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Modelling Acute Haemorrhagic Conjunctivitis In East Africa: An Integrated Approach To Transmission Dynamics And Outbreak Response Strategies, Geofrey Wingi Sikazwe Sep 2026

Modelling Acute Haemorrhagic Conjunctivitis In East Africa: An Integrated Approach To Transmission Dynamics And Outbreak Response Strategies, Geofrey Wingi Sikazwe

Tanzania Journal of Science

Acute hemorrhagic conjunctivitis (AHC) poses a significant global health risk, with the potential for rapid spread during outbreaks. For instance, a localized outbreak in Yunnan Province, China, recorded infection rates of up to 48%, illustrating how transmission can intensify under favourable epidemiological and environmental conditions. Existing mathematical models of AHC transmission overlook seasonal variations, a critical factor in epidemic spread. This study combines species distribution models (SDMs) and epidemiological modelling to analyse key drivers of AHC in East Africa. We use the SEIR type (Susceptible-Exposed-Infected-Recovered - incorporating waning immunity) framework with temperature-dependent infectivity rate as the key driver of an …


Silicon Nitride Thin Film Deposited By Plasma-Enhanced Chemical Vapour Deposition Technique For Various Device Applications, Anayesu Bariki Malisa Sep 2026

Silicon Nitride Thin Film Deposited By Plasma-Enhanced Chemical Vapour Deposition Technique For Various Device Applications, Anayesu Bariki Malisa

Tanzania Journal of Science

This work reports on silicon nitride (SiNx) thin film deposited by the Plasma-Enhanced Chemical Vapour Deposition (PECVD) technique. The film was characterized by Variable Angle Spectroscopic Ellipsometry (VASE) to obtain optical constants 𝑛, 𝑘 and thickness using the Cauchy layer built on the Lorentz oscillator model and the B-spline model. The determined optical band gap 𝐸𝑜𝑝𝑡𝑖𝑐𝑎𝑙 for direct transition was 3.2 𝑒𝑉 and that for indirect transition was 2.13 𝑒𝑉. Film characterization was performed by Fourier Transform Infra-Red spectroscopy (FTIR) at two different angles of incidence of 15 degrees to probe deep layers and 65 degrees (Brewster’s angle) to excite …


Clustering Of Potable Water Sources In Rural Oyo State, Nigeria: Implications For Equitable Distribution And Sustainability, Adesola Adediran, Ibrahim O. Raufu Sep 2026

Clustering Of Potable Water Sources In Rural Oyo State, Nigeria: Implications For Equitable Distribution And Sustainability, Adesola Adediran, Ibrahim O. Raufu

Tanzania Journal of Science

Adequate and equitable access to potable water remains a major challenge in rural communities of Oyo State, Nigeria, with uncoordinated provision leading to widespread shortages. This study employs geospatial techniques to assess the spatial distribution of water supply sources across five purposively selected rural communities in Olorunsogo Local Government Area (OLGA). Geographic coordinates of boreholes, hand-dug wells, and other potable water sources were collected using a handheld Garmin GPS 76S device. Spatial analysis was conducted using ArcGIS, and Nearest Neighbour Analysis (NNA) was applied to evaluate the pattern of distribution. Results indicate a strong tendency toward clustering, with a Nearest …


A Data-Driven Neutrosophic Multi-Criteria Intelligent System For Functional Disability Severity Assessment, Ehab Abdel Aziz Al-Beblawi, Mirna Samy, Abduallah Gamal Sep 2026

A Data-Driven Neutrosophic Multi-Criteria Intelligent System For Functional Disability Severity Assessment, Ehab Abdel Aziz Al-Beblawi, Mirna Samy, Abduallah Gamal

Neutrosophic Systems with Applications

Functional disability assessment is a multidimensional problem because individuals may experience different levels of difficulty across daily activities such as walking, standing, dressing, eating, grasping objects, and social participation. This paper proposes NIFDA, a data-driven neutrosophic multi-criteria intelligent system for functional disability severity assessment. The proposed framework represents each functional response through three components: confirmed limitation, indeterminacy, and preserved functional ability. This allows the model to handle valid responses, uncertain information, and missing or non-informative data without forcing them into a single crisp score. To reduce dependence on subjective expert weighting, NIFDA derives criterion weights objectively using a hybrid CRITIC–MEREC …


A Neutrosophic Memory-Integrity Calculus For Contradiction-Preserving Persistent Ai Agents, Rana Muhammad Zulqarnain, Saalam Ali Sep 2026

A Neutrosophic Memory-Integrity Calculus For Contradiction-Preserving Persistent Ai Agents, Rana Muhammad Zulqarnain, Saalam Ali

Neutrosophic Systems with Applications

Persistent AI agents increasingly convert interaction histories into long-lived memory, making memory transformation not retrieval alone—a central reliability problem. NMIC (Neutrosophic Memory-Integrity Calculus) formalizes the integrity of write, merge, consolidation, revision, and retrieval operations over persistent memory. Each proposition is represented through an evidence ledger carrying independent truth, indeterminacy, and falsity degrees together with reliability, provenance, temporal validity, contextual applicability, and inter-evidence dependence. A dependence-normalized hazard aggregation preserves simultaneous support and opposition while making the resulting state invariant to exact evidence duplication. Pure consolidation is governed by five integrity conditions: no support invention, no opposition invention, no manufactured certainty, contradiction …


Decision Support System For The Selection Of Thumbprint Recognition Algorithms In Biometric Security Systems, Toqeer Jameel, Muhammad Riaz Sep 2026

Decision Support System For The Selection Of Thumbprint Recognition Algorithms In Biometric Security Systems, Toqeer Jameel, Muhammad Riaz

Neutrosophic Systems with Applications

This study investigates fingerprint recognition in immigration operations, emphasizing the role of biometric verification in enhancing security, fairness, and operational efficiency in international mobility. To address the uncertainty, vagueness, and imprecision inherent in fingerprint identification, a novel decision-making framework is proposed by integrating interval-valued picture fuzzy (IVPF) information. Fairly aggregation operators are introduced to combine decision makers' evaluations, while extracted fingerprint features are modeled using positive, neutral, and negative membership degrees within the IVPF environment. Objective criterion weights are determined using the criteria importance through intercriteria correlation (CRITIC) method, and individual ranking is performed via the alternative ranking order method …


Neutrosophic Indeterminacy-Transport Kolmogorov-Arnold Networks For Structured Uncertainty, Hafiz Muhammd Bilal, Kiran Naz, Anjum Ijaz Sep 2026

Neutrosophic Indeterminacy-Transport Kolmogorov-Arnold Networks For Structured Uncertainty, Hafiz Muhammd Bilal, Kiran Naz, Anjum Ijaz

Neutrosophic Systems with Applications

Kolmogorov-Arnold Networks (KANs) replace fixed node activations with learnable univariate edge functions, but standard KAN inference treats two equal-valued features identically even when one is accompanied by an explicit quality warning. NIT-KAN introduces a neutrosophic indeterminacy-transport mechanism for this setting. Each node carries an indeterminacy state in [0, 1]; a monotone gate g(I)=(1-I)α attenuates uncertain evidence on the predictive path, while a sensitivity-weighted transport rule carries indeterminacy through the underlying KAN computation. A terminal audit maps signed evidence to truth-support, falsity-support, and conflict-augmented indeterminacy without interpreting these quantities as class probabilities. We …


The Use Of Gadgets And Learning Motivation Among Grade Xi Students In Biology Learning At Sma Negeri 5 Palu, Yulia Citra, Mohammad Jamhari, Masrianih Masrianih, Lestari M.P Alibasyah, Mursito S. Bialangi, Yulia Windarsih Sep 2026

The Use Of Gadgets And Learning Motivation Among Grade Xi Students In Biology Learning At Sma Negeri 5 Palu, Yulia Citra, Mohammad Jamhari, Masrianih Masrianih, Lestari M.P Alibasyah, Mursito S. Bialangi, Yulia Windarsih

Jurnal Pendidikan Sains

This study aims to describe the profile of gadget use and learning motivation among Grade XI students in biology learning at SMA Negeri 5 Palu and to explore students’ and teachers’ experiences of gadgets as learning support tools and potential sources of digital distraction. A qualitative descriptive design was employed, supported by descriptive questionnaire profiling. A total of 74 students completed a 50-item questionnaire on gadget use and learning motivation, while 10 students and two biology teachers participated in semi-structured interviews. Questionnaire data were analyzed using frequencies and percentages, while interview data were analyzed thematically. The descriptive findings showed that …


The Application Of The Group Investigation (Gi) Model Of Cooperative Learning To Improve Students’ Understanding Of Biodiversity In Year 10 At Sman 2 Mori Atas, Nadia Rosmita Lumako, Mohammad Jamhari, Yulia Windarsih, Lilies Lilies, Rafiqa Rafiqa, Amalia Buntu Sep 2026

The Application Of The Group Investigation (Gi) Model Of Cooperative Learning To Improve Students’ Understanding Of Biodiversity In Year 10 At Sman 2 Mori Atas, Nadia Rosmita Lumako, Mohammad Jamhari, Yulia Windarsih, Lilies Lilies, Rafiqa Rafiqa, Amalia Buntu

Jurnal Pendidikan Sains

Biology instruction at SMAN 2 Mori Atas was predominantly conducted through conventional teaching practices. Preliminary observations revealed that students had difficulty understanding biodiversity concepts, and several students did not meet the minimum passing criterion of 70. These conditions highlighted the need for learning activities that promote active investigation, discussion, and conceptual connections. This classroom action research examined the use of the Group Investigation (GI) cooperative learning model to improve Grade 10 students’ classroom engagement and conceptual understanding of biodiversity, as assessed through Higher-Order Thinking Skills (HOTS) questions based on the Structure of Observed Learning Outcomes (SOLO) taxonomy. The study involved …


The Effect Of The Problem-Based Learning Model On Biology Learning Outcomes In The 8th Grade Science Class At Smp Negeri 19 Palu, Delfi Srieviyani, Mursito S. Bialangi, Masrianih Masrianih, Abd Hakim Laenggeng, Vita Indri Febriani, Bustamin Bustamin Sep 2026

The Effect Of The Problem-Based Learning Model On Biology Learning Outcomes In The 8th Grade Science Class At Smp Negeri 19 Palu, Delfi Srieviyani, Mursito S. Bialangi, Masrianih Masrianih, Abd Hakim Laenggeng, Vita Indri Febriani, Bustamin Bustamin

Jurnal Pendidikan Sains

Research background: The low student achievement in biology at SMP Negeri 19 Palu specifically regarding the human respiratory system is attributed to the conventional teaching methods still employed by teachers. Purpose and scope of the article: This study examines the effect of the Problem-Based Learning (PBL) model on students’ learning outcomes in biology, specifically regarding the human respiratory system. Method: This study used a quasi-experimental design with a quantitative approach. The research design employed was a nonequivalent control group design using two groups: an experimental group (Class VIII D) consisting of 25 students who received the PBL model, and a …


Evaluation Of Carcinogenic Contaminants (Nitrates, Ammonium, Bromates, And Chloroform) In Baghdad Drinking Water And Their Removal Using Orange Peel Powder As A Bio Sorbent, Estabraq Ali Hameed, Hiba N. Sami, Eman Waleed Hayder Sep 2026

Evaluation Of Carcinogenic Contaminants (Nitrates, Ammonium, Bromates, And Chloroform) In Baghdad Drinking Water And Their Removal Using Orange Peel Powder As A Bio Sorbent, Estabraq Ali Hameed, Hiba N. Sami, Eman Waleed Hayder

Karbala International Journal of Modern Science

The present study was carried out for six months to detect the presence of some important chemical contaminants (bromate, nitrate, chloroform, and ammonium) in the drinking water of Baghdad at ten sampling sites. The study suggested the use of orange peel powder (OPP) as a cheap and eco-friendly biosorbent. X-ray diffraction (XRD) was used to confirm the amorphous nature, surface and structural characteristics of OPP. Further, SEM investigation also showed very microporous surface. FTIR (Fourier Transform Infra-Red Spectroscopy) analysis confirmed the presence of active carboxyl (-COOH) and hydroxyl (-OH) binding sites. Baseline studies show that the levels of nitrate and …


Age Differences In Perceived Individual And Community Recovery After Tornadoes: Implications For Community-Centered Recovery Policy In An Aging Society, Sizhuo Chen, Zhen Cong Sep 2026

Age Differences In Perceived Individual And Community Recovery After Tornadoes: Implications For Community-Centered Recovery Policy In An Aging Society, Sizhuo Chen, Zhen Cong

Health Sciences and Kinesiology Faculty Articles

"This study examines perceived individual recovery and perceived community recovery among tornado survivors across three waves spanning four years. Using three-wave longitudinal survey data from survivors in Dallas, Texas; Nashville, Tennessee; and Birmingham, Alabama collected in 2021, 2022, and 2025, we estimate recovery trajectories using linear mixed-effects growth models. We link respondents to tract-level SVI 2020 component measures to examine whether tract-level social vulnerability contextualizes age differences in recovery perceptions. We ask: (1) How do perceived individual recovery and perceived community recovery change over time? (2) Do these trajectories differ by age group? (3) Do community social vulnerability measures contextualize …


Nontarget Analysis Of The Volatile And Semivolatile Chemical Profile Of Wildland Firefighter Gear: Insight Into Occupational Exposure And Health Implications, Patrica Ivy Agorsor, Husam Kafeenah, Margaret D. Taiwo, Robin M. Verble, Michael O. Eze Sep 2026

Nontarget Analysis Of The Volatile And Semivolatile Chemical Profile Of Wildland Firefighter Gear: Insight Into Occupational Exposure And Health Implications, Patrica Ivy Agorsor, Husam Kafeenah, Margaret D. Taiwo, Robin M. Verble, Michael O. Eze

Biological Sciences Faculty Research & Creative Works

Prescribed fire releases a complex mixture of volatile and semivolatile organic compounds to the environment. Firefighters are directly exposed to these hazardous mixtures through occupational activities. This study investigated the volatile and semivolatile chemical contamination profile of firefighter protective gear and the effectiveness of laundering as a decontamination strategy. Our results revealed that firefighter gear accumulated a broad spectrum of combustion-derived contaminants, predominantly composed of polycyclic aromatic hydrocarbons and derivatives, phenolic compounds, and aromatic hydrocarbons. Representative compounds identified included toluene, biphenyl, naphthalene, 1-methynaphthalene, 2-methylnaphthalene, acenaphthene, phenol, alkylated phenols, and chlorinated phenols. Quantitative analysis revealed representative combustion-derived compounds at concentrations (mean …


Enhancing Visitor Experiences Through Storytelling In Interpretive Tour Guiding, Naoko Yamada Sep 2026

Enhancing Visitor Experiences Through Storytelling In Interpretive Tour Guiding, Naoko Yamada

International Journal of Tour Guiding and Visitor Attraction Research

Heritage interpretation enables visitors to make sense of their experiences by communicating meaningful messages at natural and cultural heritage sites. By fostering understanding, appreciation, and personal relevance, interpretation enriches visitor experiences and encourages responsible attitudes and behaviors. Among various interpretive approaches, storytelling has emerged as a particularly promising means of achieving these outcomes. However, research examining how storytelling enriches heritage interpretation and promotes deeper visitor engagement remains limited. This conceptual paper synthesizes literature from storytelling, psychology, marketing, tourism, and heritage interpretation to develop a framework explaining how storytelling influences interpretive outcomes. The framework proposes that story elements activate psychological mechanisms, …


Understanding The Role Of Data Science Applications In Soil And Water Health, Payton Davis, Debabrata Sahoo, Dara Park, Brook Russell Sep 2026

Understanding The Role Of Data Science Applications In Soil And Water Health, Payton Davis, Debabrata Sahoo, Dara Park, Brook Russell

Forestry and Natural Resources

Data science is an emerging field that can be incorporated into many disciplines, including environmental science. Data science can provide valuable information from data, enhancing the understanding of systems and environments. This publication is intended to give an overview of the different aspects of data science and how data science can be leveraged into and applied to soil and water health.


Generalized Apostol-Bernoulli Functions And The Evaluation Of Character Sums, Brad Isaacson Sep 2026

Generalized Apostol-Bernoulli Functions And The Evaluation Of Character Sums, Brad Isaacson

Publications and Research

We introduce two types of generalized Apostol–Bernoulli functions attached to Dirichlet characters and express them by generalized Apostol–Bernoulli numbers. As a corollary, we obtain formulas expressing two families of character sums by generalized Apostol–Bernoulli numbers. These sums are twisted generalizations of sums introduced and studied by Arakawa, Berndt, Ibukiyama, Kaneko, Kim, Ramanujan, and Zaharescu in the context of modular forms and theta function identities.


Efficient Acidic H2O2 Electrosynthesis Over Co Atoms Anchored On Nitrogen-Doped Hierarchical Porous Carbon, Xiao Huang, Zi-Hao Zhan, Hao-Xu Niu, Guan-Yu Luo, Jin-Tao Huang, Bo-Xuan Jin, De-Li Wang Sep 2026

Efficient Acidic H2O2 Electrosynthesis Over Co Atoms Anchored On Nitrogen-Doped Hierarchical Porous Carbon, Xiao Huang, Zi-Hao Zhan, Hao-Xu Niu, Guan-Yu Luo, Jin-Tao Huang, Bo-Xuan Jin, De-Li Wang

Journal of Electrochemistry

The two-electron oxygen reduction reaction (2e− ORR) presents a promising route for the on-site production of hydrogen peroxide (H2O2), offering a green alternative to energy-consuming anthraquinone process. However, the high selectivity toward the competing 4e− ORR over the desired 2e− pathway leads to low Faradaic efficiency for H2O2, posing a critical challenge in catalyst design. In this work, a nitrogen-doped hollow hierarchical porous carbon with anchored Co atoms (CoN/HPC) was constructed for high-performance H2O2 production. The as-prepared Co-N/HPC catalyst showed excellent 2e− ORR performance, achieving …


Engineering Small-Sized Cations With Strong Solvation For High-Voltage Supercapacitors, Tong Huo, Pan Liu, Hao Chen, Peng Zhang, Zhen-Lei Chen, Guo-Fu Sun, Zhi-Qiang Shi, Jing Wang Sep 2026

Engineering Small-Sized Cations With Strong Solvation For High-Voltage Supercapacitors, Tong Huo, Pan Liu, Hao Chen, Peng Zhang, Zhen-Lei Chen, Guo-Fu Sun, Zhi-Qiang Shi, Jing Wang

Journal of Electrochemistry

Supercapacitors (SCs) have attracted much attention in the field of energy storage due to their high power density and long cycle life. However, their relatively low energy density limits their application in a wider range of fields. Methods to increase energy density include enhancing specific capacitance and extending operating voltage window. Herein, we report a novel electrolyte salt, tetramethylammonium bis(fluorosulfonyl)imide (TMA-FSI), the resulting electrolyte formed with propylene carbonate (PC), designated as TMF, exhibited a wide electrochemical stability window (ESW) of 5.09 V. On the one hand, we found that the small size of TMA+ enables it to enter the …


Oco-3 Meets Ecostress: Insights Into Ecosystem Diurnal Water-Use Efficiency From Co-Located Solar-Induced Fluorescence And Thermal Observations, Zoe Amie Pierrat, Thomas P. Kurosu, Abhishek Chatterjee, Joshua B. Fisher, Maggie Johnson, Le Kuai, Kanishka Mallick, Nicholas Parazoo, Benjamin Wiebe, Kerry Cawse-Nicholson Sep 2026

Oco-3 Meets Ecostress: Insights Into Ecosystem Diurnal Water-Use Efficiency From Co-Located Solar-Induced Fluorescence And Thermal Observations, Zoe Amie Pierrat, Thomas P. Kurosu, Abhishek Chatterjee, Joshua B. Fisher, Maggie Johnson, Le Kuai, Kanishka Mallick, Nicholas Parazoo, Benjamin Wiebe, Kerry Cawse-Nicholson

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Terrestrial ecosystem regulation of carbon and water fluxes is critical for constraining climate–biosphere feedbacks but remains poorly quantified across space and time. Here, we evaluate whether co-located observations from NASA's Orbiting Carbon Observatory-3 (OCO-3) and the ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS) can reproduce ecosystem water use efficiency (WUE) dynamics observed at FLUXNET sites across temporal scales, vegetation types, climates, and drought conditions. We created the ECOCO3 data set, which harmonizes OCO-3 and ECOSTRESS observations in space and time. ECOCO3 captures broad seasonal and diurnal carbon and water flux patterns including midday drought responses. Sampling sensitivity analysis …


Dense Platinum Nanoparticles Confined In Mn-N-C Nanocages For Robust Heavy-Duty Pemfcs, Lei Zhao, Zhen-Min Cao, Jia-Yu Zuo, Ming-Liang Yang, Hong-Yan Qiao, Jun-Song Chen, Rui Wu Sep 2026

Dense Platinum Nanoparticles Confined In Mn-N-C Nanocages For Robust Heavy-Duty Pemfcs, Lei Zhao, Zhen-Min Cao, Jia-Yu Zuo, Ming-Liang Yang, Hong-Yan Qiao, Jun-Song Chen, Rui Wu

Journal of Electrochemistry

High-loading Pt cathodes are essential for heavy-duty proton exchange membrane fuel cells but suffer from a critical tradeoff between ionomer sulfonate poisoning and nanoparticle instability. Herein, we report a spatial confinement strategy to encapsulate dense Pt nanoparticles (~51.8 wt%) within Mn/N-co-doped mesoporous carbon nanocages (denoted as Pt-MnNC). This architecture excludes bulky ionomers to create an ionomer-shielded environment against sulfonate poisoning, while Mn-Nx-mediated strong metal-support interactions anchor the Pt nanoparticles to prevent agglomeration and further boost durability. In the 5 × 5 cm2 membrane electrode assembly tests, the Pt-MnNC catalyst delivers an exceptional power density of 1.26 W·cm …


Chacahoula 2026, Volume 93, Pawan Khatri, Alayna Pellegrin Sep 2026

Chacahoula 2026, Volume 93, Pawan Khatri, Alayna Pellegrin

Chacahoula

The 2026 issue of Chacahoula, There's No Place Like Home, emphasizes the way in which our university becomes a home to students.  Featuring prize-winning poetry from Allyson Gee, Nick Fredrick, Amaris Kendall and Anmol Subedi, the book includes December 2025 and May 2026 graduating classes, as well as stunning photography of  campus life on the banks of Bayou Desiard. With features covering students, faculty, and staff, this year's time capsule preserves an academic year in the life of the University of Louisiana at Monroe. This edition includes a video message from President Carrie Castille. Download the PDF to your device …


Characterization Of Combined Adsorption Using Fermi Levels, Molecular Dynamics, And Monte Carlo Simulations To Prevent Cu–Zn (111) Alloy Corrosion, Mushtaq Jerri Meften, Ammar Abdul Jabbar Kadhim, Mohammed Shafeeq Abed Sep 2026

Characterization Of Combined Adsorption Using Fermi Levels, Molecular Dynamics, And Monte Carlo Simulations To Prevent Cu–Zn (111) Alloy Corrosion, Mushtaq Jerri Meften, Ammar Abdul Jabbar Kadhim, Mohammed Shafeeq Abed

Makara Journal of Science

Experimentally developing corrosion inhibitors requires a significant amount of money and time. In silico advancement empowers selecting inhibitor molecules based on their properties derived from theoretical studies, thereby reducing costs. Our main approaches include theoretical studies such as Fermi levels, electrostatic potential surface (EPS), Fukui indices, molecular dynamics stimulations, and Monte Carlo as indispensable tools to investigate the adsorption mechanisms of molecules 6-((5-(((3S,5R)-2-oxo-5-((2-(pyrazin-2-yloxy) thiazol-5-yl) thio) tetrahydro-2H-thiopyran-3-yl) oxy)isothia-zol-3-yl)thio) nicotinic acid (PTT), and (S)-2-((5-((6-((3-(2-thioxoethoxy)-1,2,4-thiadiazol-5-yl)thio)-1,6-dihydropyra-zin-2-yl)oxy)-1,3,4-thiadiazol-2-yl) thio) acetaldehyde (TTD) on the Cu/Zn (111) alloy. We electronically characterized PTT and TTD, which were proven effective inhibitors. Notably, all results suggested that the two exhibited high …


Increasing The Density Value Of Composite Propellant Ap/Htpb/Al For Rocket Performance Using The Sphere Packing Model, Muhammad Iqbal Alfikri, Bayu Prianto, Ariadne Lakshmidevi Juwono Sep 2026

Increasing The Density Value Of Composite Propellant Ap/Htpb/Al For Rocket Performance Using The Sphere Packing Model, Muhammad Iqbal Alfikri, Bayu Prianto, Ariadne Lakshmidevi Juwono

Makara Journal of Science

This research employs the sphere packing volume (SPV) model to optimize the density of composite propellants thereby enhancing rocket performance. We systematically varied the diameters of spherical ammonium perchlorate (AP) particles (50 and 400 µm) and aluminum powder (Al) particles (10 and 30 µm). These particles were incorporated at an ideal AP:Al ratio of 4:1 into a matrix of hydroxyl-terminated polybutadiene and toluene diisocyanate. By adjusting the AP ratio for each Al particle size and considering theoretical and tap densities, we precisely calculated the SPV value for each composition. The composition with the highest SPV value yielded remarkable results. This …


Impact Of Disturbances On Butterfly Communities At The Forest Edge Of Bukit Mas Village, North Sumatra, Indonesia, Nurhayati Nurhayati, Mufti Petala Patria, Nurul Winarni, Fairuz Husna Sep 2026

Impact Of Disturbances On Butterfly Communities At The Forest Edge Of Bukit Mas Village, North Sumatra, Indonesia, Nurhayati Nurhayati, Mufti Petala Patria, Nurul Winarni, Fairuz Husna

Makara Journal of Science

Biotic homogenization can negatively impact ecosystem function and stability, reducing species diversity and interac-tions. Although deforestation has declined in Gunung Leuser National Park since 2011, associated pressures still operate at various places within the park, possibly leading to biotic homogenization. This study looked into the differences in butterfly diversity under three habitat types to understand their responses to various levels of disturbance, including en-vironmental factors. This research was carried out in September 2023 at the forest edge of the Bukit Mas Village, North Sumatra. We used the Point Count method; observations were made twice in the morning (08.00–12.00 h) and …


Lignin Valorization To Phenolic Compounds Over Metal Oxide-Modified Hierarchical Zsm-5 Zeolites Derived From Indonesian Minerals, Arnia Putri Pratama, Iman Abdullah, Yuni Krisyuningsih Krisnandi Sep 2026

Lignin Valorization To Phenolic Compounds Over Metal Oxide-Modified Hierarchical Zsm-5 Zeolites Derived From Indonesian Minerals, Arnia Putri Pratama, Iman Abdullah, Yuni Krisyuningsih Krisnandi

Makara Journal of Science

Lignin, a key component of lignocellulosic biomass, offers significant potential as a renewable raw material for the sustainable production of aromatic chemicals. To investigate its heterogeneous catalytic depolymerization, benzyl phenyl ether (BPE) was used as a model compound. Hierarchical ZSM-5 catalysts were synthesized and modified with metal oxides (NiO and CuO). Belitung kaolin and Bayat natural zeolite, natural minerals from Indonesia, were used as silica and alumina sources to synthesize hierarchical ZSM-5 zeolite (labeled as ZSM-5N), which was compared with hierarchical ZSM-5 synthesized using pro-analysis precursors (labeled as ZSM-5S). Comprehensive physicochemical characterization using FTIR, XRD, BET, XRF, SEM-EDX, and NH₃-TPD …


Evaluating Peak Metamorphic Conditions Of The Kyanite-Bearing Rocks At Willis Mountain, Virginia, Usa, Emma J. Hunt, Peter Horvath, Connor R. Gregory, Jade D. Sabillon, Ethan H. Watson Sep 2026

Evaluating Peak Metamorphic Conditions Of The Kyanite-Bearing Rocks At Willis Mountain, Virginia, Usa, Emma J. Hunt, Peter Horvath, Connor R. Gregory, Jade D. Sabillon, Ethan H. Watson

Earth and Environmental Sciences Publications

Willis Mountain, near Dillwyn in central Virginia, is the world’s largest kyanite deposit located in the Chopawamsic Fm. of the Piedmont province. However, little is known about the temperature and pressure conditions under which the kyanite deposit and its surrounding rocks formed, compared with similar-aged rocks in the Blue Ridge province to the southwest. Willis Mountain is composed of kyanite-bearing muscovite schists to kyanite quartzites which contain up to 55% kyanite. The following methods were used to evaluate the metamorphic conditions, with multiple calibrations for each: phase equilibrium modelling; trace element thermometry (titanium in quartz and zirconium in rutile); garnet-biotite …


Home On The Range: Where Deer And Antelope Compete With Feral Horses For Limited Resources, Katelyn Davies, Hannah B. Klugman, Kathryn A. Schoenecker, David C. Stoner Sep 2026

Home On The Range: Where Deer And Antelope Compete With Feral Horses For Limited Resources, Katelyn Davies, Hannah B. Klugman, Kathryn A. Schoenecker, David C. Stoner

All Current Publications

Given projections for continued drought conditions in the West, a better understanding of how native wildlife respond to competition with feral horses will be critical for developing effective conservation programs in the future. This fact sheet provides information on feral horses and presents study data comparing their use of water resources with that of native wildlife.


Geotechnical Enhancement Of Noncohesive Coal Mine Overburden Using Microbially Induced Calcite Precipitation And Fly Ash Stabilization For Sustainable Pavement Applications, Atul Gautam, Laxmikant Yadu Sep 2026

Geotechnical Enhancement Of Noncohesive Coal Mine Overburden Using Microbially Induced Calcite Precipitation And Fly Ash Stabilization For Sustainable Pavement Applications, Atul Gautam, Laxmikant Yadu

Journal of Sustainable Mining

The majority of the waste generated from opencast mining, termed as overburden (OB), is dumped adjacent to the mine boundary and poses long-term stability issues. Various studies have been carried out to assess the risk of dump slope failure, and treatment strategies have been accordingly recommended to strengthen this OB dump. However, scant works are reported to sustainably utilize this OB for construction works. This study aims to quantify the performance of stabilized noncohesive coal mine OB collected from Gondegaon opencast mine (OCM) in India. Stabilization was achieved using two techniques, namely microbially induced calcite precipitation (MICP) through Sporosarcina pasteurii …


Evaluating Atmospheric Nox In The Marine Boundary Layer Near Tampa Bay, Ben Lloyd '25, Anson Kirsch, Samuel Irvine, Yasin Elshorbany, James Ivey Sep 2026

Evaluating Atmospheric Nox In The Marine Boundary Layer Near Tampa Bay, Ben Lloyd '25, Anson Kirsch, Samuel Irvine, Yasin Elshorbany, James Ivey

Student Research

Nitrogen oxides (NOX), including nitric oxide (NO) and nitrogen dioxide (NO₂), are atmospheric constituents that can contribute to nitrate deposition in seawater. Since nitrate availability can influence marine ecosystems, understanding atmospheric nitrogen inputs is important for characterizing nitrogen cycling in coastal environments. This dataset contains atmospheric NO and NO₂ measurements collected from July 5–6, 2023, in the marine boundary layer near Tampa Bay, Florida, at the University of South Florida St. Petersburg campus using a Teledyne T200UP Analyzer.

The dataset provides observations of atmospheric nitrogen oxide concentrations that can be compared with measurements of nitrate in rainwater and seawater to …


When Three Points Aren't Enough: Parameter Estimation In Newton's Law Of Cooling, Alberto A. Condori, Cara D. Brooks, Madeline R. Goldberg Sep 2026

When Three Points Aren't Enough: Parameter Estimation In Newton's Law Of Cooling, Alberto A. Condori, Cara D. Brooks, Madeline R. Goldberg

CODEE Journal

We begin with a paradoxical three-point problem where the standard parameter estimation formula fails because temperature data must satisfy a concavity condition reflecting Newton's Law of Cooling's exponential structure. Although a closed-form solution for A exists for equally-spaced measurements, high sensitivity to error motivates the use of overdetermined systems with many measurements. The "profiling over A" technique transforms this three-parameter nonlinear problem into a sequence of simple linear regressions, providing computational efficiency and conceptual transparency. This approach can be generalized to many parameter estimation problems in science and engineering, making it a valuable tool for undergraduates interested in applied mathematics. …