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Connectome Specific Harmonic Wave Analysis Of Disordered Brain States, Stephen A. Odunsi, Ihsan Salloum Sep 2023

Connectome Specific Harmonic Wave Analysis Of Disordered Brain States, Stephen A. Odunsi, Ihsan Salloum

Research Symposium

Background: Connectome Harmonics analysis is a novel neuroimaging framework that defines brain states as neural spatial patterns associated with different frequencies emerging within a brain. Frequencies corresponding to specific brain states, or connectome-specific harmonic waves (CSHWs), are estimated to be the building blocks of brain activity, linking cortical oscillations, functional connectivity, and structural connectivity. Using this framework, studies will examine CSHWs of patients to catalog and analyze the spatiotemporal neural dynamics of patients with disordered brain states.

Methods: By using MRI (or fMRI) and DTI data extracted from MRI scans of patients, cortical surface anatomy and the underlying neural tracts …


An Ngqd Based Diagnostic Tool For Pancreatic Cancer, Ryan Ketan Ajgaonkar, Bong Lee, Alina Valimukhametova, Anton Naumov, Giridhar Akkaraju Sep 2023

An Ngqd Based Diagnostic Tool For Pancreatic Cancer, Ryan Ketan Ajgaonkar, Bong Lee, Alina Valimukhametova, Anton Naumov, Giridhar Akkaraju

Research Symposium

Background: Pancreatic cancer remains difficult to detect at early stages which contributes to a poor five-yearsurvival rate. Therefore, early detection approaches based on novel technologies should be explored to address this critical health issue. Nanomaterials have recently emerged as frontrunners for diagnostic applications due to their small size in the 1-100 nm range, which facilitates one-on-one interactions with a variety of biomolecules like oligonucleotides and makes them suitable for a plethora of detection and delivery applications. In this work, the presence of specific pancreatic cancer miRNA (pre-miR-132) is detected utilizing the fluorescence properties of highly biocompatible nitrogen-doped graphene quantum dots …


Search For Gravitational Waves Associated With Fast Radio Bursts Detected By Chime/Frb During The Ligo–Virgo Observing Run O3a, R. Abbott, T. Abbott, F. Acernese, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Volker Quetschke, Wenhui Wang Sep 2023

Search For Gravitational Waves Associated With Fast Radio Bursts Detected By Chime/Frb During The Ligo–Virgo Observing Run O3a, R. Abbott, T. Abbott, F. Acernese, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Volker Quetschke, Wenhui Wang

Physics & Astronomy Faculty Publications

We search for gravitational-wave (GW) transients associated with fast radio bursts (FRBs) detected by the Canadian Hydrogen Intensity Mapping Experiment Fast Radio Burst Project, during the first part of the third observing run of Advanced LIGO and Advanced Virgo (2019 April 1 15:00 UTC–2019 October 1 15:00 UTC). Triggers from 22 FRBs were analyzed with a search that targets both binary neutron star (BNS) and neutron star–black hole (NSBH) mergers. A targeted search for generic GW transients was conducted on 40 FRBs. We find no significant evidence for a GW association in either search. Given the large uncertainties in the …


Effects Of Spin-Orbit Coupling On Gravitational Waveforms From A Triaxial Nonaligned Neutron Star In A Binary System, Wen-Fan Feng, Tan Liu, Jie-Wen Che, Yan Wang, Soumya D. Mohanty Sep 2023

Effects Of Spin-Orbit Coupling On Gravitational Waveforms From A Triaxial Nonaligned Neutron Star In A Binary System, Wen-Fan Feng, Tan Liu, Jie-Wen Che, Yan Wang, Soumya D. Mohanty

Physics & Astronomy Faculty Publications

Spinning neutron stars (NSs) can emit continuous gravitational waves (GWs) that carry a wealth of information about the compact object. If such a signal is detected, it will provide us with new insight into the physical properties of matter under extreme conditions. According to binary population synthesis simulations, future space-based GW detectors, such as LISA and TianQin, can potentially detect some double NSs in tight binaries with orbital periods shorter than 10 minutes. The possibility of a successful directed search for continuous GWs from the spinning NS in such a binary system identified by LISA/TianQin will be significantly increased with …


Modeling Nonsegmented Negative-Strand Rna Virus (Nnsv) Transcription With Ejective Polymerase Collisions And Biased Diffusion, Felipe-Andres Piedra Sep 2023

Modeling Nonsegmented Negative-Strand Rna Virus (Nnsv) Transcription With Ejective Polymerase Collisions And Biased Diffusion, Felipe-Andres Piedra

Research Symposium

Background: The textbook model of NNSV transcription predicts a gene expression gradient. However, multiple studies show non-gradient gene expression patterns or data inconsistent with a simple gradient. Regarding the latter, several studies show a dramatic decrease in gene expression over the last two genes of the respiratory syncytial virus (RSV) genome (a highly studied NNSV). The textbook model cannot explain these phenomena.

Methods: Computational models of RSV and vesicular stomatitis virus (VSV – another highly studied NNSV) transcription were written in the Python programming language using the Scientific Python Development Environment. The model code is freely available on GitHub: …


Using Cartesian Coordinate Systems To Create, Classify, And Retrieve Biomedical Time-Series: Applications To 24-Hour Ambulatory Blood Pressure Monitoring, Antonio Garcia, Gladys E. Maestre, John Blangero, Jesus D. Melgarejo, Julio Facelli Sep 2023

Using Cartesian Coordinate Systems To Create, Classify, And Retrieve Biomedical Time-Series: Applications To 24-Hour Ambulatory Blood Pressure Monitoring, Antonio Garcia, Gladys E. Maestre, John Blangero, Jesus D. Melgarejo, Julio Facelli

Research Symposium

Background: Ambulatory Blood Pressure Measurement (ABPM) allows physicians to monitor blood pressure variability under everyday living conditions and predicts clinical outcomes better than conventional blood-pressure measurement. ABPM can demonstrate mean arterial pressure (MAP) behavior over 24 hours relevant to clinical practice, such as nocturnal hypertension or increased blood pressure variability. We hypothesized that individuals with the same cardiovascular health status would have the same MAP signal (MAPs) waveform.

Methods: This study reutilizes a data subset from the IDACO Consortium to create 24-hour MAPs. We assigned all the MAPs to data matrix X, performed principal components analysis (PCA) to X, and …


Self-Organization For Community Resilience In An Invisible Agricultural Community, Anna Erwin, Chelsea A. Silva, Zhao Ma Sep 2023

Self-Organization For Community Resilience In An Invisible Agricultural Community, Anna Erwin, Chelsea A. Silva, Zhao Ma

School of Earth, Environmental, & Marine Sciences Faculty Publications

This study investigates how self-organizing efforts by residents of informal settlements, primarily migrant and informal farmworkers, shape community resilience in Majes, a water-scarce irrigation district in the Atacama Desert of Peru. We collected 45 semi-structured interviews with residents and authorities in Majes and analyzed findings through a framework of self-organizing. Analyses revealed that self-organizing by residents of informal settlements incorporated the three components of White’s theory of Community Agency and Community Resilience, which contends that marginalized communities increase resilience by fostering a commons praxis, practicing a prefigurative politics, and developing opportunities for economic autonomy. We also found …


Neighboring Mapping Points Theorem, Andrei V. Malyutin, Oleg R. Musin Sep 2023

Neighboring Mapping Points Theorem, Andrei V. Malyutin, Oleg R. Musin

School of Mathematical & Statistical Sciences Faculty Publications

We introduce and study a new family of theorems extending the class of Borsuk–Ulam and topological Radon type theorems. The defining idea for this new family is to replace requirements of the form “the image of a subset that is large in some sense is a singleton” with requirements of the milder form “the image of a subset that is large in some sense is a subset that is small in some sense”. This approach covers the case of mappings Sm→Rn with m

An example of a statement from this new family is the following theorem. Let f be a …


Study Of Multilayer Flow Of Two Immiscible Nanofluids In A Duct With Viscous Dissipation, Jawali C. Umavathi, Mahanthesh Basavarajappa Sep 2023

Study Of Multilayer Flow Of Two Immiscible Nanofluids In A Duct With Viscous Dissipation, Jawali C. Umavathi, Mahanthesh Basavarajappa

School of Mathematical & Statistical Sciences Faculty Publications

Numerical simulations for the mixed convective multilayer flow of two different immiscible nanofluids in a duct with viscous heating effects were performed in this study. The left and right faces of the duct are maintained to be isothermal, while other side faces are insulated. The mathematical governing system for each layer consists of an incompressibility condition equation, the Navier–Stokes momentum equation, and the conservation of energy equation. At the interface of the immiscible layer, the continuity of velocity, shear stress, temperature, and heat flux are considered. The dimensionless equations governing each layer were numerically integrated using the finite difference method …


The Rider (2023-09-25), Natalie Lapsley Sep 2023

The Rider (2023-09-25), Natalie Lapsley

The Rider Archives

Vol.9 No.5


Investigation Of The Thermodynamics For The Removal Of As(Iii) And As(V) From Water Using Synthesized Zno Nanoparticles And The Effects Of Ph, Temperature, And Time, Helia M. Morales Ramirez, Grecia Torreblanca, Arnulfo Mar, Mataz Alcoutlabi, Thomas Eubanks, Erik Plata, Jason Parsons Sep 2023

Investigation Of The Thermodynamics For The Removal Of As(Iii) And As(V) From Water Using Synthesized Zno Nanoparticles And The Effects Of Ph, Temperature, And Time, Helia M. Morales Ramirez, Grecia Torreblanca, Arnulfo Mar, Mataz Alcoutlabi, Thomas Eubanks, Erik Plata, Jason Parsons

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

In the present study, the removal of both As(III) and As(V) from aqueous solutions using synthesized ZnO nanomaterials was achieved. The ZnO nanomaterial was synthesized using a precipitation technique and characterized using XRD, SEM, and Raman spectroscopy. XRD confirmed the ZnO nanoparticles were present in the hexagonal wurtzite structure. SEM of the particles showed they were aggregates of triangular and spherical particles. The average nanoparticle size was determined to be 62.03 ± 4.06 nm using Scherrer’s analysis of the three largest diffraction peaks. Raman spectroscopy of the ZnO nanoparticles showed only ZnO peaks, whereas the after-reaction samples indicated that As(V) …


Microplastics Distribution Within Western Arctic Seawater And Sea Ice, Alessandra D’Angelo, Nicole Trenholm, Brice Loose, Laura Glastra, Jacob Strock, Jongsun Kim Sep 2023

Microplastics Distribution Within Western Arctic Seawater And Sea Ice, Alessandra D’Angelo, Nicole Trenholm, Brice Loose, Laura Glastra, Jacob Strock, Jongsun Kim

School of Earth, Environmental, & Marine Sciences Faculty Publications

Microplastic pollution has emerged as a global environmental concern, exhibiting wide distribution within marine ecosystems, including the Arctic Ocean. Limited Arctic microplastic data exist from beached plastics, seabed sediments, floating plastics, and sea ice. However, no studies have examined microplastics in the sea ice of the Canadian Arctic Archipelago and Tallurutiup Imanga National Marine Conservation Area, and few have explored Arctic marginal seas’ water column. The majority of the microplastic data originates from the Eurasian Arctic, with limited data available from other regions of the Arctic Ocean. This study presents data from two distinct campaigns in the Canadian Arctic Archipelago …


Draft Genome Of Methanol-Oxidizing Methylobacterium Fujisawaense Strain Lac1, Jooho Chung, Jinha Kim, John C. Blazier, Myung Hwangbo, Kung-Hui Chu Sep 2023

Draft Genome Of Methanol-Oxidizing Methylobacterium Fujisawaense Strain Lac1, Jooho Chung, Jinha Kim, John C. Blazier, Myung Hwangbo, Kung-Hui Chu

School of Earth, Environmental, & Marine Sciences Faculty Publications

We report the draft genome of Methylobacterium fujisawaense LAC1 isolated from an acidic aquifer in Indian Head, MD, USA. The genome contains 5,883,000 bp and has a GC content of 70% with 5,434 protein-encoding genes with functional assignments. This strain can grow on methanol with lanthanum, a rare earth element.


The Rider (2023-09-18), Natalie Lapsley Sep 2023

The Rider (2023-09-18), Natalie Lapsley

The Rider Archives

Vol.9 No.4


The Rider (2023-09-11), Natalie Lapsley Sep 2023

The Rider (2023-09-11), Natalie Lapsley

The Rider Archives

Vol.9 No.3


Powerful Radio Sources In The Southern Sky. Ii. A Swift X-Ray Perspective, Francesco Massaro, S. V. White, A. Paggi, A. Jimenez-Gallardo, Juan P. Madrid, C. Mazzucchelli, W. R. Forman, A. Capetti, C. C. Cheung Sep 2023

Powerful Radio Sources In The Southern Sky. Ii. A Swift X-Ray Perspective, Francesco Massaro, S. V. White, A. Paggi, A. Jimenez-Gallardo, Juan P. Madrid, C. Mazzucchelli, W. R. Forman, A. Capetti, C. C. Cheung

Physics & Astronomy Faculty Publications

We recently constructed the G4Jy-3CRE, a catalog of extragalactic radio sources based on the GLEAM 4-Jy (G4Jy) sample, with the aim of increasing the number of powerful radio galaxies and quasars with similar selection criteria to those of the revised release of the Third Cambridge Catalog (3CR). The G4Jy-3CRE consists of a total of 264 radio sources mainly visible from the Southern Hemisphere. Here, we present an initial X-ray analysis of 89 G4Jy-3CRE radio sources with archival X-ray observations from the Neil Gehrels Swift Observatory. We reduced a total of 624 Swift observations, for about 0.9 Ms of integrated exposure …


Exploring The Capabilities Of Gibbs Sampling In Pulsar Timing Arrays, Nima Laal, William G. Lamb, Joseph D. Romano, Xavier Siemens, Stephen R. Taylor, Rutger Van Haasteren Sep 2023

Exploring The Capabilities Of Gibbs Sampling In Pulsar Timing Arrays, Nima Laal, William G. Lamb, Joseph D. Romano, Xavier Siemens, Stephen R. Taylor, Rutger Van Haasteren

Physics & Astronomy Faculty Publications

We explore the use of Gibbs sampling in estimating the noise properties of individual pulsars and illustrate its effectiveness using the NANOGrav 11-year dataset. We find that Gibbs sampling noise modeling (GM) is more efficient than the current standard Bayesian techniques (SM) for single pulsar analyses by yielding model parameter posteriors with average effective-sample-size ratio (GM/SM) of 6 across all parameters and pulsars. Furthermore, the output of GM contains posteriors for the Fourier coefficients that can be used to characterize the underlying red noise process of any pulsar’s timing residuals, which are absent in current implementations of SM. Through simulations, …


Multi-Symplectic Simulation On Soliton-Collision For Nonlinear Perturbed Schrödinger Equation, Peijun Zhang, Weipeng Hu, Zhen Wang, Zhijun Qiao Sep 2023

Multi-Symplectic Simulation On Soliton-Collision For Nonlinear Perturbed Schrödinger Equation, Peijun Zhang, Weipeng Hu, Zhen Wang, Zhijun Qiao

School of Mathematical & Statistical Sciences Faculty Publications

Seeking solitary wave solutions and revealing their interactional characteristics for nonlinear evolution equations help us lot to comprehend the motion laws of the microparticles. As a local nonlinear dynamic behavior, the soliton-collision is difficult to be reproduced numerically. In this paper, the soliton-collision process in the nonlinear perturbed Schrödinger equation is simulated employing the multi-symplectic method. The multi-symplectic formulations are derived including the multi-symplectic form and three local conservation laws of the nonlinear perturbed Schrödinger equation. Employing the implicit midpoint rule, we construct a multi-symplectic scheme, which is equivalent to the Preissmann box scheme, for the nonlinear perturbed Schrödinger equation. …


Normalized Solutions For Sobolev Critical Schrödinger-Bopp-Podolsky Systems, Yuxin Li, Xiaojun Chang, Zhaosheng Feng Sep 2023

Normalized Solutions For Sobolev Critical Schrödinger-Bopp-Podolsky Systems, Yuxin Li, Xiaojun Chang, Zhaosheng Feng

School of Mathematical & Statistical Sciences Faculty Publications

We study the Sobolev critical Schr¨odinger-Bopp-Podolsky system −∆u + φu = λu + µ|u|p−2u + |u|4u in R3, −∆φ + ∆2φ = 4πu2 in R3, under the mass constraint u2 dx = c R3 for some prescribed c > 0, where 2 < p < 8/3, µ > 0 is a parameter, and λ ∈ R is a Lagrange multiplier. By developing a constraint minimizing approach, we show that the above system admits a local minimizer. Furthermore, we establish the existence of normalized ground state solutions.


Advances And Perspectives Of Using Stable Isotope Probing (Sip)-Based Technologies In Contaminant Biodegradation, Jinha Kim, Myung Hwangbo, Chih-Hsuan Shih, Kung-Hui Chu Sep 2023

Advances And Perspectives Of Using Stable Isotope Probing (Sip)-Based Technologies In Contaminant Biodegradation, Jinha Kim, Myung Hwangbo, Chih-Hsuan Shih, Kung-Hui Chu

School of Earth, Environmental, & Marine Sciences Faculty Publications

Stable isotope probing (SIP) is a powerful tool to study microbial community structure and function in both nature and engineered environments. Coupling with advanced genomics and other techniques, SIP studies have generated substantial information to allow researchers to draw a clearer picture of what is occurring in complex microbial ecosystems. This review provides an overview of the advances of SIP-based technologies over time, summarizes the status of SIP applications to contaminant biodegradation, provides critical perspectives on ecological interactions within the community, and important factors (controllable and non-controllable) to be considered in SIP experimental designs and data interpretation. Current trend and …


Chloeia Rozbaczyloi, A New Species Of Polychaete (Archinominae: Amphinomidae) And First Record Of The Family For The Nazca Ridge, Southeastern Pacific Ocean, Juan I. Cañete, María S. Romero, Erin E. Easton, Ariadna Mecho, Javier Sellanes Sep 2023

Chloeia Rozbaczyloi, A New Species Of Polychaete (Archinominae: Amphinomidae) And First Record Of The Family For The Nazca Ridge, Southeastern Pacific Ocean, Juan I. Cañete, María S. Romero, Erin E. Easton, Ariadna Mecho, Javier Sellanes

School of Earth, Environmental, & Marine Sciences Faculty Publications

Highlights

  • A new species of amphinomid polychaete, Chloeia rozbaczyloi sp. nov. is described.

  • The new species inhabits poorly explored seamounts of the remote Nazca Ridge off Chile.

  • This finding constitutes the first report of the genus Chloeia for Chilean waters.

  • Genetic data for Chloeia rozbaczyloi sp. nov is provided.

  • The new species is reported for seamounts lying within the recently created Nazca Desventuradas Marine Park.

Abstract

The amphinomid polychaete Chloeia rozbaczyloi sp. nov., collected from seamounts of the Nazca Ridge (NR), northwest of Desventuradas islands, southeastern Pacific Ocean, is described. The new species was observed on only two of seven …


Constrained Quantization For A Uniform Distribution With Respect To A Family Of Constraints, Megha Pandey, Mrinal Kanti Roychowdhury Sep 2023

Constrained Quantization For A Uniform Distribution With Respect To A Family Of Constraints, Megha Pandey, Mrinal Kanti Roychowdhury

School of Mathematical & Statistical Sciences Faculty Publications

In this paper, with respect to a family of constraints for a uniform probability distribution we determine the optimal sets of n-points and the nth constrained quantization errors for all positive integers n. We also calculate the constrained quantization dimension and the constrained quantization coefficient. The work in this paper shows that the constrained quantization dimension of an absolutely continuous probability measure depends on the family of constraints and is not always equal to the Euclidean dimension of the underlying space where the support of the probability measure is defined.


Complexity Of Verification In Self-Assembly With Prebuilt Assemblies, David Caballero, Timothy Gomez, Robert Schweller, Tim Wylie Sep 2023

Complexity Of Verification In Self-Assembly With Prebuilt Assemblies, David Caballero, Timothy Gomez, Robert Schweller, Tim Wylie

Computer Science Faculty Publications

We analyze the complexity of two fundamental verification problems within a generalization of the two-handed tile self-assembly model (2HAM) where initial system assemblies are not restricted to be singleton tiles, but may be larger prebuilt assemblies. Within this model we consider the producibility problem, which asks if a given tile system builds, or produces, a given assembly, and the unique assembly verification (UAV) problem, which asks if a given system uniquely produces a given assembly. We show that producibility is NP-complete and UAV is coNPNP -complete even when the initial assembly size and temperature threshold are both bounded by a …


Qc-Odkla: Quantized And Communication-Censored Online Decentralized Kernel Learning Via Linearized Admm, Ping Xu, Yue Wang, Xiang Chen, Zhi Tian Sep 2023

Qc-Odkla: Quantized And Communication-Censored Online Decentralized Kernel Learning Via Linearized Admm, Ping Xu, Yue Wang, Xiang Chen, Zhi Tian

Electrical and Computer Engineering Faculty Publications

This article focuses on online kernel learning over a decentralized network. Each agent in the network receives online streaming data and collaboratively learns a globally optimal nonlinear prediction function in the reproducing kernel Hilbert space (RKHS). To overcome the curse of dimensionality issue in traditional online kernel learning, we utilize random feature (RF) mapping to convert the nonparametric kernel learning problem into a fixed-length parametric one in the RF space. We then propose a novel learning framework, named online decentralized kernel learning via linearized ADMM (ODKLA), to efficiently solve the online decentralized kernel learning problem. To enhance communication efficiency, we …


Axion-Polaritons In The Magnetic Dual Chiral Density Wave Phase Of Dense Qcd, Efrain J. Ferrer, Vivian De La Incera Sep 2023

Axion-Polaritons In The Magnetic Dual Chiral Density Wave Phase Of Dense Qcd, Efrain J. Ferrer, Vivian De La Incera

Physics & Astronomy Faculty Publications

We investigate the propagation of electromagnetic radiation in the magnetic dual chiral density wave (MDCDW) phase of dense quark matter. Considering the theory of low-energy fluctuations in this phase, we show how linearly polarized photons reaching the MDCDW medium couple to the fluctuation field to produce two hybridized modes of propagation that we call in analogy with similar phenomenon in condensed matter physics axion polaritons, one of them being gapless and the other gapped. The gapped mode's gap is proportional to the background magnetic field and inversely proportional to the amplitude of the inhomogeneous condensate. The generation of axion …


Empowering Foot Health: Harnessing The Adaptive Weighted Sub-Gradient Convolutional Neural Network For Diabetic Foot Ulcer Classification, Abdullah Alqahtani, Shtwai Alsubai, Mohamudha Parveen Rahamathulla, Abdu Gumaei, Mohemmed Sha, Yu-Dong Zhang, Muhammad Attique Khan Sep 2023

Empowering Foot Health: Harnessing The Adaptive Weighted Sub-Gradient Convolutional Neural Network For Diabetic Foot Ulcer Classification, Abdullah Alqahtani, Shtwai Alsubai, Mohamudha Parveen Rahamathulla, Abdu Gumaei, Mohemmed Sha, Yu-Dong Zhang, Muhammad Attique Khan

School of Podiatric Medicine Publications

In recent times, DFU (diabetic foot ulcer) has become a universal health problem that affects many diabetes patients severely. DFU requires immediate proper treatment to avert amputation. Clinical examination of DFU is a tedious process and complex in nature. Concurrently, DL (deep learning) methodologies can show prominent outcomes in the classification of DFU because of their efficient learning capacity. Though traditional systems have tried using DL-based models to procure better performance, there is room for enhancement in accuracy. Therefore, the present study uses the AWSg-CNN (Adaptive Weighted Sub-gradient Convolutional Neural Network) method to classify DFU. A DFUC dataset is considered, …


Saturating Growth Rate Against Phosphorus Concentration Explained By Macromolecular Allocation, Gabrielle Armin, Jongsun Kim, Keisuke Inomura Aug 2023

Saturating Growth Rate Against Phosphorus Concentration Explained By Macromolecular Allocation, Gabrielle Armin, Jongsun Kim, Keisuke Inomura

School of Earth, Environmental, & Marine Sciences Faculty Publications

The saturating relationship between phytoplankton growth rate and environmental nutrient concentration has been widely observed, yet the mechanisms behind the relationship remain elusive. Here, we use a mechanistic model of phytoplankton and show that the saturating relationship between growth rate and phosphorous concentration can be interpreted by intracellular macromolecular allocation. At low nutrient levels, the diffusive nutrient transport linearly increases with the phosphorous concentration, while the internal phosphorous requirement increases with the growth rate, leading to a non-linear increase in the growth rate with phosphorous. This increased phosphorous requirement is due to the increased allocation to biosynthetic and photosynthetic molecules. …


Hellings And Downs Correlation Of An Arbitrary Set Of Pulsars, Bruce Allen, Joseph D. Romano Aug 2023

Hellings And Downs Correlation Of An Arbitrary Set Of Pulsars, Bruce Allen, Joseph D. Romano

Physics & Astronomy Faculty Publications

Pulsar timing arrays (PTAs) detect gravitational waves (GWs) via the correlations they induce in the arrival times of pulses from different pulsars. We assume that the GWs are described by a Gaussian ensemble, which models the confusion noise produced by expected PTA sources. The mean correlation h2μu(γ) as a function of the angle γ between the directions to two pulsars was predicted by Hellings and Downs in 1983. The variance σ2tot(γ) in this correlation was recently calculated [B. Allen, Variance of the Hellings-Downs correlation, Phys. Rev. D 107, 043018 (2023)] for a single noise-free pulsar pair at angle γ, …


Hellings And Downs Correlation Of An Arbitrary Set Of Pulsars, Bruce Allen, Joseph D. Romano Aug 2023

Hellings And Downs Correlation Of An Arbitrary Set Of Pulsars, Bruce Allen, Joseph D. Romano

Physics & Astronomy Faculty Publications

Pulsar timing arrays (PTAs) detect gravitational waves (GWs) via the correlations they induce in the arrival times of pulses from different pulsars. We assume that the GWs are described by a Gaussian ensemble, which models the confusion noise produced by expected PTA sources. The mean correlation h2μu(γ) as a function of the angle γ between the directions to two pulsars was predicted by Hellings and Downs in 1983. The variance σ2tot(γ) in this correlation was recently calculated [B. Allen, Variance of the Hellings-Downs correlation, Phys. Rev. D 107, 043018 (2023)] for a single noise-free pulsar pair at angle γ, …


Stability Analyses On The Effect Of Vaccination And Contact Tracing In Monkeypox Virus Transmission, Solomon Eshun, Richmond Essieku, James Ladzekpo Aug 2023

Stability Analyses On The Effect Of Vaccination And Contact Tracing In Monkeypox Virus Transmission, Solomon Eshun, Richmond Essieku, James Ladzekpo

School of Mathematical & Statistical Sciences Faculty Publications

Monkeypox is a significant health concern due to its potential for morbidity and occasional mortality. Vaccination and effective contact tracing play pivotal roles in controlling infectious diseases, including monkeypox. This study aims to contribute to our understanding of monkeypox dynamics by developing a comprehensive mathematical model that incorporates key factors such as vaccination, quarantining, and contact tracing. Through rigorous sensitivity analysis, we explore the impact of varying vaccination coverage and contact tracing on the disease’s dynamics. In particular, we investigate the dynamics of the disease in relation to variable vaccination coverage and contact tracing. Our findings highlight the critical role …