Novel Approach

Multi-layer pattern creation for seamless front female body armor panel using angle-interlock woven fabrics

2016 ◽  
Vol 87 (3) ◽  
pp. 381-386 ◽  
Author(s):  
D Yang ◽  
X Chen
Keyword(s):  
Mathematical Model ◽  
Female Body ◽  
Woven Fabrics ◽  
The Body ◽  
Body Armor ◽  
Woven Fabric ◽  
Front Panel ◽  
Ballistic Performance ◽  
Novel Approach ◽  
The Relationship

Angle-interlock woven fabric offers an option for making female body armor as it can form integrally the required dome shapes because of its extraordinary moldability and satisfactory ballistic performance. A mathematical model is created to determine the pattern geometry for the front panel of female body armor, and the front panel can be quickly created using this mathematical model. However, the body armor is multi-layer, which indicates that the relationship between the thickness of the fabric and the pattern block projection for different layers of fabric needs to be investigated, in order to create the whole panel, to improve this novel approach for making seamless female body armor with satisfactory ballistic performance.

scholarly journals Combining Physiology-Based Modeling and Evolutionary Algorithms for Personalized, Noninvasive Cardiovascular Assessment Based on Electrocardiography and Ballistocardiography

2022 ◽  
Vol 12 ◽  
Author(s):  
Nicholas Mattia Marazzi ◽  
Giovanna Guidoboni ◽  
Mohamed Zaid ◽  
Lorenzo Sala ◽  
Salman Ahmad ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Mathematical Model ◽  
Blood Pressure Measurement ◽  
Model Parameters ◽  
Cardiovascular Monitoring ◽  
Cardiovascular Parameters ◽  
Physiological Variables ◽  
Novel Approach ◽  
Cardiovascular Assessment ◽  
Parameter Values

Purpose: This study proposes a novel approach to obtain personalized estimates of cardiovascular parameters by combining (i) electrocardiography and ballistocardiography for noninvasive cardiovascular monitoring, (ii) a physiology-based mathematical model for predicting personalized cardiovascular variables, and (iii) an evolutionary algorithm (EA) for searching optimal model parameters.Methods: Electrocardiogram (ECG), ballistocardiogram (BCG), and a total of six blood pressure measurements are recorded on three healthy subjects. The R peaks in the ECG are used to segment the BCG signal into single BCG curves for each heart beat. The time distance between R peaks is used as an input for a validated physiology-based mathematical model that predicts distributions of pressures and volumes in the cardiovascular system, along with the associated BCG curve. An EA is designed to search the generation of parameter values of the cardiovascular model that optimizes the match between model-predicted and experimentally-measured BCG curves. The physiological relevance of the optimal EA solution is evaluated a posteriori by comparing the model-predicted blood pressure with a cuff placed on the arm of the subjects to measure the blood pressure.Results: The proposed approach successfully captures amplitudes and timings of the most prominent peak and valley in the BCG curve, also known as the J peak and K valley. The values of cardiovascular parameters pertaining to ventricular function can be estimated by the EA in a consistent manner when the search is performed over five different BCG curves corresponding to five different heart-beats of the same subject. Notably, the blood pressure predicted by the physiology-based model with the personalized parameter values provided by the EA search exhibits a very good agreement with the cuff-based blood pressure measurement.Conclusion: The combination of EA with physiology-based modeling proved capable of providing personalized estimates of cardiovascular parameters and physiological variables of great interest, such as blood pressure. This novel approach opens the possibility for developing quantitative devices for noninvasive cardiovascular monitoring based on BCG sensing.

scholarly journals Affective Multimodal Control of Virtual Characters

2020 ◽  
Vol 6 (4) ◽  
pp. 43-54 ◽  
Author(s):  
Martin Klesen ◽  
Patrick Gebhard
Keyword(s):  
Real Time ◽  
The Body ◽  
Temporal Constraints ◽  
Virtual Characters ◽  
Fine Grained ◽  
Novel Approach ◽  
Control Body ◽  
High Level ◽  
The Mind ◽  
Selection Of

In this paper we report about the use of computer generated affect to control body and mind of cognitively modeled virtual characters. We use the computational model of affect ALMA that is able to simulate three different affect types in real-time. The computation of affect is based on a novel approach of an appraisal language. Both the use of elements of the appraisal language and the simulation of different affect types has been evaluated. Affect is used to control facial expressions, facial complexions, affective animations, posture, and idle behavior on the body layer and the selection of dialogue strategies on the mind layer. To enable a fine-grained control of these aspects a Player Markup Language (PML) has been developed. The PML is player-independent and allows a sophisticated control of character actions coordinated by high-level temporal constraints. An Action Encoder module maps the output of ALMA to PML actions using affect display rules. These actions drive the real-time rendering of affect, gesture and speech parameters of virtual characters, which we call Virtual Humans. 

scholarly journals Enabling real-time applications in Wi-Fi networks

2019 ◽  
Vol 15 (5) ◽  
pp. 155014771984531 ◽  
Author(s):  
Dmitry Bankov ◽  
Evgeny Khorov ◽  
Andrey Lyakhov ◽  
Mark Sandal
Keyword(s):  
Mathematical Model ◽  
Virtual Reality ◽  
Remote Control ◽  
Real Time ◽  
Packet Loss ◽  
Loss Ratio ◽  
High Importance ◽  
Real Time Traffic ◽  
Novel Approach ◽  
Real Time Applications

Being of high importance, real-time applications, such as online gaming, real-time video streaming, virtual reality, and remote-control drone and robots, introduce many challenges to the developers of wireless networks. Such applications pose strict requirements on the delay and packet loss ratio, and it is hardly possible to satisfy them in Wi-Fi networks that use random channel access. The article presents a novel approach to enable real-time communications by exploiting an additional radio. This approach was recently proposed by us in the IEEE 802.11 Working Group and attracted much attention. To evaluate its gain and to study how real-time traffic coexists with the usual one, a mathematical model is designed. The numerical results show that the proposed approach allows decreasing the losses and delays for the real-time traffic by orders of magnitude, while the throughput for the usual traffic is reduced insignificantly in comparison to existing networks.

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