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Full-Text Articles in Life Sciences

Phytochemical Composition And Bioactivities Of Roselle (Hibiscus Sabdariffa L.) Extracts Obtained By Infusion, Ethanolic Maceration, And Maltodextrin-Assisted Drying, Risna Silvianti, Warsito Warsito, Elok Zubaidah, Zubaidah Ningsih, Aqidatul Izza May 2026

Phytochemical Composition And Bioactivities Of Roselle (Hibiscus Sabdariffa L.) Extracts Obtained By Infusion, Ethanolic Maceration, And Maltodextrin-Assisted Drying, Risna Silvianti, Warsito Warsito, Elok Zubaidah, Zubaidah Ningsih, Aqidatul Izza

Karbala International Journal of Modern Science

Roselle (Hibiscus sabdariffa L.) is rich in phenolic compounds and anthocyanins, but the extraction method may influence its chemical composition and biological activity. This study compared hot-water infusion, ethanolic maceration, and maltodextrin-assisted drying. It aimed to examine the relationship between the extraction method, chemical profile, and bioactivity. The resulting extracts (EI, EM, and EP) were analyzed for total phenolic, flavonoid, and anthocyanin, LC-HRMS profiles, and antioxidant capacity by the FRAP assay. Antibacterial analysis was conducted against Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 25923) using agar well diffusion. Cytotoxicity tests (MTT, 24 h) were performed against HT-29, 4T1, …


Effects Of Warming On Growth And Leaf Colonization By Litter Mat-Forming Fungi In A Wet Tropical Forest In Puerto Rico, Ari E. Puentes, D. Jean Lodge, Deyaneira A. Ortiz-Iglesias, Tatiana Barreto-Vélez, Laura C. Rubio-Lebrón, Hieu Chu, Christine S. O'Connell, Sasha C. Reed, Tana E. Wood May 2026

Effects Of Warming On Growth And Leaf Colonization By Litter Mat-Forming Fungi In A Wet Tropical Forest In Puerto Rico, Ari E. Puentes, D. Jean Lodge, Deyaneira A. Ortiz-Iglesias, Tatiana Barreto-Vélez, Laura C. Rubio-Lebrón, Hieu Chu, Christine S. O'Connell, Sasha C. Reed, Tana E. Wood

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Wet tropical forests are experiencing rising temperatures and increased frequency and intensity of extreme climatic events, such as cyclones, which can increase rates of soil erosion and surface runoff. Fungal litter mats, formed by agaric decomposer fungi, play a crucial role in stabilizing slopes, preventing erosion, and aiding nutrient cycling; however, little is known about how warming affects litter mat growth and function. We investigated two litter mat-forming fungi, Gymnopus johnstonii and Marasmius aff. crinis-equi, in warmed (+4°C above ambient) and control plots in the Luquillo Experimental Forest, Puerto Rico. Growth and time-to-leaf colonization were monitored over 6 weeks …


Deforestation Dynamics In The Amazon: Impacts, Socio-Environmental Drivers And Restoration Pathways, Maria Natalia Rodriguez May 2026

Deforestation Dynamics In The Amazon: Impacts, Socio-Environmental Drivers And Restoration Pathways, Maria Natalia Rodriguez

Master's Projects and Capstones

The Amazon, which is the largest tropical rainforest in the world, experienced 542,581 km² of forest loss between the years 2000 and 2020. The process of deforestation endangers the ecological system results which maintain ecosystem connectivity and the Earth's climate system. The Amazon rainforest supplies essential ecological services which include maintaining soil fertility, storing carbon, purifying water and climate stability. The fundamental ecosystem of this area faces new threats because of increasing forest destruction. The research study adopts a combined methodology that uses Geographic Information Systems (GIS) with a comprehensive literature review to study Amazon deforestation patterns and its driving …


Lowland Tropical Forests Remain A Methane Sink Under Warming And Long-Term Hurricane Disturbance Recovery, Gabriele Larocca Conte, Lucia Zuvela, Rachel Cruz-Pérez, Tatiana Barreto-Vélez, Nibia Becerra-Santillan, Sophia F. Campbell, Hieu P. Chu, Trung Dam, Iana F. Grullón-Penkova, Miriam Kleit, Deyaneira A. Ortiz-Iglesias, Laura C. Rubio-Lebrón, Molly A. Cavaleri, Sasha C. Reed, Debjani Sihi, Tana E. Wood, Christine S. O'Connell May 2026

Lowland Tropical Forests Remain A Methane Sink Under Warming And Long-Term Hurricane Disturbance Recovery, Gabriele Larocca Conte, Lucia Zuvela, Rachel Cruz-Pérez, Tatiana Barreto-Vélez, Nibia Becerra-Santillan, Sophia F. Campbell, Hieu P. Chu, Trung Dam, Iana F. Grullón-Penkova, Miriam Kleit, Deyaneira A. Ortiz-Iglesias, Laura C. Rubio-Lebrón, Molly A. Cavaleri, Sasha C. Reed, Debjani Sihi, Tana E. Wood, Christine S. O'Connell

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Methane (CH4) is a potent greenhouse gas, and tropical forests account for roughly one–third of global atmospheric CH4 uptake by soils. Projected warming and more frequent hurricanes in these ecosystems may alter soil CH4 sink strength, as warmer and wetter soils enhance methanogenesis activity. We measured soil CH4 and CO2 efflux during the calendar summer months of 2023 and 2024 alongside continuous records of soil moisture, soil and air temperature, and precipitation in an in–situ warming experiment (TRACE) located in a lowland tropical forest in Puerto Rico, six to seven years after Hurricanes Irma …


Replication And Architectural Enhancement Of Omni Aggregation Networks, Matteo Calviello May 2026

Replication And Architectural Enhancement Of Omni Aggregation Networks, Matteo Calviello

Rose-Hulman Undergraduate Research Publications

Single Image Super-Resolution (SISR) reconstructs high-resolution images from low-resolution inputs, a capability valuable across many application domains. This thesis focuses on the replication and architectural enhancement of the Omni Aggregation Network (OAN), a lightweight super-resolution architecture designed to balance reconstruction quality with computational efficiency through a novel omni-axis self-attention mechanism.

Independent replication remains a persistent challenge in machine learning research, and this work addresses that issue directly. Initial replication attempts trailed the original reported results by approximately 6-10% in performance metrics before several undocumented implementation details were identified. After correcting these discrepancies, the replicated implementation achieved results within 4% of …


Somatic Prosthetics For Planetary Resonance, Disha Dharesh Kumar R May 2026

Somatic Prosthetics For Planetary Resonance, Disha Dharesh Kumar R

Masters Theses

This thesis investigates how industrial design can transcend extractive technological paradigms in favor of relational interfaces that foster planetary attunement. Framing the climate crisis as a 'crisis of imagination', the research challenges the Western bifurcation of nature and culture by drawing on Indic cosmologies- which recognize stones, plants, and ecosystems as conscious at different levels and participants in a shared cosmic field. By synthesizing research in Biosemiotics, Quantum Information Pansycishm, and Neuroscience, the project redefines intelligence as a distributed, more-than-human phenomenon.

The research materializes as a speculative design artifact: a device that functions as a somatic prosthetic for planetary resonance. …


Environmental Mercury Alters Immune Pathways Linked To Autoimmune Risk In Mice Mirroring Humans, Maurgan Lee, Paul Stemmer, Randall Gill, Allen Rosenspire, Anil Aranha, Heather Gibson May 2026

Environmental Mercury Alters Immune Pathways Linked To Autoimmune Risk In Mice Mirroring Humans, Maurgan Lee, Paul Stemmer, Randall Gill, Allen Rosenspire, Anil Aranha, Heather Gibson

Medical Student Research Symposium

Background and Purpose: Mercury is a pervasive environmental contaminant, and human epidemiologic studies have linked chronic low-level exposure to increased autoimmune disease-risk. Dysregulated lymphocyte activation and impaired signaling tolerance are central mechanisms in human autoimmunity. Protein phosphorylation governs lymphocyte differentiation and function, alterations in phosphoproteomic networks may represent a signature of immune disruption. This study evaluates how low dose mercury exposure modifies B and T cell abundance and intracellular signaling patterns in BALB/c and Diversity Outbred (DO) mice.

Methods: BALB/c and DO mice were exposed to low dose HgCl2 in their water for two weeks or provided standard water controls. …


Beyond Stabilization: Biological Healing, Structural Exclusion, And The Recovery Gap After Border-Fall Trauma At The U.S.-Mexico Border, Julia Robinson May 2026

Beyond Stabilization: Biological Healing, Structural Exclusion, And The Recovery Gap After Border-Fall Trauma At The U.S.-Mexico Border, Julia Robinson

Undergraduate Honors Theses

This honors thesis examines the biochemical, ethical, and public health consequences of insufficient post-operative follow-up care for undocumented immigrants injured in border falls. Discussing pathways of inflammation resolution, wound healing, and bone remodeling, this thesis argues that recovery depends on tightly regulated molecular and cellular processes that are highly vulnerable to disruption without continued monitoring and rehabilitation (Loi et al., 2016; Maruyama et al., 2020). When follow-up care is absent, these processes can be predicted to derail, leading to infection, impaired healing, and permanent disability (Chung & Sohn, 2025; Howard et al., 2020; Kruidenier et al., 2018). Framed through principles …


Do Cover Crops Influence Beneficial And Herbivorous Arthropod Communities Across Growing Seasons?, Adegboyega Fajemisin, Satinderpal Kaur, Alejandro Vasquez, Alexis Racelis, Rupesh R. Kariyat May 2026

Do Cover Crops Influence Beneficial And Herbivorous Arthropod Communities Across Growing Seasons?, Adegboyega Fajemisin, Satinderpal Kaur, Alejandro Vasquez, Alexis Racelis, Rupesh R. Kariyat

School of Earth, Environmental, & Marine Sciences Faculty Publications

Cover crops provide multiple ecosystem services in agriculture, yet their influence on arthropod communities remains poorly understood, especially in commercial farming. Despite their potential benefits, it remains unexplored how cover crops affect arthropod community dynamics across multiple growing seasons. We conducted a two-year study across three commercial farms in the Lower Rio Grande Valley, Texas, to examine how cover crops influence arthropod community composition and abundance, whether beneficial arthropods (natural enemies and pollinators) persist into cash-crop phases, and how cover crops affect natural enemy–herbivore relationships. We compared arthropod communities between cover-crop treatments and control plots and tracked responses through subsequent …


Enhanced No₂ Gas Sensing Using Silver-Doped Cadmium Telluride Nanocrystalline Thin Films, Tunis Balasim Hassan May 2026

Enhanced No₂ Gas Sensing Using Silver-Doped Cadmium Telluride Nanocrystalline Thin Films, Tunis Balasim Hassan

Karbala International Journal of Modern Science

Nitrogen dioxide (NO₂) is a toxic pollutant that necessitates sensitive and reliable monitoring systems. Conventional gas sensors often lack adequate responsiveness and fast recovery under changing conditions and therefore create a need for semiconductors with enhanced performance, especially at high industrial temperatures (around 250 °C). The study therefore aims to synthesis and evaluate silver-doped cadmium telluride (Ag:CdTe) thin films as NO₂ gas sensors. Pure CdTe and Ag:CdTe with silver concentrations of 5, 10, and 15 wt% were prepared by a co-precipitation process. XRD verified cubic symmetry with a progressive fall in crystallite size (6.67 nm to 5.46 nm at 15 …


Microtubules In Breast Cancer: Exploring The Α/Β-Tubulin Toggle Switch And Its Implications In Human Breast Cancer, Annemarie Ianos May 2026

Microtubules In Breast Cancer: Exploring The Α/Β-Tubulin Toggle Switch And Its Implications In Human Breast Cancer, Annemarie Ianos

Student Theses and Dissertations

Microtubules, composed of a/b-tubulin heterodimers, play a central role in breast cancer tumor growth by polymerizing, leading to metastasis and depolymerizing, contributing to proliferation. Human enzymes protein kinase Ca (PKC-a) and cyclin-dependent kinase 1 (Cdk-1) mediate phosphorylation at sites a:Ser165 and b:Ser172, respectively, influencing the growth of microtubules. It is possible that alternating phosphorylation at these sites contribute to an a/b-tubulin “toggle switch” that mediates microtubule instability and tumor growth.

The project investigates the influence of the toggle switch model on microtubule stability by determining the impact of mutants (a:S165D, a:S165N, a:S165SP, b:S172SP and a:S165SP/b:S172S …


Computational Design Of Peptides And Proteins Through Machine Learning Approaches, Emily J. Hendrix May 2026

Computational Design Of Peptides And Proteins Through Machine Learning Approaches, Emily J. Hendrix

Chemistry and Chemical Biology ETDs

Advancements in machine learning have emerged as a pivotal tool in computational biochemistry, offering new advancements to address challenges in protein structure and function. However, current machine-learning approaches offer limited insight in understanding protein dynamics. The purpose of this work is to combine traditional physics-based computational tools, such as molecular dynamics and coarse-grained simulations, with recently developed AI-driven computational tools to bridge gaps and advance the understanding of proteins in both structural and dynamic aspects. I investigated several approaches such as (i) traditional physics-based methods to study protein conformation and ensembles; (ii) identifying a peptide inhibitor for the PICK1 PDZ …


The Extraction And Chemical Characterization Of The Avian Pigments Turacin And Turacoverdin, Sarah R. Bekkali May 2026

The Extraction And Chemical Characterization Of The Avian Pigments Turacin And Turacoverdin, Sarah R. Bekkali

Honors Scholar Theses

Bird coloration is a trait that extends beyond mere aesthetics as it has an extensive range of biological significance. Plumage patterns and hues can influence camouflage, mate choice, social dominance, and physiological performance. Bird fitness, their ability to survive and reproduce, is greatly dependent on color. Melanins, carotenoids, and pterins are well-studied pigment systems that are commonly found across many avian species’. Alternatively, porphyrin-based pigments are rare and less-studied as they only found in turacos a sub-Saharan African bird belonging to the family Musophagidae. This thesis focuses on two pigments of interest: turacin, the deep crimson-red pigment found in …


Accuracy Of Parameter Estimation For A Simple Gene Regulatory Network Model Is Sensitive To Network Motif, Number Of Parameters Estimated, And Magnitude And Direction Of Regulatory Relationships, Nikki C. Chun, Kam Dahlquist May 2026

Accuracy Of Parameter Estimation For A Simple Gene Regulatory Network Model Is Sensitive To Network Motif, Number Of Parameters Estimated, And Magnitude And Direction Of Regulatory Relationships, Nikki C. Chun, Kam Dahlquist

Honors Thesis

A gene regulatory network (GRN) is a set of transcription factors that regulate the expression of genes encoding other transcription factors. The dynamics of a GRN explain how gene expression changes over time. GRNmap is a MATLAB software package that uses ordinary differential equations to model dynamics of small-scale GRNs. We used the program to estimate production rates, expression thresholds, and regulatory weights for each transcription factor in three related literature-derived GRNs based on yeast cold shock microarray data previously collected in the Dahlquist Lab. We noticed large differences in estimated weight values when 1-2% of the expression values were …


Interpretable Deep Learning Models For Trustworthy Prediction Of Enzyme Functions, Louis Dumontet May 2026

Interpretable Deep Learning Models For Trustworthy Prediction Of Enzyme Functions, Louis Dumontet

UNLV Theses, Dissertations, Professional Papers, and Capstones

Trustworthy prediction of enzyme function from protein sequences remains a central challenge in computational biology, particularly when annotated data are limited, imbalanced, or incomplete. This dissertation develops interpretable deep learning methods for enzyme discovery and enzyme function prediction from amino acid sequences. First, it introduces PEPIC, an interpretable convolutional neural network for substrate-level prediction of hydrolytic plastic-degrading enzymes. Using curated and expanded sequence datasets, PEPIC improved predictive performance over benchmark methods, identified sequence regions aligned with catalytic and substrate-binding residues, and supported the discovery and experimental validation of a previously uncharacterized PET-degrading enzyme. Second, this dissertation investigates the integration of …


From Flight To Hatching: Adult Sexual Dimorphism, Life History, And Egg-Stage Ecology Of Pseudocotalpa Giulianii, Mandylene Mountain May 2026

From Flight To Hatching: Adult Sexual Dimorphism, Life History, And Egg-Stage Ecology Of Pseudocotalpa Giulianii, Mandylene Mountain

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Nevada endemic dune beetle Pseudocotalpa giulianii is currently known only from two dune systems in Amargosa Valley, Nevada, yet much of its life cycle occurs below the sand surface and remains poorly documented. This thesis addresses key gaps in adult-stage biology and egg-stage development that are relevant to understanding reproduction, vulnerability, and habitat requirements in this dunerestricted species.

To characterize adult sexual dimorphism and life history, I quantified morphological differences between males and females and measured sex-specific adult survival under laboratory conditions relative to the aboveground flight season. Males and females overlapped broadly in external body size, but tarsal …


Thermal Physiological Ecology Of The Relict Leopard Frog At Hot And Cold Springs, Robert P. Pelletier Iii May 2026

Thermal Physiological Ecology Of The Relict Leopard Frog At Hot And Cold Springs, Robert P. Pelletier Iii

UNLV Theses, Dissertations, Professional Papers, and Capstones

The relict leopard frog (Rana onca) once ranged across drainages in southern Nevada, northwestern Arizona, and southwestern Utah. Following a decline, the species only persisted in a few geothermally influenced hot springs, which led to the perspective that hot springs were high-quality habitat. Rana onca has been under intensive, multiagency management and the species has been translocated to establish additional populations, including at cold-water sites. Three research studies are presented into the thermal physiological ecology of R. onca with the aim of informing conservation strategy. The research was focused at a thermally influenced hot spring and a cold-water spring to …


Methylation-Dependent Regulatory Pathway That Governs The Stability Of The Sox Family Proteins And Related Developmental Regulators, Keshari Gayathri Rajawasam May 2026

Methylation-Dependent Regulatory Pathway That Governs The Stability Of The Sox Family Proteins And Related Developmental Regulators, Keshari Gayathri Rajawasam

UNLV Theses, Dissertations, Professional Papers, and Capstones

The SRY (Sex-determining Region Y) protein is a transcription factor encoded on the Y chromosome and is the key regulator responsible for initiating male sex determination in mammals. During early embryonic development, SRY activates the genetic program that leads to testis formation by promoting the expression of downstream genes involved in male gonadal differentiation. Mutations or dysregulation of SRY can lead to disorders of sex development such as male-to-female sex conversion and hermaphroditism, highlighting its critical role in sex determination.

SRY belongs to the SOX (SRY-related HMG-box) family of transcription factors, which includes the proteins SOX1, SOX2 and SOX3. These …


Unknowing Sacrifices: Public Health And Radiation Illness In New Mexico And Nevada, 1940s-1960s, Beatriz Avila-Marquez May 2026

Unknowing Sacrifices: Public Health And Radiation Illness In New Mexico And Nevada, 1940s-1960s, Beatriz Avila-Marquez

UNLV Theses, Dissertations, Professional Papers, and Capstones

The detonation of the first atomic bomb in the early morning of July 16, 1945, in New Mexico welcomed the atomic age that forever changed the world. After that day, thousands of lives were lost due to nuclear weapons, and hundreds of thousands more continued to suffer from the effects of atomic testing. The Atomic Energy Commission, fueled by the arms race of the Cold War, chose Nevada to continue the United States’ nuclear weapons testing. Knowledge of the dangers of radiation exposure, the effects of radiation, and techniques to prevent exposure are now available in part due to the …


Multiscale Modeling Of Chemoattractant-Guided Collective Cell Migration In The Drosophila Egg Chamber, Lara Scott, Bradford E. Peercy, Meghan Kwon, Michelle Starz-Gaiano May 2026

Multiscale Modeling Of Chemoattractant-Guided Collective Cell Migration In The Drosophila Egg Chamber, Lara Scott, Bradford E. Peercy, Meghan Kwon, Michelle Starz-Gaiano

Biology and Medicine Through Mathematics Conference

No abstract provided.


Impact Of Innate, Adaptive, And Cellular Immunity On Viral Reproductive Cycle: A Stochastic Extinction Analysis, Rahnuma Islam, David Swigon May 2026

Impact Of Innate, Adaptive, And Cellular Immunity On Viral Reproductive Cycle: A Stochastic Extinction Analysis, Rahnuma Islam, David Swigon

Biology and Medicine Through Mathematics Conference

No abstract provided.


Phase-Preserving Machine Learning Forecasting Of Nonlinear Predator–Prey Dynamics, Saira Batool, Muhammad Imran, Brett Mckinney May 2026

Phase-Preserving Machine Learning Forecasting Of Nonlinear Predator–Prey Dynamics, Saira Batool, Muhammad Imran, Brett Mckinney

Biology and Medicine Through Mathematics Conference

No abstract provided.


Modeling Epidemic Dynamics With Renewal Processes And General Lifetime Distributions, Divine Wanduku, Divine Wanduku May 2026

Modeling Epidemic Dynamics With Renewal Processes And General Lifetime Distributions, Divine Wanduku, Divine Wanduku

Biology and Medicine Through Mathematics Conference

No abstract provided.


Remote Sensing To Detect Crop Damage By An Invasive Species, Cole Butler May 2026

Remote Sensing To Detect Crop Damage By An Invasive Species, Cole Butler

Biology and Medicine Through Mathematics Conference

No abstract provided.


A New Framework For Studying Transient Reactivity In Two-Dimensional Linear Systems., Mary Lou Zeeman, Alanna Haslam-Hyde, James Broda May 2026

A New Framework For Studying Transient Reactivity In Two-Dimensional Linear Systems., Mary Lou Zeeman, Alanna Haslam-Hyde, James Broda

Biology and Medicine Through Mathematics Conference

No abstract provided.


Dynamic Homeostasis In Relaxation And Bursting Oscillations, Christopher J. Ryzowicz May 2026

Dynamic Homeostasis In Relaxation And Bursting Oscillations, Christopher J. Ryzowicz

Biology and Medicine Through Mathematics Conference

No abstract provided.


How Human Behavior Shapes Epidemic Dynamics, Leah Lejeune, Navid Ghaffarzadegan, Lauren M. Childs, Omar Saucedo May 2026

How Human Behavior Shapes Epidemic Dynamics, Leah Lejeune, Navid Ghaffarzadegan, Lauren M. Childs, Omar Saucedo

Biology and Medicine Through Mathematics Conference

No abstract provided.


Dynamics For Complex Quadratic Networks, Templates And Mutations, Anca R. Radulescu, Eva Kaslik, Alexander Fikl, Sarah Muldoon, Johan Nakuci, Mark Comerford May 2026

Dynamics For Complex Quadratic Networks, Templates And Mutations, Anca R. Radulescu, Eva Kaslik, Alexander Fikl, Sarah Muldoon, Johan Nakuci, Mark Comerford

Biology and Medicine Through Mathematics Conference

No abstract provided.


Delineating Differences In Firing Rate Estimates Of Healthy And Parkinsonian Single-Unit Basal Ganglia Recordings, Richard R. Foster, Cheng Ly May 2026

Delineating Differences In Firing Rate Estimates Of Healthy And Parkinsonian Single-Unit Basal Ganglia Recordings, Richard R. Foster, Cheng Ly

Biology and Medicine Through Mathematics Conference

No abstract provided.


A Size-Structured Approach For Modeling Coral-Algal Dynamics, Anayse Miller, Julie C. Blackwood, Lauren M. Childs May 2026

A Size-Structured Approach For Modeling Coral-Algal Dynamics, Anayse Miller, Julie C. Blackwood, Lauren M. Childs

Biology and Medicine Through Mathematics Conference

No abstract provided.