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Full-Text Articles in Medicine and Health Sciences

Modeling An Infection Outbreak With Quarantine: The Sibkr Model, Mikenna Dew, Amanda Langosch, Theadora Baker-Wallerstein Apr 2024

Modeling An Infection Outbreak With Quarantine: The Sibkr Model, Mikenna Dew, Amanda Langosch, Theadora Baker-Wallerstein

Rose-Hulman Undergraduate Mathematics Journal

Influenza is a respiratory infection that places a substantial burden in the world population each year. In this project, we study and interpret a data set from a flu outbreak in a British boarding school in 1978 with mathematical modeling. First, we propose a generalization of the SIR model based on the quarantine measure in place and establish the long-time behavior of the model. By analyzing the model mathematically, we determine the analytic formulas of the basic reproduction number, the long-time limit of solutions, and the maximum number of infection population. Moreover, we estimate the parameters of the model based …


Analyzing The Influence Of Design And Operating Conditions On Combustion And Emissions In Premixed Turbulent Flames: A Comprehensive Review, Medhat Elkelawy Prof. Dr. Eng., E. A. El Shenawy Prof. Dr., Hagar Alm-Eldin Bastawissi, Ibrahim Ali Mousa Eng., Mohamed M. Abdel-Raouf Ibrahim Dr. Eng. Mar 2024

Analyzing The Influence Of Design And Operating Conditions On Combustion And Emissions In Premixed Turbulent Flames: A Comprehensive Review, Medhat Elkelawy Prof. Dr. Eng., E. A. El Shenawy Prof. Dr., Hagar Alm-Eldin Bastawissi, Ibrahim Ali Mousa Eng., Mohamed M. Abdel-Raouf Ibrahim Dr. Eng.

Journal of Engineering Research

Recently, premixed combustion has dominated the field of combustion research worldwide. The current work is a review that addresses the effects of design and operating regimes on the combustion and emission characteristics of premixed turbulent flames. The study accounts for recent developments aimed at overcoming combustor operability issues that influence emissions and flame stability. Various experimental setups have been utilized in investigations, with results pertaining to performance and emissions concerning premixed turbulent flames. Thus, the objective of this paper is to provide a comprehensive review of the effects of swirl vane angles and equivalence fuel-air ratios for tests conducted both …


Building For Safety: Design Considerations For Refuge Areas In Tall Buildings From Quality Management Perspective, Enass. A. Salama, Heba. M. Gaber, Ahmed. M. Selim Mar 2024

Building For Safety: Design Considerations For Refuge Areas In Tall Buildings From Quality Management Perspective, Enass. A. Salama, Heba. M. Gaber, Ahmed. M. Selim

Journal of Engineering Research

New El Alamein City is one of the largest urban projects in Egypt, and the largest project on the north coast. Tall buildings (super high-rise buildings) are considered the prevailing trend by architectural designers to obtain the maximum view of the Mediterranean Sea. The provision of safety evacuation in emergencies for these buildings’ occupants is a crucial challenge from the Quality management point of view. In contrast, there are no sufficient architectural design guidelines for the tall buildings provided by the Egyptian code for protecting buildings from fire, especially the design of the refuge areas. This study aims to investigate …


Effect Of Organic Compounds Additives For Biodiesel Fuel Blends On Diesel Engine Vibrations And Noise Characteristics, Medhat Elkelawy Prof. Dr, Eng., Hagar Alm-Eldin Bastawissi Prof. Dr. Eng., E. A. El Shenawy Prof. Dr., Mahmoud Soliman Eng. Mar 2024

Effect Of Organic Compounds Additives For Biodiesel Fuel Blends On Diesel Engine Vibrations And Noise Characteristics, Medhat Elkelawy Prof. Dr, Eng., Hagar Alm-Eldin Bastawissi Prof. Dr. Eng., E. A. El Shenawy Prof. Dr., Mahmoud Soliman Eng.

Journal of Engineering Research

The extensive consumption of petroleum fuel directly correlates with both hazardous exhaust emissions affecting human health and contributing to global warming. Initially, biodiesel fuels were proposed as a viable alternative to address these issues. This perspective finds support in numerous published studies that highlight how the significant catalytic effect of nanoparticles allows for their integration into biodiesel blends, resulting in improved combustion characteristics, reduced exhaust emissions, and enhanced performance. This study investigates the impact of additives on biodiesel fuel properties and its effects on engine performance metrics such as brake power, brake thermal efficiency, exhaust gas concentration, engine vibration, and …


Investigation Into The Impact Of Ammonia Hydroxide On Performance And Emissions In Compression Ignition Engines Utilizing Diesel/Biodiesel Blends, Medhat Elkelawy Prof. Dr, Eng., Hagar Alm-Eldin Bastawissi, Mohammed Osama Elsamadony Dr. Eng., Abdallah Salem Abdalhadi Mar 2024

Investigation Into The Impact Of Ammonia Hydroxide On Performance And Emissions In Compression Ignition Engines Utilizing Diesel/Biodiesel Blends, Medhat Elkelawy Prof. Dr, Eng., Hagar Alm-Eldin Bastawissi, Mohammed Osama Elsamadony Dr. Eng., Abdallah Salem Abdalhadi

Journal of Engineering Research

In recent times, there has been a surge in scientific endeavors aimed at combating global warming. Various methods have been employed to address this issue, including the substitution of fossil fuels with more environmentally sustainable alternatives and the combination of different fuel types. This can be achieved through the integration of innovative injection systems and the simultaneous combustion of alternative fuels alongside fossil fuels, or by modifying fuel injection systems such as in the PCCI, RCCI, or HCCI systems. In a particular research investigation, a blend of ammonia hydroxide and diesel, with volume percentages of 7.5% and 92.5% respectively, was …


Enhancing Diesel Engine Performance By Directly Injecting Blends Of Ammonium Hydroxide And Including Liquid Petroleum Gas As A Partially Premixed Charge, Medhat Elkelawy Prof. Dr, Eng., Hagar Alm-Eldin Bastawissi, Mohammed Osama Elsamadony Dr. Eng., Abdallah Salem Abdalhadi Mar 2024

Enhancing Diesel Engine Performance By Directly Injecting Blends Of Ammonium Hydroxide And Including Liquid Petroleum Gas As A Partially Premixed Charge, Medhat Elkelawy Prof. Dr, Eng., Hagar Alm-Eldin Bastawissi, Mohammed Osama Elsamadony Dr. Eng., Abdallah Salem Abdalhadi

Journal of Engineering Research

Recently, scientists have made significant strides in addressing or mitigating environmental issues. Researchers have adopted various approaches to tackle these issues, such as replacing fossil fuels with more environmentally friendly alternatives or blending multiple fuel types. This can be achieved by either integrating these two trends through the use of new injection systems and simultaneous combustion of alternative fuels with fossil fuels or by modifying fuel injection systems, exemplified by the PCCI, RCCI, or HCCI systems. Consequently, these methods have proven effective in reducing environmental pollutants, enhancing thermal efficiency, and decreasing specific fuel consumption. In this study, ammonia hydroxide and …


Experimental Investigation On Combustion And Emission Characteristics Of Co-Combustion Of Pulverized Biomass With Diesel Fuel In An Industrial Burner, Medhat Elkelawy Prof. Dr, Eng., Hagar Alm-Eldin Bastawissi, Ahmed Abou El-Yazied Prof. Dr., Saad El-Malla Dr. Eng. Mar 2024

Experimental Investigation On Combustion And Emission Characteristics Of Co-Combustion Of Pulverized Biomass With Diesel Fuel In An Industrial Burner, Medhat Elkelawy Prof. Dr, Eng., Hagar Alm-Eldin Bastawissi, Ahmed Abou El-Yazied Prof. Dr., Saad El-Malla Dr. Eng.

Journal of Engineering Research

This study presents the combustion and emission results obtained from a laboratory furnace equipped with a 35 kW industrial burner that utilizes co-combustion of pulverized biomass and diesel fuel. The experiment compared the co-combustion of pulverized biomass and diesel fuel with diesel fuel alone. Three different loading ratios of pulverized biomass from residual beet samples were used. Temperatures were measured at various positions inside the furnace to analyze combustion performance. It was observed that increasing the biomass loading ratios led to higher flame temperatures and improved combustion compared to diesel fuel alone. The concentrations of pollutants such as Co, HC, …


Cfd Study On Two-Phase Flow Patterns In A Pipe With 90º Elbow In Different Operating Conditions, Hagar Alm-Eldin Bastawissi, Mohammed Ahmed Khafagy, E. A. El Shenawy Prof. Dr., Ahmed M. Salem Dr Mar 2024

Cfd Study On Two-Phase Flow Patterns In A Pipe With 90º Elbow In Different Operating Conditions, Hagar Alm-Eldin Bastawissi, Mohammed Ahmed Khafagy, E. A. El Shenawy Prof. Dr., Ahmed M. Salem Dr

Journal of Engineering Research

Recently, CFD has offered a technological solution for modelling multi-phase flow in which we can make endless simulations with reduced expenses and effort in high accuracy results; we shall also mention that experimental studies have limitations for safety considerations when experimenting with flow in high temperature or pressure values or medium nature as in nuclear or chemical flows.In this paper, we used the ANSYS FLUENT CFD program to simulate the two-phase flow in a pipe to study the effect of attaching a 90-degree elbow fitting to the piping system, seeking to find out the change in the pattern and resulting …


تقنيات الاضاءة الصناعية وتأثيرها فى الفراغ السكنى على السلوك الانسانى, Samah Kamal Elfeky, Walaa Ahmad Nour, Lobna Abdelfatah Agha Mar 2024

تقنيات الاضاءة الصناعية وتأثيرها فى الفراغ السكنى على السلوك الانسانى, Samah Kamal Elfeky, Walaa Ahmad Nour, Lobna Abdelfatah Agha

Journal of Engineering Research

* Lighting is considered of main items in daily life begining from natural Lighting to industrial lighting. with all of it's different shapes . it is considerdone of the most important data that point Blank spaces and works to show architectural spaces, aesthetic values through being sharp and weak, ensure borders show texture or hide Features, suggest wideness, narrowness of space as the most beautiful design don't see beautiful without good lighting which designed carefully.Due to diversity of human activities, architictums spaces and it is wideness. Increased dependence on industrial Lighting to strengthen Job of performance, beauty of internal, external …


A Tale Of Two Viruses: Why Smallpox Was Eradicated And Polio Persists, Katherine G. Mcgough, Erin N. Bodine Jan 2024

A Tale Of Two Viruses: Why Smallpox Was Eradicated And Polio Persists, Katherine G. Mcgough, Erin N. Bodine

Spora: A Journal of Biomathematics

The smallpox and poliomyelitis (polio) viruses were, at a time, one of the largest threats to global public health killing millions until global eradication campaigns were put into effect. Vaccination led to the eradication of smallpox and the elimination of polio for most of the world. However, polio continues to persist at endemic levels in Pakistan and Afghanistan. We developed ODE models of smallpox and polio to explore differences in transmission dynamics and determine if the underlying biology has made poliomyelitis more difficult to eradicate. Our model analysis shows there are multiple factors which should allow polio to have a …


The Influence Of Green Building Design On Tourists' Intention To Stay In Eco-Friendly Hotels: A Study On Perceptions And Preferences, Enas Al Sayed Salama Dr., Gehad Nasr Abdelsalam Dr. Jan 2024

The Influence Of Green Building Design On Tourists' Intention To Stay In Eco-Friendly Hotels: A Study On Perceptions And Preferences, Enas Al Sayed Salama Dr., Gehad Nasr Abdelsalam Dr.

Journal of Engineering Research

Green building design involves integrating sustainable and environmentally friendly practices into the construction and operation of buildings, including hotels, with the goal of minimizing the adverse impact on the environment. This paper delves into the pivotal role of green building design and eco-service provision within the context of green hotels. The aim is to investigate the interconnections among tourists' environmental concerns, their perceived significance of green building design, and their intention to choose green hotels.

To enhance the understanding of tourist behavior and its implications for tourism in Egypt, a questionnaire was administered in Sharm El Sheikh, a prominent Egyptian …


Experimental Study Of Bent Glass Curtain Walls., Sarah Said Abd El Kariem, Moustafa El Shami, Mahmoud El Nagar Jan 2024

Experimental Study Of Bent Glass Curtain Walls., Sarah Said Abd El Kariem, Moustafa El Shami, Mahmoud El Nagar

Journal of Engineering Research

A Bent Laminated Glass is commonly used in the residential and commercial structures, its methodology is not present in the curves and tables at the ASTM E1300. Therefore, it has become a need for architects to use basis for this type of glass. To the best of authors ‘knowledge, no one study the bent laminated glass in details. A variety of safety glass that has lately gained popularity in the construction sector is modern laminated glass. Given that it offers a safe failover capability, it is perfect for the automotive industry. Double-lite glass is produced using two or more …


Market Analysis And Bidding Strategy Of Hybrid Renewable Energy Systems Considering Emissions, Fatma Elzahraa, Mohamed Elnemr, Samir Dawoud Jan 2024

Market Analysis And Bidding Strategy Of Hybrid Renewable Energy Systems Considering Emissions, Fatma Elzahraa, Mohamed Elnemr, Samir Dawoud

Journal of Engineering Research

The competition in the electricity markets makes it difficult to choose a suitable strategy for maximizing profit while reducing harmful emissions. To have an adequate energy price for consumers while minimizing the harmful emissions to the atmosphere and maximizing profits of all participants in the electricity market needs an aggressive bidding strategy. Developing these bidding strategies with the integration of renewable energy (RE) in the electricity market became important. This research studies various bidding strategies for maximizing profits in the deregulated energy market since participants are keen on developing bidding strategies considering emissions. These bidding strategies will consider the integration …


Effects Of Fuel Equivalence Ratio And Swirl Vane Angles On Premixed Burner Turbulent Flame Combustion Characteristics, Medhat Elkelawy Prof. Dr. Eng., E. A. El Shenawy Prof. Dr., Hagar Alm-Eldin Bastawissi Prof. Dr. Eng., Ibrahim Ali Mousa Eng., Mohamed M. Abdel-Raouf Ibrahim Dr. Eng. Jan 2024

Effects Of Fuel Equivalence Ratio And Swirl Vane Angles On Premixed Burner Turbulent Flame Combustion Characteristics, Medhat Elkelawy Prof. Dr. Eng., E. A. El Shenawy Prof. Dr., Hagar Alm-Eldin Bastawissi Prof. Dr. Eng., Ibrahim Ali Mousa Eng., Mohamed M. Abdel-Raouf Ibrahim Dr. Eng.

Journal of Engineering Research

A turbulent flow field has a major effect on the premixed flame structure and temperature distribution that specifically determines the effectiveness of the burned fuel and the amounts of produced emissions. However, the premixed flame tangential and axial velocity distribution through the flame length help to predict the combustion and emissions attributes of the burned fuel. In this regard, an experimental and analytical investigation on premixed turbulent burners at different equivalence fuel-air ratios with different swirl vane angles has been achieved in the present work to assess the combustion performance and emissions characteristics. A theoretical methodology was carried out to …


Enhancing The Performance Of Conventional Solar Still Using The Nano-Doped Paint (Ndp) Coating, Hagar Alm-Eldin Bastawissi Prof.Dr, Nermin Elgendy Engineer, Ayman R. El-Tohamy Jan 2024

Enhancing The Performance Of Conventional Solar Still Using The Nano-Doped Paint (Ndp) Coating, Hagar Alm-Eldin Bastawissi Prof.Dr, Nermin Elgendy Engineer, Ayman R. El-Tohamy

Journal of Engineering Research

Nations are throughout the entire globe continuously confronting the problem of potable water shortage. Recently, it has been thought that using solar energy to desalinate brackish water offers a practical answer to the world's water crises. The output of these stills, is meager, and academics haven't done much to boost it in any way. Solar distillers have been proposed as an efficient method to produce potable water. In recent years, saltwater has produced drinking water by various ways. The efficiency of a solar distiller is significantly influenced by various factors, most important factor of them is the absorber surface. In …


Engine Performance And Emissions Improvement Study On Direct Injection Of Diesel/Ammonia Dual Fuel By Adding Cng As Partially Premixed Charge, Medhat Elkelawy Prof. Dr, Eng., Hagar Alm-Eldin Bastawissi Prof. Dr., Mohammed Osama Elsamadony Dr. Eng., Abdallah Salem Abdalhadi Eng. Jan 2024

Engine Performance And Emissions Improvement Study On Direct Injection Of Diesel/Ammonia Dual Fuel By Adding Cng As Partially Premixed Charge, Medhat Elkelawy Prof. Dr, Eng., Hagar Alm-Eldin Bastawissi Prof. Dr., Mohammed Osama Elsamadony Dr. Eng., Abdallah Salem Abdalhadi Eng.

Journal of Engineering Research

Researchers have recently moved on in their studies to find a solution to prevent or reduce this problem. There have been directions taken by researchers to solve the problem, including, replacing fossil fuels with environmentally friendly types or by combining two or more types of fuel. This is by modifying fuel injection systems as appears in the PCCI, RCCI, or HCCI systems, or working to integrate the two trends by using new injection systems and burning alternative fuels with fossil fuels. Therefore, the trend has good results on the specific consumption of fuel, raising thermal efficiency, and working to reduce …


Experimental Study On The Impact Of Secondary Air Injection And Different Swirl Van Angles On Premixed Turbulent Flame Propagation And Emission Behaviors, Medhat Elkelawy Prof. Dr. Eng., E. A. El Shenawy Prof. Dr., Hagar Alm-Eldin Bastawissi Prof. Dr. Eng., Ibrahim Ali Mousa Eng., Mohamed M. Abdel-Raouf Ibrahim Dr. Eng. Jan 2024

Experimental Study On The Impact Of Secondary Air Injection And Different Swirl Van Angles On Premixed Turbulent Flame Propagation And Emission Behaviors, Medhat Elkelawy Prof. Dr. Eng., E. A. El Shenawy Prof. Dr., Hagar Alm-Eldin Bastawissi Prof. Dr. Eng., Ibrahim Ali Mousa Eng., Mohamed M. Abdel-Raouf Ibrahim Dr. Eng.

Journal of Engineering Research

The objective of the present paper is to investigate experimentally the flame characteristics utilizing different secondary air inlet direction for different primary air swirl numbers and equivalence fuel-air ratios. In this study, an experimental test rig was carried out to investigate the flame temperature and emission behavior with flame length at the equivalence fuel-air ratios taken0.96, 0.80, 0.70, and 0.60, and swirl vane angles were varied as 20, 30, 45, and 60° to generate different swirl numbers of 0.26, 0.416, 0.71 and 1.23, respectively. In addition to the introduction of secondary air in test combustor, whereas the primary air and …


The Effect Of An Existing Tunnel And A Newly Excavated Tunnel On Ground Loss Beneath Sand Slope-3d Numerical Study, Ashraf Nazir, Ahmed Nasr, Asmaa Saeed Jan 2024

The Effect Of An Existing Tunnel And A Newly Excavated Tunnel On Ground Loss Beneath Sand Slope-3d Numerical Study, Ashraf Nazir, Ahmed Nasr, Asmaa Saeed

Journal of Engineering Research

Abstract- Most researchers perform their numerical models for tunnels by modeling perfectly horizontal ground surfaces above the tunnels. The prediction of surface settlement of a sandy slope due to the interaction mechanism between the slope and the tunnels is one of the critical problems in urban areas. As a result, in this work, a numerical analysis using PLAXIS 3D TUNNEL has been performed to investigate the effect of tunnel excavation on the deformation of a shallow sandy slope, and empirically by the Herzog method. The study also assesses the influence of parameters on slope deformation that have not been …


Reducing Food Scarcity: The Benefits Of Urban Farming, S.A. Claudell, Emilio Mejia Dec 2023

Reducing Food Scarcity: The Benefits Of Urban Farming, S.A. Claudell, Emilio Mejia

Journal of Nonprofit Innovation

Urban farming can enhance the lives of communities and help reduce food scarcity. This paper presents a conceptual prototype of an efficient urban farming community that can be scaled for a single apartment building or an entire community across all global geoeconomics regions, including densely populated cities and rural, developing towns and communities. When deployed in coordination with smart crop choices, local farm support, and efficient transportation then the result isn’t just sustainability, but also increasing fresh produce accessibility, optimizing nutritional value, eliminating the use of ‘forever chemicals’, reducing transportation costs, and fostering global environmental benefits.

Imagine Doris, who is …


(R2032) Modeling The Effect Of Sanitation Effort On The Spread Of Carrier-Dependent Infectious Diseases Due To Environmental Degradation, Ram Naresh, Sandhya Rani Verma, J. B. Shukla, Manju Agarwal Jun 2023

(R2032) Modeling The Effect Of Sanitation Effort On The Spread Of Carrier-Dependent Infectious Diseases Due To Environmental Degradation, Ram Naresh, Sandhya Rani Verma, J. B. Shukla, Manju Agarwal

Applications and Applied Mathematics: An International Journal (AAM)

In this present study, an SIS model is proposed and analyzed to study the effect of sanitation effort in controlling the spread of carrier-dependent infectious disease in a human habitat due to environmental degradation. The dynamics of the model consist of six dependent variables, the susceptible population density, infective population density, carrier population density, cumulative density of environmental degradation and the density of sanitation effort applied on carrier population and degraded environment. In the modeling process, the carrier population density and sanitation effort are modeled logistically and the degradation of the environment is assumed to be directly proportional to the …


Du Undergraduate Showcase: Research, Scholarship, And Creative Works, Caitlyn Aldersea, Justin Bravo, Sam Allen, Anna Block, Connor Block, Emma Buechler, Maria De Los Angeles Bustillos, Arianna Carlson, William Christensen, Olivia Kachulis, Noah Craver, Kate Dillon, Muskan Fatima, Angel Fernandes, Emma Finch, Colleen Cassidy, Amy Fishman, Andrea Francis, Stacia Fritz, Simran Gill, Emma Gries, Rylie Hansen, Shannon Powers, Jacqueline Martinez, Zachary Harker, Ashley Hasty, Mykaela Tanino-Springsteen, Kathleen Hopps, Adelaide Kerenick, Colin Kleckner, Ci Koehring, Elijah Kruger, Braden Krumholz, Maddie Leake, Lyneé Alves, Seraphina Loukas, Yatzari Lozano Vazquez, Haley Maki, Emily Martinez, Sierra Mckinney, Mykaela Tanino-Springsteen, Audrey Mitchell, Kipling Newman, Audrey Ng, Megan Lucyshyn, Andrew Nguyen, Stevie Ostman, Casandra Pearson, Alexandra Penney, Julia Gielczynski, Tyler Ball, Anna Rini, Christina Rorres, Simon Ruland, Helayna Schafer, Emma Sellers, Sarah Schuller, Claire Shaver, Kevin Summers, Isabella Shaw, Madison Sinar, Claudia Pena, Apshara Siwakoti, Carter Sorensen, Madi Sousa, Anna Sparling, Alexandra Revier, Brandon Thierry, Dylan Tyree, Maggie Williams, Lauren Wols May 2023

Du Undergraduate Showcase: Research, Scholarship, And Creative Works, Caitlyn Aldersea, Justin Bravo, Sam Allen, Anna Block, Connor Block, Emma Buechler, Maria De Los Angeles Bustillos, Arianna Carlson, William Christensen, Olivia Kachulis, Noah Craver, Kate Dillon, Muskan Fatima, Angel Fernandes, Emma Finch, Colleen Cassidy, Amy Fishman, Andrea Francis, Stacia Fritz, Simran Gill, Emma Gries, Rylie Hansen, Shannon Powers, Jacqueline Martinez, Zachary Harker, Ashley Hasty, Mykaela Tanino-Springsteen, Kathleen Hopps, Adelaide Kerenick, Colin Kleckner, Ci Koehring, Elijah Kruger, Braden Krumholz, Maddie Leake, Lyneé Alves, Seraphina Loukas, Yatzari Lozano Vazquez, Haley Maki, Emily Martinez, Sierra Mckinney, Mykaela Tanino-Springsteen, Audrey Mitchell, Kipling Newman, Audrey Ng, Megan Lucyshyn, Andrew Nguyen, Stevie Ostman, Casandra Pearson, Alexandra Penney, Julia Gielczynski, Tyler Ball, Anna Rini, Christina Rorres, Simon Ruland, Helayna Schafer, Emma Sellers, Sarah Schuller, Claire Shaver, Kevin Summers, Isabella Shaw, Madison Sinar, Claudia Pena, Apshara Siwakoti, Carter Sorensen, Madi Sousa, Anna Sparling, Alexandra Revier, Brandon Thierry, Dylan Tyree, Maggie Williams, Lauren Wols

DU Undergraduate Research Journal Archive

DU Undergraduate Showcase: Research, Scholarship, and Creative Works


Head And Neck Tumor Histopathological Image Representation With Pre- Trained Convolutional Neural Network And Vision Transformer, Ranny Rahaningrum Herdiantoputri, Daisuke Komura, Tohru Ikeda, Shumpei Ishikawa Apr 2023

Head And Neck Tumor Histopathological Image Representation With Pre- Trained Convolutional Neural Network And Vision Transformer, Ranny Rahaningrum Herdiantoputri, Daisuke Komura, Tohru Ikeda, Shumpei Ishikawa

Journal of Dentistry Indonesia

Image representation via machine learning is an approach to quantitatively represent histopathological images of head and neck tumors for future applications of artificial intelligence-assisted pathological diagnosis systems. Objective: This study compares image representations produced by a pre-trained convolutional neural network (VGG16) to those produced by a vision transformer (ViT-L/14) in terms of the classification performance of head and neck tumors. Methods: W hole-slide images of five oral t umor categories (n = 319 cases) were analyzed. Image patches were created from manually annotated regions at 4096, 2048, and 1024 pixels and rescaled to 256 pixels. Image representations were …


Modeling Immune System Dynamics During Hiv Infection And Treatment With Differential Equations, Nicole Rychagov Apr 2023

Modeling Immune System Dynamics During Hiv Infection And Treatment With Differential Equations, Nicole Rychagov

CODEE Journal

An inquiry-based project that discusses immune system dynamics during HIV infection using differential equations is presented. The complex interactions between healthy T-cells, latently infected T-cells, actively infected T-cells, and the HIV virus are modeled using four nonlinear differential equations. The model is adapted to simulate long term HIV dynamics, including the AIDS state, and is used to simulate the long term effects of the traditional antiretroviral therapy (ART). The model is also used to test viral rebound over time of combined application of ART and a new drug that blocks the reactivation of the viral genome in the infected cells …


Hepatitis B And D: A Forecast On Actions Needed To Reduce Incidence And Achieve Elimination, Scott Greenhalgh, Andrew Klug May 2022

Hepatitis B And D: A Forecast On Actions Needed To Reduce Incidence And Achieve Elimination, Scott Greenhalgh, Andrew Klug

Spora: A Journal of Biomathematics

Viral hepatitis negatively affects the health of millions, with the worst health outcomes associated with the hepatitis D virus (HDV). Fortunately, HDV is rare and requires prior infection with the hepatitis B virus (HBV) before it can establish infection and transmit. Here, we develop a mathematical model of HBV and HDV transmission in Sub-Saharan Africa to investigate the effects of hepatitis B vaccination on both HBV and HDV. Our findings illustrate a hepatitis B vaccination rate above 0.006 year-1 reduces hepatitis D by over 90%, and a vaccination rate above 0.0221 year-1 reduces hepatitis B by over 90%, …


Toward Suicidal Ideation Detection With Lexical Network Features And Machine Learning, Ulya Bayram, William Lee, Daniel Santel, Ali Minai, Peggy Clark, Tracy Glauser, John Pestian Apr 2022

Toward Suicidal Ideation Detection With Lexical Network Features And Machine Learning, Ulya Bayram, William Lee, Daniel Santel, Ali Minai, Peggy Clark, Tracy Glauser, John Pestian

Northeast Journal of Complex Systems (NEJCS)

In this study, we introduce a new network feature for detecting suicidal ideation from clinical texts and conduct various additional experiments to enrich the state of knowledge. We evaluate statistical features with and without stopwords, use lexical networks for feature extraction and classification, and compare the results with standard machine learning methods using a logistic classifier, a neural network, and a deep learning method. We utilize three text collections. The first two contain transcriptions of interviews conducted by experts with suicidal (n=161 patients that experienced severe ideation) and control subjects (n=153). The third collection consists of interviews conducted by experts …


On Efficacy And Effectiveness Of Vaccines: A Mathematical Approach Based On Conditional Probability With Applications To The Covid-19 Context, Flavius Guias Mar 2022

On Efficacy And Effectiveness Of Vaccines: A Mathematical Approach Based On Conditional Probability With Applications To The Covid-19 Context, Flavius Guias

Spora: A Journal of Biomathematics

This paper presents a mathematically formalized approach which points out the relation between efficacy and effectiveness of vaccines. The first term denotes the relative degree of protection in clinical trials or under ideal conditions, while the latter is based on observed real-life data. We define the efficacy by a similar formula to the effectiveness, but the probabilities involved in the relative risk are conditional with respect to the exposure to the virus. If exposure and vaccination status are independent, the two quantities are equal. Otherwise, the observed value of the effectiveness is a biased one, as it could be seen …


(R1468) Global Analysis Of An Seirs Model For Covid-19 Capturing Saturated Incidence With Treatment Response, David A. Oluyori, Helen O. Adebayo, Ángel G.C. Pérez Dec 2021

(R1468) Global Analysis Of An Seirs Model For Covid-19 Capturing Saturated Incidence With Treatment Response, David A. Oluyori, Helen O. Adebayo, Ángel G.C. Pérez

Applications and Applied Mathematics: An International Journal (AAM)

In this work, a new SEIRS model with saturated incidence rate and piecewise linear treatment response is proposed to describe the dynamics of COVID-19. It is assumed that the treatment response is proportional to the number of infected people as long as the incidence cases are within the capacity of the healthcare system, after which the value becomes constant, when the number of confirmed cases exceeds the carrying capacity of the available medical facilities. Thus, the basic reproduction number of the model is obtained. It is proved that the disease-free equilibrium is globally asymptotically stable when the basic reproduction number …


(R1412) Stability And Bifurcation Of A Cholera Epidemic Model With Saturated Recovery Rate, Huda Abdul-Satar, Raid K. Naji Dec 2021

(R1412) Stability And Bifurcation Of A Cholera Epidemic Model With Saturated Recovery Rate, Huda Abdul-Satar, Raid K. Naji

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, a Cholera epidemic model is proposed and studied analytically as well as numerically. It is assumed that the disease is transmitted by contact with Vibrio cholerae and infected person according to dose-response function. However, the saturated treatment function is used to describe the recovery process. Moreover, the vaccine against the disease is assumed to be utterly ineffective. The existence, uniqueness and boundedness of the solution of the proposed model are discussed. All possible equilibrium points and the basic reproduction number are determined. The local stability and persistence conditions are established. Lyapunov method and the second additive compound …


Using Adaptive Research Design To Define The Proper Methodology To Use A Data Peek For Power: Step By Step Process, Tom Wasser Nov 2021

Using Adaptive Research Design To Define The Proper Methodology To Use A Data Peek For Power: Step By Step Process, Tom Wasser

Advances in Clinical Medical Research and Healthcare Delivery

When planning or conducting research in the hospital setting, often termed Real-World Environment (RWE), therapeutic assumptions and outcomes are often different than in the Randomized Clinical Trial (RCT) where medications, devices and therapies are tested and developed. This is because RWE research has a lack of experimental control, additional confounding due to patient complications and comorbid conditions, lack of pure patient selection and compliance with therapy in the patients being treated and many other factors as well. However, when RWE experiments are conducted, sample size determination using data from the RCT is common because that is the only data that …


Epidemic Conditions With Temporary Link Deactivation On A Network Sir Disease Model, Hannah Scanlon, John Gemmer Oct 2021

Epidemic Conditions With Temporary Link Deactivation On A Network Sir Disease Model, Hannah Scanlon, John Gemmer

Spora: A Journal of Biomathematics

The spread of an infectious disease depends on intrinsic properties of the disease as well as the connectivity and actions of the population. This study investigates the dynamics of an SIR type model which accounts for human tendency to avoid infection while also maintaining preexisting, interpersonal relationships. Specifically, we use a network model in which individuals probabilistically deactivate connections to infected individuals and later reconnect to the same individuals upon recovery. To analyze this network model, a mean field approximation consisting of a system of fourteen ordinary differential equations for the number of nodes and edges is developed. This system …