Digital Commons Network^™

Lead Bioremoval By Halotolerant Bacteria Isolated From Mangrove Rhizosphere Soils Of Saudi Arabia, Reda H. Amasha, Rawan A. Alhazzani

Journal of King Abdulaziz University: Marine Science

Bioremediation of hypersaline environments contaminated with heavy metals is challenging due to high salinity levels, particularly when using conventional microorganisms. This study aimed to isolate and identify halotolerant and halophilic bacteria from various mangrove rhizosphere soil samples in Saudi Arabia and to evaluate their ability to remove heavy metals under high-salinity conditions. Out of 27 isolated strains, LD57 and LR40 demonstrated the highest resistance to lead ions. Both isolates grew well at 37 °C in the presence of 3 M NaCl and recorded growth at varying concentrations of lead nitrate, ranging from 100 to 4500 ppm. The lead’s minimum inhibitory …

Molecular Docking And Antibacterial Activity Of Sesterterpenoids From Hyrtios Erectus, Hajer S. Alorfi, Nawal A. Albalawi

Journal of King Abdulaziz University: Marine Science

The search for new antibiotics remains urgent due to the continuous evolution of microbes and their resistance to currently available antibiotics. The organic extract of a specimen of the Red Sea sponge Hyrtios erectus collected off Jeddah coast was subjected to sequential chromatographic fractionation. Three sesterterpenoids (1–3) along with an indole alkaloid (4) were isolated from H. erectus. Structure elucidation of the isolated was accomplished using NMR, UV, and IR spectroscopy along with MS spectrometry. The antibacterial activity of the isolated sesterterpenoids (1–3) was assessed against a set of Gram-positive and negative …

A Systematic Literature Review Of Sustainable Ports Strategies And Initiatives In The Arabian Gulf Ports – Lessons For Saudi Arabia And Uae, Osayd Helal, Jane Haider, Jean-Paul Skeete, Sehwa Lim

Journal of King Abdulaziz University: Marine Science

This systematic review provides a comprehensive evaluation of sustainability strategies in Arabian Gulf ports, focusing on the interplay between technological advancements, green initiatives, and regulatory challenges. While Industry 4.0 technologies—such as automation, artificial intelligence, and electrification—have been integrated to enhance operational efficiency and reduce carbon emissions, the extent to which these innovations align with regional policy frameworks and geopolitical constraints remains insufficiently analysed.

To address this gap, this review synthesises insights from 25 peer-reviewed studies, employing a comparative framework to assess the adoption of sustainability practices in Arabian Gulf ports, focusing on their approaches toward sustainable port development. It is …

Assessment Of Microplastic Pollution In Economically Significant Fish Species From Libya’S Northeastern Mediterranean Coast, Mousa Kateesh, Tarek A. Temraz, Rafat Afifi Khattab

Journal of King Abdulaziz University: Marine Science

Microplastic pollution in marine ecosystems has become a pressing global environmental issue. However, there is limited information on the distribution of microplastics in Libyan territorial waters. This study investigates plastic waste pollution in five commercially important fish species from various marine habitats along the eastern Libyan coast (Ain El-Ghazala, Sousa, Ras Hilal, Alhaniyah, and Alhamama). A total of 75 fish specimens were collected, comprising 15 individuals from each species. The findings revealed that 38% of the sampled fish had ingested plastic debris, with microplastics being the predominant form. The Sousa region exhibited the highest contamination rate (54.46%), while Alhaniyah had …

Urbanization Impacts On Microplastic In Benthic Organisms And Sediment Of Small Islands, Andrio Wibowo, Suyud Warno Utomo

Journal of King Abdulaziz University: Marine Science

Indonesia is an archipelago country comprising thousands of islands, including small islands. Currently, small islands have experienced urbanization in the forms of land use developments and conversions from pristine ecosystems to settlements and tourism facilities, leading to the contamination of microplastics. Despite growing numbers of research on microplastic in water, there is still limited information about microplastic in the sediment and benthic, in particular in developed small island environments. This study compared the types of land use on the island from reserved areas, tourism, and settlement. The microplastics were characterized based on the shapes. The results confirm that land use …

New Fish-Based Multimetric Index For Appraising Shatt Al-Arab Ecological Quality, Laith Faisal Lazem

Journal of King Abdulaziz University: Marine Science

In recent years, there has been a growing need to develop biometric indicators that accurately reflect an area’s environmental quality and biological integrity. Various indicators have been developed and analyzed, focusing on functional, ecological, and organism-based indicators, particularly fish-related ones. The purpose of the current paper is to create the first fish-based multimetric index designed to evaluate the quality of water in the Shatt Al-Arab River (SAAR), known as Shatt Al-Arab Fish Index (SFI), which can also be applied to the Qarmat Ali River and other water bodies similar to the SAAR ecology. Data was collected from three stations along …

Trajectory Prediction Of Oil Spills In Sharm Obhur, Red Sea Using Hydrodynamic Modeling, Mohammed A. Bahattab, Gar Al-Nabi Ibrahim, V.R. Shamji

Journal of King Abdulaziz University: Marine Science

This research investigates the movement and impact of oil spills in Sharm Obhur, a coastal creek near Jeddah, in the Red Sea. Utilizing a high-resolution multi-beam echo sounder and the Delft3D-FLOW hydrodynamic simulation model, the study traces the oil spill trajectories, considering key factors such as meteorological conditions, spill volume, and oil properties. The model predicts the movement of the oil spill both within Sharm Obhur and its progression towards the Red Sea. Results from the model are intended to assist in the development of effective spill response strategies, improving navigation safety, protecting coral reefs, and preserving the local ecosystem. …

Preprocessing Improves The Edna Quality For 16s Rrna Metabarcoding Of Sediment Samples Of Solar Salterns, Jayanath Gopi, Bhavya Kachiprath, Solly Solomon, Sowmya P. Mohandas, Sajan C. Raju, Rosamma Philip

Journal of King Abdulaziz University: Marine Science

The present study examines the efficacy of pre- processing of sediment samples prior to DNA isolation to obtain high-quality eDNA for metagenomic analyses from crystallizer saltern pond in Goa during the salt harvesting phase. The quality of the extracted eDNA were confirmed through spectrophotometric analysis and PCR amplification of the 16S rRNA gene. The study showed that method 2 and 3 incorporating preprocessing of the sediment samples yielded better quality eDNA compared to the direct isolation protocol (method1). By adopting the best method i.e., preprocessing by sediment suspension- filtration, followed by DNA isolation, the eDNA was procured and subjected to …

Morphometric, Physiological, And Environmental Health Assessments Of Enhalus Acoroides From The Southeast Coast Of Bali, Indonesia, Made Pharmawati, Luh Putu Wrasiati, Ni Made Gari

Journal of King Abdulaziz University: Marine Science

Seagrasses function as primary producers and as spawning grounds and shelter for marine biota. Regardless of their relevance, seagrasses are under threat due to anthropogenic impacts and an increasing frequency of extreme climate events. Enhalus acoroides is a species of seagrass that is spread in the east and southeast waters of Bali, from Sanur Beach to Nusa Dua Beach. This study aims to analyze the differences in morphometry and the chlorophyll, proline, and malondialdehyde (MDA) content, a marker for oxidative stress in E. acoroides leaves at Pengastian Beach, Semawang Beach, and Samuh Beach, Bali. Samples were collected using line transect …

Latent And Sensible Heat Flux In The Red Sea And Gulf Of Aden Using The Nemo Ocean Model Simulation, Moaath Ghanem, Yassir Albouraee, Mohammed A. Alsaafani, Alaa Albarakati

Journal of King Abdulaziz University: Marine Science

The new configuration of NEMO (Nucleus for European Modelling of the Ocean) model in the Red Sea and Gulf of Aden was presented for analyzing latent heat flux (LHF) and sensible heat flux (SHF) patterns in the region. The model was setup with 1/20° horizontal resolution and 30 vertical layers, using ERA5 atmospheric data for surface forcing. The model output for LHF, and SHF was compared with KAUST-Buoy observations and many reanalysis products (the French Research Institute for Exploitation of the Sea (IFREMER) surface turbulence fluxes, Japanese Ocean Flux Data Sets with Use of Remote Sensing Observations (J-OFURO3), Objectively Analyzed …

Optimizing Kappaphycus Alvarezii Seedlings: Acclimatization And Cultivation Methods For Sustainable Seaweed Seed In Lombok Kodek Bay, Dasep Hasbullah, Fahrurrozi Fahrurrozi, Gagan Garnawansah, Zaenal Arifin Siregar, Wahyu Purbiantoro, Moh. Awaludin Adam, Idham Sumarto Pratama, Nurhalis Tarmin, Balkam F. Badi, Abdul Wahab, Raismin Kotta

Journal of King Abdulaziz University: Marine Science

This study explores the combined[-10pc]AU: Please specify the corresponding author name. effects of cultivation methods and acclimatization durations on the growth performance of Kappaphycus alvarezii, a tropical seaweed widely utilized in biostimulants and bioplastics. Cultivation methods included monoculture of Spinosum (SNP), monoculture of Cottonii (DNP), and polyculture of Spinosum and Cottonii (PSP), while acclimatization treatments involved durations of 0, 2, and 4 days before planting (DBA). Results demonstrated that the SNP system achieved the highest productivity, with maximum weight (142.8 g) and relative growth rate (RGR) of 3.21% per day observed under 0 DBA. The 2 DBA treatment was …

Change In Community Composition And Structure On Subtidal Rock Walls In The Gulf Of Maine Over Four Decades Of Warming, Breck A. Mccollum

Graduate Doctoral Dissertations

The Gulf of Maine (GOM) has faced many changes over the last 47 years from overfishing of its iconic cod fish stocks to the introduction on non-native species, but no change has been as dramatic as the warming ocean temperatures that began to increase rapidly in the 2010s. This thermal shift is due largely to the northward movement of the Gulf Stream current mixing with Arctic meltwater before entering the GOM. Average summer temperatures jumped by 3.35°C between the periods of 1980-1985 and 2015-2020. This warming trend, combined with an increasing frequency of marine heat wave events, has led to …

Intercontinental Variation In Population Genetics And Life-History Traits In Native And Invasive Populations Of The Aquatic Plants Myriophyllum Spicatum And Myriophyllum Sibiricum, Anastasia V. Mozharova

Graduate Doctoral Dissertations

Biological invasions pose significant threats to freshwater ecosystems worldwide, and understanding their evolutionary, genetic, and biogeographic drivers is essential for effective management. My dissertation integrates microsatellite and ITS rDNA data to examine the dynamics of both invasive and native populations of two closely related aquatic plant species, Myriophyllum spicatum (Eurasian watermilfoil) and M. sibiricum (Northern watermilfoil).

Myriophyllum spicatum is native to Eurasia, where it inhabits a variety of freshwater aquatic habitats. Since its introduction to North America in the mid-20th century, it has become highly invasive, forming dense underwater mats that outcompete native vegetation, reduce biodiversity, and degrade water quality. …

Netrin-1 Promotes Pancreatic Tumorigenesis And Innervation Through Neo1, Hiroki Kobayashi, Yosuke Ochiai, Junya Arai, Masahiro Hata, Feijing Wu, Masaki Sunagawa, Tadashi Iida, Taisuke Baba, Ermanno Malagola, Takayuki Tanaka, Zhengyu Jiang, Ruth A White, Xiaofei Zhi, Jin Qian, Quin T Waterbury, Ruhong Tu, Biyun Zheng, Yi Zeng, Hualong Zheng, Puran Zhang, Shuang Li, Leah B Zamechek, Jonathan S Labella, Takahiro Sugie, Atsushi Enomoto, Holger K Eltzschig, Carmine F Palermo, Iok In Christine Chio, Kenneth P Olive, Timothy C Wang

Faculty, Staff and Student Publications

Nerves can regulate tumorigenesis and cancer progression. However, clarification of the role of axon guidance molecules in tumorigenesis, innervation, and metastasis is required to better understand the tumor-promoting functions of nerves. Using murine KrasG12D-mutant pancreatic organoids, we screened axon guidance molecules and identified netrin-1 upregulation. Netrin-1 was also upregulated in vivo during pancreatic tumorigenesis in humans and mice. Mutant KRAS and β-adrenergic signaling upregulated netrin-1 and its receptor NEO1 in epithelial cells in part through the MAPK pathway. Ex vivo culture of celiac ganglia showed that netrin-1 promoted the axonogenesis of sympathetic neurons through nerve NEO1. In the Pdx1-Cre;LSL-KrasG12D/+ model, …

Speeding Up Interval Estimation For R2-Based Mediation Effect Of High-Dimensional Mediators Via Cross-Fitting, Zhichao Xu, Chunlin Li, Sunyi Chi, Tianzhong Yang, Peng Wei

Faculty, Staff and Student Publications

Mediation analysis is a useful tool in investigating how molecular phenotypes such as gene expression mediate the effect of exposure on health outcomes. However, commonly used mean-based total mediation effect measures may suffer from cancellation of component-wise mediation effects in opposite directions in the presence of high-dimensional omics mediators. To overcome this limitation, we recently proposed a variance-based R-squared total mediation effect measure that relies on the computationally intensive nonparametric bootstrap for confidence interval estimation. In the work described herein, we formulated a more efficient two-stage, cross-fitted estimation procedure for the R2 measure. To avoid potential bias, we performed …

Biomarker And Age At Onset Endophenotypes Offer New Insights Into The Genetic Etiology Of Alzheimer’S Disease, Joseph Bradley

Arts & Sciences Graduate Student Theses and Dissertations

Introduction: Alzheimer’s Disease (AD) remains among the top 10 causes of death in the United States and is projected to affect nearly 14 million people by 2050. To this point, studies of Alzheimer’s genetics and endophenotypes have yielded a bounty of results that culminated in the first disease-modifying drugs, lecanemab and donanemab, in 2022. Most of the genetic studies for Alzheimer’s disease to date have been focused on late-onset AD or Autosomal dominant AD, leaving a critical need for studying sporadic early-onset AD (EOAD; ~10% of cases). Furthermore, the demand for clinical portability has created a need for high-sensitivity proteomic …

Relationships Between Larval Fish Drift, Time Of Day And Discharge In An Ozark Stream, Daniel D. Magoulick, Christy L. Graham

Biological Sciences Faculty Publications and Presentations

We examined the relationship between larval fish numbers and discharge during a high flow event in Bear Creek, Arkansas, a small Ozark stream. Additionally, we examined the relationship between fish numbers and time of day, and the spatial distribution of families and size classes. A total of 3,083 fish from five families were collected. Leuciscidae was the dominant family collected, followed by Percidae, and Catostomidae. Larval fish in Bear Creek were not susceptible to increased discharge from the flood event, as all three families exhibited strong significant negative relationships to discharge at night when discharge began to decline. Larval fish …

Artificial Intelligence As A Catalyst For Systemic Sport Ecology, Ugo Arbieu, Laís Carneiro, Sonia Tieo, Franck Courchamp

Journal of Applied Sport Management

Artificial intelligence (AI) is reshaping both sport management and environmental science, yet these developments have largely evolved in parallel. AI can serve not merely as a technical tool but also as a catalyst for systemic sport ecology, a field that integrates sport, digital innovation and environmental sustainability. Advances in discriminative, generative and agentic AI enable the synthesis of complex ecological and sport-related data, improving monitoring, forecasting, resource efficiency, policy design, and decision-making across scales. In doing so, AI offers a pathway beyond fragmented sustainability interventions and can support holistic approaches to the interconnected crises of climate change, pollution, and biodiversity …

Systematic Literatur Review: Development Effectiveness E-Module Pbl-Based Learning To Improve Problem-Solving Skills In Ecosystem Material, Liziaruti Aurani Chong, Diana Vivanti Sigit, Ratna Komala, Rusdi Rusdi, Tri Handayani

Jurnal Pendidikan Sains

This study aims to analyze the effectiveness of developing e-modules based on Problem Based Learning (PBL) in improving students' problem-solving abilities in ecosystem material. The method used is Systematic Literature Review (SLR) by reviewing articles published in the period 2018–2025. The results of the analysis show that most of the research uses the descriptive method. Research and Development (RnD) with junior high and senior high school subjects, and produced N-Gain values ranging from 0.50 to 0.83, categorized as moderate to high. These findings demonstrate that PBL-based e-modules are capable of supporting the improvement of problem-solving skills through interactive, contextual, and …

Integration Of Islamic Values In Mathematics Learning, Ai Mulya, Surya Faradiba

Jurnal Pendidikan Sains

This study aims to identify the integration of Islamic values in mathematics learning and its contribution to student character development. The method used is a systematic literature study by reviewing relevant accredited scientific articles. The results of the study indicate that the integration of Islamic values is carried out through the preparation of Islamic-context-based mathematics problems, linking concepts to verses of the Qur'an and hadith, the application of ethnomathematics with Islamic cultural nuances, and the introduction of Islamic economic concepts. The dominant values that emerge include honesty, responsibility, discipline, justice, and piety. These findings indicate that the integration of Islamic …

Water Quality And Plankton Diversity Of Ahi River, Ohiya, Umuahia, Nigeria, Emeka Donald Anyanwu, Egor Katkov, Udeme Effiong Jonah, Amarachuku Ezinne Oji, Immaculate Chiamaka Enwereuzo

Journal of Bioresource Management

The plankton diversity of large and urban rivers has been extensively studied in Nigeria while small rural rivers that harbour rich aquatic biota receive little attention. The composition, abundance, and distribution of plankton of a rural river were assessed in relation to some physicochemical parameters. The study was carried out between May and October 2023 in 3 stations using standard methods. The physicochemical results were: temperature (25.2-27.0^oC), flow velocity (0.15-0.46 m/s), transparency (14.0-78.5cm), depth (51.0-105.0cm), pH (5.6-7.8), electrical conductivity (66.0-98.0 µS/cm), total dissolved solids (33.0-49.0 mg/l), turbidity (0.1-1.7 NTU), dissolved oxygen (3.2-6.4 mg/l), biochemical oxygen demand (1.0-2.7 mg/l), …

Psoriasis Treatments In The Stabilization Of Atherosclerosis: A Systematic Review, Lixin Ji, Sowmya Ravi, Laura Wright, Vi Nguyen, Jose Wiley, Milena Vukelic, Sangkyu Kim

School of Medicine Faculty Publications

This systematic review explores the relationship between achieving minimal disease activity in psoriasis and the progression of atherosclerosis. It investigates how biologic therapies and other treatments impact atherosclerosis markers, offering insights into therapeutic strategies. A comprehensive search of PubMed, Embase, and Web of Science was conducted from January 1, 2000, to April 1, 2023, using terms such as psoriasis, psoriatic arthritis, atherosclerosis, biologic therapy, vascular stiffness, carotid intima-media thickness (CIMT), and coronary computed tomography angiography (CCTA). Eligible studies were those involving human subjects over 18, written in English, that provided quantitative atherosclerosis markers, including CIMT, CCTA, arterial pulse wave velocity …

Understanding The Fidelity And Specificity Of Dna Polymerase I, Bill R. Miller Iii, Andrew V. Yeager, Jake A. Collins, Alexis Blake, Elise Tate, Carol A. Parish, Eugene Y. Wu

Chemistry Faculty Publications

High-fidelity DNA polymerases employ complex mechanisms to catalyze template-dependent DNA synthesis while quickly discarding mismatches. Atomic-level structural details about short-lived states during nucleotide discrimination are necessary to gain insight into the kinetic checkpoints that contribute to fidelity. We performed microsecond molecular dynamics simulations of DNA polymerase I, large fragment, from Bacillus stearothermophilus (Bacillus fragment, or BF) in complex with a template guanine and a mismatched thymidine triphosphate to observe the early events in the process of selection against a mismatch. Although the nucleobases formed a wobble base pair early, the mismatched pair was blocked from fully entering the active site …

Impact Of Chilling, Freezing, And Repeated Freeze–Thaw Cycles On Physical Quality Of Buffen, Chevon, And Chicken Meat, Tarique Ahmed Khokhar, Atta Hussain Shah, Muneer Ahmed Jamali, Asghar Ali Kamboh, Faiz Muhammad Khand, Muhammad Awais Soomro, Zafar Ali Khoso, Muhammad Mohsen Rahimoon

Journal of Bioresource Management

Chilling, freezing, and repeated freeze–thaw cycles are common meat preservation methods; however, they can alter key physicochemical properties. Comparative data across different species under standardized conditions are limited. To compare the effects of chilled storage, frozen storage, and repeated freeze–thaw cycles on pH, water-holding capacity (WHC), thaw loss, cooking loss, and drip loss in buffen (buffalo), chevon (goat), and chicken meat. Longissimus dorsi muscles from buffalo and goat, and breast meat from broiler chickens, were stored under chilled (2–4 °C), frozen (–10 to –12 °C), or repeated freeze–thaw conditions. "Measurements were performed at defined intervals of chilling, freezing and freeze …

Dcpr: A Deep Learning Framework For Circadian Phase Reconstruction, Xiao Han, Xiaochen Cen, Zhijin Li, Xiaobo Zhou, Zhiwei Ji

Faculty, Staff and Student Publications

Background: The circadian clock is an evolutionarily conserved system that orchestrates 24-h physiological rhythms through transcriptional and translational feedback loops. Mounting evidence suggests a bidirectional relationship between circadian rhythm alteration and disease progression, positioning the circadian clock as a potential therapeutic target. Due to the scarcity of high-resolution temporal omics data, it remains very challenging to elucidate the underlying regulatory mechanisms of the circadian system. As a practical alternative, public untimed transcriptomic datasets offer the potential to infer gene expression oscillations retrospectively. However, existing computational approaches for circadian phase estimation often suffer from limited predictive accuracy, reducing their ability to …

Towards Computational Methods In Medical Data Analysis: From Speech And Text To Imaging, Kristin Qi

Graduate Doctoral Dissertations

Early detection of cognitive decline and efficient medical image analysis remain critical challenges in healthcare. Traditional clinical assessments are infrequent and resource-intensive, while everyday speech data and unlabeled medical images remain largely unexploited. This dissertation develops computational methods integrating machine learning and artificial intelligence across speech, text, and imaging modalities to address challenges in medical data processing. For cognitive monitoring, this work first introduces methods using voice assistant systems to collect longitudinal speech data in home environments, demonstrating that incorporating historical session patterns significantly enhances detection of mild cognitive impairment. Building on this foundation, a framework combining large language model-driven …

In Silico Target Identification For Antioxidant And Anti-Inflammatory Activity Of Oil Palm Leaves Extract After Biotransformation Process, Galuh Permatasari, Irma Kresnawaty, Annisa Aulia Aksa, Djoko Santoso, Widodo Widodo

Makara Journal of Science

Oil palm leaf extract (OPLE) contains abundant phenolic and flavonoid compounds with recognized antioxidant and anti-inflammatory potential; however, its pharmacological applications remain underexplored. This study aimed to optimize the enrichment process of OPLE and characterize its bioactive compounds using integrated in vitro and in silico approaches. The extraction was optimized by incorporating trichloroacetic acid and extending the incubation time to 48 h, resulting in significantly increased total phenolic content and antioxidant activity compared with the control. LC–MS/MS profiling identified 14 flavonoid compounds with diverse biological functions. Among these, Rhamnetin-3-O-β-D-glucopyranoside, Kaempferol-3-O-rutinoside, and Nelumboroside A exhibited the strongest antioxidant and free radical …

Electrochemical Sensors Based On Graphene Oxide/Pedot:Pss Composite Decorated With Bimetallic Gold–Silver Nanoparticles For H2o2 Detection, Rayyan Azzahra Hidayat, Budi Riza Putra, Munawar Khalil, Wulan Tri Wahyuni

Makara Journal of Science

Hydrogen peroxide (H₂O₂) is a biomarker that indicates oxidative stress levels in the human body; thus, rapid and accurate detection methods are necessary to diagnose various disorders. This study developed a nonenzymatic electrochemical sensor for detecting H₂O₂ using bimetallic gold–silver nanoparticles (Au–Ag NPs) combined with graphene oxide and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)-modified glassy carbon electrode. The surface properties of the modified electrodes were characterized using scanning electron microscopy–energy dispersive spectroscopy and atomic force microscopy. The electrochemical performance of the modified electrodes was evaluated using cyclic voltammetry, electrochemical impedance spectroscopy, and differential pulse voltammetry. The bimetallic Au-Ag …

Development Of Shigella Flexneri Detection Method By Real-Time Polymerase Chain Reaction Targeting The Sfmd Gene, Muktiningsih Nurjayadi, Puan Aqila Azizah, Agus Setiawan, Ananda Indah Putri Sihombing, Anisa Fitriyanti, Grace Grace, Gusti Angieta Putri, Helzi Angelina, Royna Rahma Musie, Jefferson Lynford Declan, Gladys Indira Putri, Dandy Akbar Juliansyah, Siti Fatimah, Tiara Fahriza, Irma Ratna Kartika, Fera Kurniadewi, Novitasari Novitasari, Bassam Abomoelak, Hesham Ali El Enshasy, Shyi-Tien Chen

Makara Journal of Science

Shigella flexneri can cause shigellosis, which results in high fever, vomiting, diarrhea, or death. This study developed a detection method based on real-time polymerase chain reaction that targets the sfmD gene of S. flexneri given that the virulence factor encoded by this gene is thought to facilitate adhesion to a host surface. The proposed method involves primer design, DNA isolation, the optimization of primer annealing temperature, and confirmation, specificity, and sensitivity tests. A sfmD primer with an amplicon length of 155 bp was annealed to the target DNA at an optimized temperature of 60 ℃ (range 54 °C–62 °C). This …

Comparisons Of Zooplankton Communities Before And After Chemical Renovation In Lake Ogallala, Nebraska, Theo Huber, Melissa Wuellner, Alexandria Keiler-Klein, Alexander D. Engel, Keith D. Koupal

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Rotenone is commonly used to remove undesirable fish species and support recreational fisheries. Lake Ogallala, a 263-ha tailwater reservoir located in western Nebraska, has had a history with rotenone use dating back to 1969. While past renovations of the reservoir have documented impacts on water quality, aquatic vegetation establishment, and benthic invertebrate and fish communities, zooplankton responses had not been studied. To evaluate potential effects, we compared zooplankton densities and community composition before and after the most recent renovation. Monthly samples were collected from April – September in 2023 (pre-renovation) and 2024 (post-renovation) using an 80-μm circular plankton net at …