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A Mathematical Model For Managing Diphtheria Outbreaks In Nigeria Via Vaccination, Enhanced Surveillance, Effective Quarantine, And Social Distancing Measures, Hycienth Ortser Orapine, Nyiutya Cephas Ine, Dekera Jacob Washachi, Ali Audu Baidu, Lubem Matthew Kwaghkor Jun 2026

A Mathematical Model For Managing Diphtheria Outbreaks In Nigeria Via Vaccination, Enhanced Surveillance, Effective Quarantine, And Social Distancing Measures, Hycienth Ortser Orapine, Nyiutya Cephas Ine, Dekera Jacob Washachi, Ali Audu Baidu, Lubem Matthew Kwaghkor

Mathematical Modelling and Numerical Simulation with Applications

Diphtheria is a highly infectious respiratory and skin disease that poses a significant threat to global public health. In Nigeria, children and adults with low immunity remain at high risk due to recurring annual outbreaks in the last decade, with a death rate of as high as 68.8\%. This paper presents a deterministic compartmental model to evaluate the effectiveness of interventions implemented by the Nigerian government. The model's mathematical and epidemiological validity is established through proofs of non-negativity and boundedness. The basic reproduction number ($R_0$) is derived, and stability analysis confirms that the diphtheria-free equilibrium is locally and globally asymptotically …


Stochastic Analysis Of Epidemic Size And Peak Infection In An Svir Model With Imperfect Vaccine And External Source Of Infection, María Gamboa Pérez Jun 2026

Stochastic Analysis Of Epidemic Size And Peak Infection In An Svir Model With Imperfect Vaccine And External Source Of Infection, María Gamboa Pérez

Mathematical Modelling and Numerical Simulation with Applications

The dynamics of an infectious disease outbreak are studied under a stochastic framework in a closed population where individuals are homogeneously mixed. A vaccination program is implemented in the community prior to the start of the epidemic. The administered vaccine is imperfect, meaning that vaccinated individuals may still become infected upon contact with infected individuals. The mathematical Susceptible-Vaccinated-Infected-Recovered (SVIR) model describing the evolution of the epidemic is formulated as an absorbing, continuous-time, three-dimensional Markov chain with compartments for vaccinated, susceptible, infected and recovered individuals. The aim of this study is to characterize two fundamental epidemiological quantities: the maximum number of …


Dynamical Behavior, Extinction And Persistence In A Stochastic Delayed Two-Strain Epidemic Model With A Generalized Crowley-Martin Incidence Rate, Amina Allali, Dounia Bentaleb, Saida Amine Jun 2026

Dynamical Behavior, Extinction And Persistence In A Stochastic Delayed Two-Strain Epidemic Model With A Generalized Crowley-Martin Incidence Rate, Amina Allali, Dounia Bentaleb, Saida Amine

Mathematical Modelling and Numerical Simulation with Applications

This paper develops and analyzes a novel delayed stochastic SIR epidemic model with two interacting strains and general incidence functions. By establishing the existence and uniqueness of a positive global solution, the well-posedness of the model under stochastic perturbations is ensured. Extinction occurs when the stochastic reproduction number falls below unity, as demonstrated through Itô calculus and martingale convergence theorems, while persistence is guaranteed under the Crowley–Martin incidence when it exceeds one. Numerical experiments based on the Positive Preserving Truncated Euler–Maruyama (PPTEM) scheme confirm the analytical predictions and highlight the influence of time delay and noise intensity on the long-term …


Tumor–Immune Dynamics With Memory And Time Delay: A Fractional-Order Model With Ctla-4 Regulation, Mutaz Mohammad, Mohyeedden Sweidan, Alexander Trounev, Fathalla Rihan Jun 2026

Tumor–Immune Dynamics With Memory And Time Delay: A Fractional-Order Model With Ctla-4 Regulation, Mutaz Mohammad, Mohyeedden Sweidan, Alexander Trounev, Fathalla Rihan

Mathematical Modelling and Numerical Simulation with Applications

This study develops a fractional-order tumor-immune interaction model incorporating Caputo memory effects, delayed immune activation, and CTLA-4 checkpoint regulation. The model describes the coupled dynamics of tumor cells, CD4$^{+}$ T cells, IFN-$\gamma$, and CTLA-4, and extends classical integer-order tumor-immune models by accounting for hereditary immune responses and biologically motivated latency effects. Theoretical properties, including positivity, boundedness, equilibrium structure, and fractional-order stability, are examined to establish the biological and mathematical consistency of the model. The delayed fractional system is then investigated computationally by comparing several numerical methods, including finite difference discretization, Daubechies wavelet collocation, Euler wavelet collocation, and a predictor-corrector scheme. …


Interval-Valued Neutrosophic Dombi Bonferroni Mean Aggregation Operators In Medical Diagnosis And Sustainable Energy, Maryam Faisal, Muhammad Nadeem, Muhammad Kamran Jun 2026

Interval-Valued Neutrosophic Dombi Bonferroni Mean Aggregation Operators In Medical Diagnosis And Sustainable Energy, Maryam Faisal, Muhammad Nadeem, Muhammad Kamran

Neutrosophic Systems with Applications

Medical diagnosis is one of the most difficult fields in which decisions must be made due to the fact that medical information often has characteristics of uncertainty, incompleteness, imprecision and even contradiction. Traditional aggregation and decision-making methods are often not well suited to such complexities, and may result in less reliable diagnostic outcomes. In order to overcome these drawbacks, the authors propose a new approach using a novel representation of Interval-Valued Neutrosophic Sets (IVNSs), the Dombi operational laws, and Bonferroni Mean (BM) aggregation operators. The proposed framework is specifically aimed at coping with uncertainty, indeterminacy and falsity all at once …


Re: Conditional Approval Letter For Diggings East 100% Remedial Design Package Submittal (Dated May 29, 2006), Emma Rott Jun 2026

Re: Conditional Approval Letter For Diggings East 100% Remedial Design Package Submittal (Dated May 29, 2006), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Re: Conditional Approval Letter For The Final Silver Bow Creek Conservation Area Materials Management Plan (Dated May 28, 2026), Emma Rott Jun 2026

Re: Conditional Approval Letter For The Final Silver Bow Creek Conservation Area Materials Management Plan (Dated May 28, 2026), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Natural Radioactivity And Radiological Hazards In Sediments From The Lindi Coast, Indian Ocean, Tanzania, Viator Mujuni, Innocent J. Lugendo Jun 2026

Natural Radioactivity And Radiological Hazards In Sediments From The Lindi Coast, Indian Ocean, Tanzania, Viator Mujuni, Innocent J. Lugendo

Tanzania Journal of Science

The Lindi coast of the Indian Ocean, located in southeastern Tanzania, supports rich biodiversity and has recently experienced rapid growth in socio-economic activities such as fishing, mining, and oil and gas exploration. These activities may enhance levels of natural radioactivity in coastal sediments, potentially increasing radiation exposure to local populations. Therefore, monitoring radioactivity levels and estimating associated radiation doses in this region is important. In this study, thirty-six sediment samples were collected from twelve locations along the Lindi coast and analysed for naturally occurring radionuclides using high-purity germanium (HPGe) gamma-ray spectrometry. The activity concentrations of 226Ra, 232Th, and …


Hydrogeochemical Characterization Of Groundwater In Fractured Crystalline Basement Aquifers In Dodoma, Central Tanzania: Implications On Water Quality For Domestic And Irrigation Applications, George J. Ishabairu, Simon R. Melchioly, Charles H. Kasanzu, Gabriel D. Mulibo Jun 2026

Hydrogeochemical Characterization Of Groundwater In Fractured Crystalline Basement Aquifers In Dodoma, Central Tanzania: Implications On Water Quality For Domestic And Irrigation Applications, George J. Ishabairu, Simon R. Melchioly, Charles H. Kasanzu, Gabriel D. Mulibo

Tanzania Journal of Science

Assessment of groundwater hydrogeochemistry characteristics of aquifers plays a vital role in establishing water quality status and its suitability for human and industrial use. The main objective of this research was to carry out hydrogeochemical characterization of groundwater and assess its impacts on water quality and spatial variability of groundwater geochemistry in Dodoma, Tanzania. The methods used include groundwater sampling, laboratory analysis to determine physico- chemical parameters and data processing to classify the groundwater hydrochemical facies. The results show that the average value for pH is 7.2, for electrical conductivity (EC) is 1108 µS/cm and for total dissolved solids (TDS) …


Tumor-Immune Dynamics With Memory And Time Delay: A Fractional-Order Model With Ctla-4 Regulation, Mutaz Mohammad, Mohyeedden Sweidan, Alexander Trounev, Fathalla Rihan Jun 2026

Tumor-Immune Dynamics With Memory And Time Delay: A Fractional-Order Model With Ctla-4 Regulation, Mutaz Mohammad, Mohyeedden Sweidan, Alexander Trounev, Fathalla Rihan

All Works

This study develops a fractional-order tumor-immune interaction model incorporating Caputo memory effects, delayed immune activation, and CTLA-4 checkpoint regulation. The model describes the coupled dynamics of tumor cells, CD4^+ T cells, IFN-γ, and CTLA-4, and extends classical integer-order tumor-immune models by accounting for hereditary immune responses and biologically motivated latency effects. Theoretical properties, including positivity, boundedness, equilibrium structure, and fractional-order stability, are examined to establish the biological and mathematical consistency of the model. The delayed fractional system is then investigated computationally by comparing several numerical methods, including finite difference discretization, Daubechies wavelet collocation, Euler wavelet collocation, and a predictor-corrector scheme. …


Re: Conditional Approval Letter For The Final Revised Silver Bow Creek Conservation Area (Sbcca) Construction Quality Assurance Plan (Cqap) (Dated May 28, 2026) And The Final Silver Bow Creek Conservation Area (Sbcca) Construction Monitoring Quality Assurance Project Plan (Qapp) (Dated May 28, 2026), Emma Rott Jun 2026

Re: Conditional Approval Letter For The Final Revised Silver Bow Creek Conservation Area (Sbcca) Construction Quality Assurance Plan (Cqap) (Dated May 28, 2026) And The Final Silver Bow Creek Conservation Area (Sbcca) Construction Monitoring Quality Assurance Project Plan (Qapp) (Dated May 28, 2026), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Re: Conditional Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Silver Bow Creek Conservation Area (Sbcca) Operations And Maintenance (O&M) Plan (Dated May 29, 2006), Emma Rott Jun 2026

Re: Conditional Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Silver Bow Creek Conservation Area (Sbcca) Operations And Maintenance (O&M) Plan (Dated May 29, 2006), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Third Butte Rmap Biomonitoring (Phase 3) Report, Ramboll, Atlantic Richfield Company Jun 2026

Third Butte Rmap Biomonitoring (Phase 3) Report, Ramboll, Atlantic Richfield Company

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Forecasting Covid-19 New Cases Using Nbeats Deep Learning And Mobility Data, Amril Nazir, Mohammad Shorfuzzaman, Muhammad Lujaini Lotfi, Firuz Kamalov, Sufian Badawi, Maen Takruri, Abdul Halim Jallad Jun 2026

Forecasting Covid-19 New Cases Using Nbeats Deep Learning And Mobility Data, Amril Nazir, Mohammad Shorfuzzaman, Muhammad Lujaini Lotfi, Firuz Kamalov, Sufian Badawi, Maen Takruri, Abdul Halim Jallad

All Works

COVID-19 is a highly contagious disease transmitted primarily through human contact. Therefore, understanding population mobility is essential for predicting COVID-19 case trends. In this paper, we propose a novel deep learning approach for forecasting new COVID-19 cases using a neural architecture called Neural Basis Expansion Analysis for Interpretable Time Series (N-BEATS). The N-BEATS model effectively handles long input sequences and large output horizons without information loss or increased computational complexity. We compare the performance of N-BEATS with a state-of-the-art benchmark model, LSTM-Markov, across four major countries: the United States, the United Kingdom, Russia, and Brazil. Three distinct COVID-19 datasets from …


Research On Dic Monitoring Of Dynamic Deflection And Damage Identification Method For Small And Medium-Span Bridges, Wang Yong, Li Derui, Tang Haotian, Yan Xingfei, Cheng Bin Jun 2026

Research On Dic Monitoring Of Dynamic Deflection And Damage Identification Method For Small And Medium-Span Bridges, Wang Yong, Li Derui, Tang Haotian, Yan Xingfei, Cheng Bin

Journal of China & Foreign Highway

A large number of built small and medium-span bridges in China are facing the problem of increasingly degrading structural performance. Therefore, it is of great significance to carry out lightweight intelligent monitoring and realize damage identification and early warning, so as to ensure the safe operation of these bridges. For typical small and medium-span simply supported beam bridges, a damage analysis method based on measured dynamic deflection data was established by combining the influence line theory and mechanical constitutive equations. Furthermore, based on the high-precision monitoring algorithm and instruments of digital image correlation (DIC), the real-time dynamic deflection data of …


Teachers’ Awareness Of Family Engagement In Multilingual Education, Sedighe Zamani Roodsari Jun 2026

Teachers’ Awareness Of Family Engagement In Multilingual Education, Sedighe Zamani Roodsari

Journal of Multicultural Affairs

This study investigated public school teachers’ awareness of family engagement as a linguistic and cultural resource for multilingual students. Multilinguals are typically described as individuals who can communicate in more than one language, with English not being their native language, and their linguistic choices are influenced by societal norms and systems (Šifrar Kalan et al., 2024; Wei, 2008). Preparing pre-service teachers to enhance opportunities for multilingual students remains a critical need in teacher education programs, as they strive to move beyond monolingual ideologies in their teaching practices (Cárdenas Curiel et al., 2024; Kim & Choi, 2020; Williams & Ewing, 2019). …


Examining Nitrate Concentrations In Rainwater In The Marine Boundary Layer In St. Petersburg, Sam Irvine, Anson Kirsch, Ben Lloyd '25, Yasin Elshorbany, James Ivey Jun 2026

Examining Nitrate Concentrations In Rainwater In The Marine Boundary Layer In St. Petersburg, Sam Irvine, Anson Kirsch, Ben Lloyd '25, Yasin Elshorbany, James Ivey

Student Research

Harmful algae blooms (HABs) are a common, natural phenomenon that occur in bodies of water. Karenia brevis is an algae species where, in excess, it can result in red tide events which deplete nutrients in the area, impacting aquatic life and releasing toxic gasses. Past research shows that K. brevis can grow through nutrient absorption in response to excess nitrate in water. This project sought to examine whether nitrates from rainfall are responsible for creating an increase in nitrogen concentrations in the water surrounding St. Petersburg which can lead to algae bloom growth. Results showed that rainwater has higher concentrations …


Using Low-Frequency Vibrational Spectroscopy To Develop Analytical Profiles For Polymorphic Organic Molecular Crystals, Salvatore Zarrella Jun 2026

Using Low-Frequency Vibrational Spectroscopy To Develop Analytical Profiles For Polymorphic Organic Molecular Crystals, Salvatore Zarrella

Dissertations - ALL

Low-frequency vibrational spectroscopy provides a sensitive approach for characterizing polymorphism and intermolecular dynamics in organic molecular crystals. Terahertz time-domain spectroscopy (THz-TDS) and low-frequency Raman spectroscopy probe collective lattice vibrations arising from weak intermolecular interactions, offering direct insight into crystal packing, phase stability, and structural organization that is often inaccessible to conventional diffraction and mid-infrared techniques. To interpret these modes, experimental measurements are combined with periodic solid-state density functional theory (ss-DFT), which enables vibrational assignments to specific intermolecular motions, and crystal structure prediction (CSP), which maps accessible polymorphic energy landscapes. Together, these methods form a unified experimental–computational framework for understanding molecular …


(R2077) Enhancing Queue Management: Dynamic Server Allocation And Optional Services In Stochastic Modeling, G. Ayyappan, S. Sankeetha Jun 2026

(R2077) Enhancing Queue Management: Dynamic Server Allocation And Optional Services In Stochastic Modeling, G. Ayyappan, S. Sankeetha

Applications and Applied Mathematics: An International Journal (AAM)

Consider a queueing system with a single server, where customer arrivals follow a Markovian arrival process and service times follow a phase-type distribution. The main server has the capability to recruit an additional server when the number of customers in the system exceeds a certain threshold, denoted as L. Both servers provide normal service to customers, and optional service is provided upon request. The main server takes multiple vacations, with the durations following an exponential distribution with rate parameter η, until there is at least one customer in the system. This system can be represented as a Markov chain process, …


(R2174) A Stationary First-Order Autoregressive Process With New Discrete Lindley Marginal Distribution, Tégawendé Martin Kabore, Jean-Etienne Ouindllassida Ouédraogo Jun 2026

(R2174) A Stationary First-Order Autoregressive Process With New Discrete Lindley Marginal Distribution, Tégawendé Martin Kabore, Jean-Etienne Ouindllassida Ouédraogo

Applications and Applied Mathematics: An International Journal (AAM)

This paper introduces a new stationary first-order autoregressive integer-valued process with a marginal distribution following the New Discrete Lindley distribution, referred to as NDLINAR( 1). The process is developed to model over-dispersed count time series exhibiting a mixed behavior arising from the combination of multiple distributions. Its statistical properties are thoroughly investigated, and the parameters are estimated using conditional maximum likelihood. The asymptotic properties of the estimators are also analyzed. The performance of the proposed model is evaluated by comparing it with other existing INAR(1) processes through applications to real datasets. Results demonstrate that the NDL-INAR(1) process effectively captures the …


(R2167) Global Stability Of Seirs Model With Single Dose Vaccination In Varying Population, Govind Jha, Prabhat Mandal, Sarita Jha Jun 2026

(R2167) Global Stability Of Seirs Model With Single Dose Vaccination In Varying Population, Govind Jha, Prabhat Mandal, Sarita Jha

Applications and Applied Mathematics: An International Journal (AAM)

Understanding the evolution of infectious diseases within a dynamic population is essential for formulating effective public health strategies. This work introduces an enhanced SEIRS epidemic model that incorporates demographic variation and a single-dose vaccination strategy, supporting that immunity can be reduced over time. The model reflects diseases in which individuals may return to the susceptible state after recovery. Extending prior reduced three-dimensional models, this study develops a complete four-dimensional SEIRS framework, thereby increasing the model’s applicability to real-world scenarios. The inclusion of the full system presents greater analytical challenges. To overcome this, we extend the second additive compound matrix and …


(R2185) Operations On Bipolar Complex Neutrosophic Matrices And Its Application In Un’S Sdg-14 & Sdg-3 Using Python, N. Krishnapraveen, T. Muthuraji Jun 2026

(R2185) Operations On Bipolar Complex Neutrosophic Matrices And Its Application In Un’S Sdg-14 & Sdg-3 Using Python, N. Krishnapraveen, T. Muthuraji

Applications and Applied Mathematics: An International Journal (AAM)

Decision-making in sustainability oriented environments frequently involves bipolar evaluations, indeterminate information and phase dependent uncertainty that cannot be adequately represented by existing neutrosophic matrix models. To address this limitation, this study introduces a Bipolar Complex Neutrosophic Matrix (BCNM) framework that integrates bipolar semantics with complex valued uncertainty in a coherent algebraic structure. Fundamental operations and structural properties are rigorously established to ensure mathematical consistency. To facilitate practical multi criteria decision analysis (MCDA), novel score, accuracy, and hybrid aggregation operators are developed. The computational feasibility of the proposed approach is analyzed, demonstrating linear complexity with respect to the number of alternatives …


(R2161) Robust Optimization Of Industrial Hazardous Waste Location-Routing Problem Considering Response Actions To Environmental Risk, Sharareh Teimoori, Farhad Hosseinzadeh Lotfi, Seyyed Esmaeil Najafi, Navid Rafiei Jun 2026

(R2161) Robust Optimization Of Industrial Hazardous Waste Location-Routing Problem Considering Response Actions To Environmental Risk, Sharareh Teimoori, Farhad Hosseinzadeh Lotfi, Seyyed Esmaeil Najafi, Navid Rafiei

Applications and Applied Mathematics: An International Journal (AAM)

The management of hazardous industrial waste has emerged as a significant global challenge due to rapid technological advancements. Industrial hazardous waste management systems must be designed not only to be cost-effective but also to minimize environmental risks. This study proposes a mixed-integer programming model for the location-routing of industrial hazardous waste that incorporates both primary and secondary environmental risks, along with suitable response actions. Furthermore, a scenario-based robust optimization model is developed to address uncertainties in the quantities of industrial hazardous waste. A case study is conducted to demonstrate the applicability and comparative performance of the nominal and robust models. …


Peptide And Peptide Bioconjugate Based Drug Development For The Treatment Of Metabolic Diseases, Nancy Cham Jun 2026

Peptide And Peptide Bioconjugate Based Drug Development For The Treatment Of Metabolic Diseases, Nancy Cham

Dissertations - ALL

The Doyle group has coined the term ‘corrination’ to describe the conjugate modification of a peptide, protein, small molecule, or radionuclide with a corrin ring-containing molecule such as cobalamin, also known as vitamin B12 (B12), or cobinamides. By exploiting the innate chemico-physical properties of corrin ring-containing compounds, both in general and specifically via the innate dietary B12 uptake pathway in mammals, corrination has been explored for drug development and targeted/localized delivery of probes and therapeutics. Most recently, it is in the field of peptide-based therapeutics that corrination is generating significant interest, no doubt driven in part by the recent successes …


Molecular Identification Of Cryptococcus Albidus Isolated From A Gingivitis Infection In A Male From Karbala City, Iraq, Maysaa Taqi Al-Khazali, Zahraa Raheem Murshidy, Sarah Kadhim Al-Rahimy, Sura Abd Ali Kadhim Mohammed, Dhuha Ali Hussein Jun 2026

Molecular Identification Of Cryptococcus Albidus Isolated From A Gingivitis Infection In A Male From Karbala City, Iraq, Maysaa Taqi Al-Khazali, Zahraa Raheem Murshidy, Sarah Kadhim Al-Rahimy, Sura Abd Ali Kadhim Mohammed, Dhuha Ali Hussein

Karbala International Journal of Modern Science

The current study presents a case of gingivitis caused by Cryptococcus albidus in a 35-year-old male from the city of Karbala in Iraq. This fungal species was identified via morphology, microscopy, additionally to the VITEK system. C. albidus was further confirmed using the polymerase chain reaction (PCR) technique by amplifying the 18S rRNA gene as a universal primer and sequencing. Sequences analysis revealed that this strain of C. albidus had not been previously documented in the NCBI database. Hence, the newly obtained sequences were submitted to the GenBank repository and assigned the accession number OQ975882.1, marking the first report of …


Instructions To Authors, Academy Editors Jun 2026

Instructions To Authors, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


Journal Acknowledgements And Editorial Board, Academy Editors Jun 2026

Journal Acknowledgements And Editorial Board, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


Keynote Address And Meeting Program, Academy Editors Jun 2026

Keynote Address And Meeting Program, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


Business Meeting Report (Secretary's And Treasurer's Report), Academy Editors Jun 2026

Business Meeting Report (Secretary's And Treasurer's Report), Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


Artificial Food Colors Are Not Needed To Attract Ruby-Throated Hummingbirds (Archilochus Colubris) To Feeders, A. Siddiqui, R. Kannan Jun 2026

Artificial Food Colors Are Not Needed To Attract Ruby-Throated Hummingbirds (Archilochus Colubris) To Feeders, A. Siddiqui, R. Kannan

Journal of the Arkansas Academy of Science

No abstract provided.