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Optimization of Blood Supply Chain
, M.Sc. Thesis Sharif University of Technology ; Kianfar, Farhad (Supervisor)
Abstract
Blood is a perishable product and can only be stored for a limited time. Reducing the level of wastage and shortage in supply chain of blood products is the main challenge of supply chain management. Wastage occurs whenever hospitals and blood banks order excessive blood while ordering insufficient amount results in shortage. Wastage can increase the costs in supply chain while shortage can cause important operation to be cancelled.This thesis presents an integer programming model for improving blood related operations in hospitals and blood banks. The presented model determines optimal order levels for each period which minimize total cost, shortage and wastage levels. The model is...
Investigation of Mechanical Properties of Healthy Red Blood Cells using Optical Tweezers
, M.Sc. Thesis Sharif University of Technology ; Seyed Reihani, Nader (Supervisor) ; Moosavi-Movahhedi, Ali Akbar (Co-Advisor)
Abstract
Red blood cells (RBC, erythrocytes) are cells with an average diameter of 8 microns, the thickness of 2-3 microns and the volume of 90 fl. The biconcave shape of red blood cells,together with cell membrane flexibility, enables them to pass the capillaries whose diameter is considerably less than 8 micrometers. Mechanical properties of RBC are related to their membrane and cytoskeleton, which consists of spectrin network. Optical tweezers is able to exert very precise forces to erythrocytes using beed as a handle. In this report, we studied mechanical properties of RBC such as elasticity and viscoelasticity using single trap optical tweezers with beads with antibody coated in order to attach...
Investigating the Effect of Hemoglobin on Viscoelastic Properties of RBC
, M.Sc. Thesis Sharif University of Technology ; Seyed Reihani, Nader (Supervisor)
Abstract
Red blood cells are one of the most important parts of blood and their mechanical properties are so important in some diseases. Red blood cell is mostly consisted of membrane, cell skeleton, and cytoplasm which contains hemoglobin proteins. Studying these properties separately not only could give us pieces of information about cell mechanics, but also reveals a way to predict their behavior after illnesses. Optical tweezers as a tool, which can produce and measure Piconewton to Nanonewton forces, has been interesting in red blood cell parts' studying. In this thesis, at first hemoglobin is taken out gradually by using Saponin (which is enable to make some pores in the membrane) and the...
Management and Treatment of Diabetes Artificial Neural Networks Controllers
, M.Sc. Thesis Sharif University of Technology ; Seifipour, Navid (Supervisor)
Abstract
Diabetes is a global problem as a silent epidemic disorder. Diabetes Mellitus has involved at least five percent of our population. It will cause so many complications and end-organs effects if it is not controlled. Today, treatment and control of diseases using computational intelligent systems has been paid a lot of attention to. That’s why this study has taken treatment and control of diabetes into consideration. So, the neural networks have been used to manage and treat diabetes. To do this, real data from diabetic patients has been gathered and based on the data, a model has been obtained to show the effect of insulin on the amount of blood glucose. Then, a neural network controller has...
The Effect of Thyroid Hormones on The Viscoelastic Behavior of Red Blood Cells
, M.Sc. Thesis Sharif University of Technology ; Seyed Reihani, Nader (Supervisor)
Abstract
Blood is one of the most important fluids in the human body, consisting of three parts: red blood cells, white blood cells and platelets. The mechanical properties of red blood cells are important in many diseases. The study of viscosity and other mechanical properties of red blood cells in recent years has attracted the attention of scientists in this field. The mechanical properties of red blood cells are related to the outer membrane and its cytoskeleton, and the study of these components can predict the behavior of red blood cells in diseases. The thyroid gland is located in front of the neck and secretes hormones that control many chemical processes in different parts of the body....
Validation of the Saadat NIBP module according to the ANSI/AAMI-SP10 protocol
, Article 2013 20th Iranian Conference on Biomedical Engineering, ICBME 2013 ; Deembec , 2013 , Pages 199-202 ; Mashayekhi, G ; Behzadfar, N ; Yaghoobzadeh, A ; Babaee, T ; Sharif University of Technology
IEEE Computer Society
2013
Abstract
This study is conducted with the aim of validating the Saadat non-invasive blood pressure (NIBP) module accuracy and reliability against direct intra arterial pressure measurement (IBP) according to the ANSI/AAMI SP10-2002 guidelines. Measurement and comparison procedure were done in a static population of 19 adult patients with brachial catheterized arterial line with total measurements of 195 under supervision of a highly experienced cardiovascular anesthesiologist in accordance with the ANSI/AAMI SP10-2002 regulation. Data analysis was performed based on the protocol criteria. In order to represent relationships between the test device and the reference method, Bland-Altman graphical...
Pulsatile blood flow in total cavopulmonary connection: a comparison between Y-shaped and T-shaped geometry
, Article Medical and Biological Engineering and Computing ; Volume 55, Issue 2 , 2017 , Pages 213-224 ; 01400118 (ISSN) ; Firoozabadi, B ; Saidi, M. S ; Monjezi, M ; Navabi Shirazi, M. A ; Malakan Rad, E ; Sharif University of Technology
Springer Verlag
2017
Abstract
Single-ventricle anomaly is a hereditary heart disease that is characterized by anatomical malformations. The main consequence of this malformation is desaturated blood flow, which without proper treatment increases the risk of death. The classical treatment is based on a three-stage palliative procedure which should begin from the first few days of patient’s life. The final stage is known as Fontan procedure, in which inferior vena cava is directly connected to pulmonary arteries without going through the ventricle. This connection is called total cavopulmonary connection (TCPC). After surgery, the single ventricle supplies adequate and saturated systemic blood flow to the body; however,...
Malignancy determination of tumors using perfusion MRI
, Article 2009 International Conference on Image Processing, Computer Vision, and Pattern Recognition, IPCV 2009, Las Vegas, NV, 13 July 2009 through 16 July 2009 ; Volume 2 , 2009 , Pages 906-909 ; 9781601321190 (ISBN) ; Soltanian Zadeh, H ; Akhlaghpour, S ; Fatemi Zadeh, E ; United States Military Academy, Network Science Center; HST Harvard Univ. MIT, Biomed. Cybern. Lab.; Argonne's Leadersh. Comput. Facil. Argonne Natl. Lab.; Univ. Illinois Urbana-Champaign, Funct. Genomics Lab.; University of Minnesota, Minnesota Supercomputing Institute ; Sharif University of Technology
2009
Abstract
Our purpose was to determine whether perfusion MR imaging can be used for malignancy determination of tumors. Relative cerebral blood flow (rCBF) is a commonly used perfusion magnetic resonance imaging (MRI) technique for the evaluation of malignancy. The goal of our study was to determine the usefulness of this parameter in malignancy determination of tumors using Independent Component Analysis (ICA)
Single-replicate longitudinal data analysis in the presence of multiple instrumental measurement errors
, Article Computers and Industrial Engineering ; Volume 141 , 2020 ; Behbahani, M ; Khedmati, M ; Akhavan Niaki, S. T ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
In this paper, a novel method as a combination of the expectation–maximization (EM) algorithm and Variogram is proposed to decompose the longitudinal measurement errors in the absence of replications and the presence of multiple instrumental measurement errors. In the proposed method, multiple measurements are considered where the units are observed by several distinct instruments (gauges). The approach decouples the observed variance of the measurement model into the process and measurement system variances. In addition, it decomposes the variance of multiple instruments into the process and instrument variances. In the end, the proposed model is validated and tested based on simulated...
Designing an efficient blood supply chain network in crisis: neural learning, optimization and case study
, Article Annals of Operations Research ; Volume 289, Issue 1 , 30 October , 2020 , Pages 123-152 ; Soltanzadeh, S ; Weber, G. W ; Roy, S. K ; Sharif University of Technology
Springer
2020
Abstract
In recent years, attention to blood supply chain in disaster circumstances has significantly increased. Disasters, especially earthquakes, have adverse consequences such as destruction, loss of human lives, and undermining the effectiveness of health services. This research considers a six-echelon blood supply chain which consists of donors, blood collection centers (permanent and temporary), regional blood centers, local blood centers, regional hospitals, and local hospitals. For the first time, we considered that helicopters could carry blood from regional hospitals to local hospitals and return injured people that cannot be treated in local hospitals to regional hospitals due to the...
Time-dependent analysis of leaflets in mechanical aortic bileaflet heart valves in closing phase using the finite strip method
, Article Medical Engineering and Physics ; Volume 28, Issue 2 , 2006 , Pages 122-133 ; 13504533 (ISSN) ; Ahmadian, M. T ; Wan, W. K ; Sharif University of Technology
2006
Abstract
Background and aims of the study: Mechanical heart valves (MHV) are widely used to replace dysfunctional and failed heart valves. The bileaflet MHV design is very popular due to its superior hemodynamics. Since their introduction in 1977, the hemodynamics of bileaflet prostheses has been extensively studied. In this study the dynamic behaviour during the closing phase of a bileaflet MHV under normal physiological conditions has been investigated. Methods: Fluid analysis is based on the control volume with moving boundaries in the vicinity of the occluder. Unsteady continuity equation, unsteady momentum equation on the control volume and unsteady Bernoulli's equation have been used to...
Prevascularized micro-/nano-sized spheroid/bead aggregates for vascular tissue engineering
, Article Nano-Micro Letters ; Volume 13, Issue 1 , 2021 ; 23116706 (ISSN) ; Nasrollahi Boroujeni, N ; Jahangiri, S ; Rabiee, N ; Rabiee, M ; Makvandi, P ; Akhavan, O ; Varma, R. S ; Sharif University of Technology
Springer Science and Business Media B.V
2021
Abstract
Efficient strategies to promote microvascularization in vascular tissue engineering, a central priority in regenerative medicine, are still scarce; nano- and micro-sized aggregates and spheres or beads harboring primitive microvascular beds are promising methods in vascular tissue engineering. Capillaries are the smallest type and in numerous blood vessels, which are distributed densely in cardiovascular system. To mimic this microvascular network, specific cell components and proangiogenic factors are required. Herein, advanced biofabrication methods in microvascular engineering, including extrusion-based and droplet-based bioprinting, Kenzan, and biogripper approaches, are deliberated with...
A Closed-Loop Model for Green Blood Supply Chain Considering Supply and Demand Uncertainty
, M.Sc. Thesis Sharif University of Technology ; Akhavan Niaki, Taghi (Supervisor)
Abstract
Blood is a very valuable material for the life of human beings and should be transfused to the patient as soon as possible in case of necessity. It is s perishable product and different blood products have different shelf lives. Therefore, it is important to manage properly blood product inventories in hospitals to avoid shortage and outdate as much as possible. In this research, a bi-objective mixed-integer programming model is developed which aims to simultaneously minimize the total cost of the supply chain network and the total environmental impacts of the activities of the supply chain network. Since the nature of the problem is uncertain, a robust possibilistic programming approach is...
Metabonomics exposes metabolic biomarkers of Crohn's disease by 1HNMR
, Article Gastroenterology and Hepatology from Bed to Bench ; Volume 6, Issue SUPPL , 2013 , Pages S19-S22 ; 2008-4234 (EISSN) ; Ektefa, F ; Hagh-Azali, M ; Aghdaie, H. A ; Sharif University of Technology
2013
Abstract
Metabonomics and other "omic" fields are essential science in analytical chemistry. Modern analytical instruments such as proton nuclear magnetic resonance (1H-NMR) can provide the great quantity of analytical information. In order to assign unknown samples, chemometric methods recognition build classification model based on experimental data. Firstly, some current strategies regarding disease diagnosis are exhibited in metabonomic studies. Some diseases such as crohn's disease can be difficult to diagnose since its signs and symptoms may be similar to other medical problems or often mimic other symptoms. Applications of NMR and supervised pattern recognition in the field of metabonomics are...
Simulation of red blood cell deformation in microvessels using a new rapid modified particle method
, Article ASME 2011 International Mechanical Engineering Congress and Exposition, IMECE 2011, 11 November 2011 through 17 November 2011 ; Volume 6, Issue PARTS A AND B , November , 2011 , Pages 1087-1090 ; 9780791854921 (ISBN) ; Ahmadian, M. T ; Hasanian, M ; Samiezadeh, S ; Sharif University of Technology
Abstract
The deformation of human red blood cell has been a topic of considerable scientific interest and real-life significance. Several methods have been improved to simulate the behavior of red blood cells motion and deformation in micro-capillaries. Since in microscopic scales, using discrete models are more preferred than continuum methods, moving particle semiimplicit method (MPS) which is one of the recent innovative particle based methods, can simulate micro-fluidic flows based on Navier-Stocks equations. It has been shown that original MPS method has a lack of rapid calculation which leads to massive calculations and long time simulation. Quite a few studies have been done to improve MPS...
A fuzzy expert system for prescribing atorvastatin optimum dose
, Article Koomesh ; Volume 13, Issue 1 , 2011 , Pages 43-50 ; 16087046 (ISSN) ; Hassanpour Ezatti, M ; Navidi, H ; Abachi, T ; Sharif University of Technology
2011
Abstract
Introduction: Today, Fuzzy expert systems have helped physicians in cases of uncertainty in medical decision making for prescribing drugs. Narrowing of coronary heart and reduction in heart blood flow are important causes of coronary heart disease (CHD). Control of blood lipid level is a routine treatment in CHD patients. But damage to liver is a common side effect of lipid lowering drug medication. Measurement of plasma Alanine aminotransferase level is considered as a marker of liver damage. The aim of this study was to determination of optimal dose of atorvastatin using Fuzzy expert system. Materials and Methods: in this study, Fuzzy expert system based on drug dose determination was...
Prediction of acute hypotension episodes using Logistic Regression model and Support Vector Machine: A comparative study
, Article 2011 19th Iranian Conference on Electrical Engineering, ICEE 2011, 17 May 2011 through 19 May 2011 ; May , 2011 , Page(s): 1 - 4 ; ISSN :21647054 ; 9789644634284 (ISBN) ; Arasteh, A ; Moradi, M. H ; Sharif University of Technology
2011
Abstract
Acute hypotension episodes are one of the hemodynamic instabilities with high mortality rate that is frequent among many groups of patients. Prediction of acute hypotension episodes can help clinicians to diagnose the cause of this physiological disorder and select proper treatment based on this diagnosis. In this study new physiological time series are generated based on heart rate, systolic blood pressure, diastolic blood pressure and mean blood pressure time series. Statistical features of these time series are extracted and patients whom are exposed to acute hypotension episodes in future 1 hour time interval and whom are not, are classified based on these features and with the aid of...
Optimizing fuzzy logic controller for diabetes type I by genetic algorithm
, Article 2010 The 2nd International Conference on Computer and Automation Engineering, ICCAE 2010, 26 February 2010 through 28 February 2010, Singapore ; Volume 2 , 2010 , Pages 4-8 ; 9781424455850 (ISBN) ; Azizi, A ; Sharif University of Technology
2010
Abstract
Biological systems are highly nonlinear, and there is a significant amount of variability from one patient to another. A controller for drug infusion has to be able to achieve good performance for most of the potential patient population. These controllers are designed for the general population, as no knowledge is available before hand for each particular patient. This necessitates perforce an algorithm that will be able to compensate for the differences between individuals and external factors. Of the possibilities, fuzzy logic direct model reference adaptive control (DMRAC) is the choice for Insulin infusion control for diabetes type I as results presented herein. Safety and robustness...
Nonlinear cuffless blood pressure estimation of healthy subjects using pulse transit time and arrival time
, Article IEEE Transactions on Instrumentation and Measurement ; Volume 66, Issue 12 , 2017 , Pages 3299-3308 ; 00189456 (ISSN) ; Kachuee, M ; Shabany, M ; Sharif University of Technology
Abstract
This paper presents a novel blood pressure (BP) estimation method based on pulse transit time (PTT) and pulse arrival time (PAT) to estimate the systolic BP (SBP) and the diastolic BP (DBP). A data acquisition hardware is designed for high-resolution sampling of phonocardiogram (PCG), photoplethysmogram, and electrocardiogram (ECG). PCG and ECG perform as the proximal timing reference to obtain PTT and PAT indices, respectively. In order to derive a BP estimator model, a calibration procedure, including a supervised physical exercise, is conducted for each individual, which causes changes in their BP, and then, a number of reference BPs are measured alongside the acquisition of the signals...
Non-invasive blood pressure estimation using phonocardiogram
, Article Proceedings - IEEE International Symposium on Circuits and Systems, 28 May 2017 through 31 May 2017 ; 2017 ; 02714310 (ISSN) ; 9781467368520 (ISBN) ; Kachuee, M ; Shabany, M ; Sharif University of Technology
Abstract
This paper presents a novel approach based on pulse transit time (PTT) for the estimation of blood pressure (BP). In order to achieve this goal, a data acquisition hardware is designed for high-resolution sampling of phonocardiogram (PCG) and photoplethysmogram (PPG). These two signals can derive PTT values. Meanwhile, a force-sensing resistor (FSR) is placed under the cuff of the BP reference device to mark the moments of measurements accurately via recording instantaneous cuff pressure. For deriving the PTT-BP models, a calibration procedure including a supervised physical exercise is conducted for each individual. The proposed method is evaluated on 24 subjects. The final results prove...