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Synthesis And Characterization Of New Azo Dyes Derived From Acyclovir And Sulfamethoxazole And Study Their Biological Activity, Abdul Rahman Y. Wahoud, Thanaa Shriteh, Ali Yousef, Mohammad Mazen Kondakji Mar 2023

Synthesis And Characterization Of New Azo Dyes Derived From Acyclovir And Sulfamethoxazole And Study Their Biological Activity, Abdul Rahman Y. Wahoud, Thanaa Shriteh, Ali Yousef, Mohammad Mazen Kondakji

Hadhramout University Journal of Natural & Applied Sciences

In this research, two new azo dyes, 9-(2-Hydroxy-ethoxymethyl)-2-(2-hydroxy5nitrophenylazo)-1,9-dihydro-purin-6-one and 4-(2-Hydroxy-napHthalen-1-ylazo)-N-(5-methyl-isoxazol-3-yl)-benzenesulfonamide, derived from Acyclovir and Sulfamethoxazole was synthesized. The first dye synthesis was started by diazation of acyclovir, then combined with 4-nitrophenol activated with potassium hydroxide 10%, yielding 80%, and its purity was verified by thin layer chromatography (TLC). The second dye synthesis was started by diazation of Sulfamethoxazole then combined with β-naphthol activated with potassium hydroxide 10%, yielding 87%, and its purity was verified by thin layer chromatography (TLC). The identity of the resulting pigments was determined based on spectroscopic methods such as infrared spectroscopy, proton nuclear magnetic resonance spectrum …


Application Of Pinch Analysis For Energy Saving And Reducing Gas Emissions Based On Mathematical Model In The Hydrocracking Unit, Badiea S. Babaqi Mar 2023

Application Of Pinch Analysis For Energy Saving And Reducing Gas Emissions Based On Mathematical Model In The Hydrocracking Unit, Badiea S. Babaqi

Hadhramout University Journal of Natural & Applied Sciences

Pinch analysis approach of the heat exchanger network in the hydrocracking unit was carried out to save the energy consumption and reduce the gas emissions simultaneously. This method based on mathematical model of the hydrocracking unit for a heat exchanger network using LINGO program to achieve the minimization of environmental impacts and the reduction of energy cost. The presented energy demands for the heat exchanger network are 20.38 MMBtu/hr and 26.52 MMBtu/hr for heating and cooling loads, respectively. The current analysis shows a huge opportunity in order to decrease energy consumption of the hydrocracking process at a minimum temperature difference …


Synthesis, Characterization, And Cytotoxicity Studies Of A Copper(Ii) Complex With Vanillin 3-Ethyl-Thiosemcarbazone A Ligand, Novia Mann, Ifeoluwa Oyeyemi, Duaa R. Alajroush, Elizabeth A. Tonsel-White, Stephen J. Beebe, Alvin Holder Mar 2023

Synthesis, Characterization, And Cytotoxicity Studies Of A Copper(Ii) Complex With Vanillin 3-Ethyl-Thiosemcarbazone A Ligand, Novia Mann, Ifeoluwa Oyeyemi, Duaa R. Alajroush, Elizabeth A. Tonsel-White, Stephen J. Beebe, Alvin Holder

Undergraduate Research Symposium

Triple-negative breast cancer (TNBC) is one of the most aggressive and challenging breast cancer subtypes to treat, as these cancer cells lack three common receptors: estrogen, progesterone, and human epidermal growth factor receptor 2. The multiple oxidation states transition metals can occupy have made this narrowly explored group popular for anti-cancer research in recent decades. Furthermore, the success of cisplatin, which has platinum as a metal center, while being a cancer-fighting agent with serious side effects, has caused other metal centers to be investigated as possible alternatives as chemotherapeutic drugs. Copper, as a biologically essential metal, makes an attractive candidate …


Margalefidinium Polykrikoides Cyst Resuspension In The Lafayette River, A Sub-Tributary Of The Chesapeake Bay, Gabrielle Greaney, Eduardo Perez Vega, Katherine Crider, Dreux Chappell, Kimberly Powell, Richard Hale, Peter Bernhardt, Margaret Mulholland Mar 2023

Margalefidinium Polykrikoides Cyst Resuspension In The Lafayette River, A Sub-Tributary Of The Chesapeake Bay, Gabrielle Greaney, Eduardo Perez Vega, Katherine Crider, Dreux Chappell, Kimberly Powell, Richard Hale, Peter Bernhardt, Margaret Mulholland

Undergraduate Research Symposium

Harmful Algal Blooms are a collection of algae in a body of water that can cause serious environmental issues and health problems in both people and aquatic organisms. Dinoflagellates are microscopic, unicellular, and eukaryotic organisms that are well known for forming harmful algal blooms because of eutrophication. Coastal Virginia suffers from HABs in the Chesapeake Bay and its tributaries. A common species of dinoflagellate, known as Margalefidinium polykrikoides exists in the Chesapeake Bay. The purpose of this study is to determine if sediment resuspension produced by wind generated surface gravity waves cause cysts (dinoflagellate resting stages) to be suspended into …


Object-Oriented Creative Coding For Digital Art Students, Dale E. Parson Mar 2023

Object-Oriented Creative Coding For Digital Art Students, Dale E. Parson

Computer Science and Information Technology Faculty

An introductory course in creative graphical coding for both computer science and digital art majors need not be watered down. The availability of an excellent Java-based framework including an IDE, debugger, and high-level class and function library avoids potentially problematic mathematics and device-control demands by encapsulating them within the library. Students can add or modify a few lines of code and then run them from the IDE without explicit compilation steps or tool changes, immediately seeing the results of initial coding or bug fixes in the form of animated graphical objects. Incremental introduction of object-oriented mechanisms within the course such …


Regeneration Strategies And Forest Resilience To Changing Fire Regimes: Insights From A Goldilocks Model, Tanjona Ramiadantsoa, Zak Ratajczak, Monica G. Turner Mar 2023

Regeneration Strategies And Forest Resilience To Changing Fire Regimes: Insights From A Goldilocks Model, Tanjona Ramiadantsoa, Zak Ratajczak, Monica G. Turner

Aspen Bibliography

Disturbances are ubiquitous in ecological systems, and species have evolved a range of strategies to resist or rebound following disturbance. Understanding how the presence and complementarity of regeneration traits will affect community responses to disturbance is increasingly urgent as disturbance regimes shift beyond their historical ranges of variability. We define "disturbance niche" as a species' fitness across a range of disturbance sizes and frequencies that can reflect the fundamental or realized niche, that is, whether the species occurs alone or with other species. We developed a model of intermediate complexity (i.e., a Goldilocks model) to infer the disturbance niche. We …


Potential Effect Of Phlorotannins In Brown Algae For Antidiabetic Therapy: Molecular Docking Approach, Melani Sinastri Renagupita, Rahadianto Rahadianto, Efyluk Garianto, Herin Setianingsih Mar 2023

Potential Effect Of Phlorotannins In Brown Algae For Antidiabetic Therapy: Molecular Docking Approach, Melani Sinastri Renagupita, Rahadianto Rahadianto, Efyluk Garianto, Herin Setianingsih

Makara Journal of Science

This study aims to manifest the effect of the active compound phlorotannins in brown algae on decreasing insulin resistance by analyzing the predicted interaction between phlorotannins and protein tyrosine phosphatase 1B (PTP 1B) and estimating the pharmacokinetics and toxicity of the active compound for type 2 diabetes mellitus (DM) therapy. This type of research uses an in silico study to test the effect of using phlorotannins as an active compound in brown algae against PTP 1B inhibition. Starting from preparing materials, i.e., downloading the three-dimensional structure of phlorotannins via PubChem and PTP 1B via RSCB PDB (PDB 1A5Y), molecular docking …


Diketopiperazine Cyclo-(S-Pro-R-Leu) Produced By Periconia Pseudobyssoides K5 Isolated From Toona Sureni (Meliaceae) And Its Heme Polymerization Inhibition Activity, Azmi Azhari, Desi Harneti, Asri Peni Wulandari, Yeni Mulyani, Sari Purbaya, Aprilia Permata Sari, Galih Bayu Pratama, Unang Supratman, Yoshihito Shiono Mar 2023

Diketopiperazine Cyclo-(S-Pro-R-Leu) Produced By Periconia Pseudobyssoides K5 Isolated From Toona Sureni (Meliaceae) And Its Heme Polymerization Inhibition Activity, Azmi Azhari, Desi Harneti, Asri Peni Wulandari, Yeni Mulyani, Sari Purbaya, Aprilia Permata Sari, Galih Bayu Pratama, Unang Supratman, Yoshihito Shiono

Makara Journal of Science

Fungi endophytes are living microorganisms colonizing inside the internal tissue of a plant and provide ecological benefits for their host. Endophytes provide various metabolites for plant adaptation toward biotic and abiotic stresses and have tremendous pharmacological activities. Toona sureni (T. sureni) (Meliaceae) belongs to the Toona genera and is reported to have antimalarial activity. To determine the compounds produced by the endophytic fungus from this plant, we isolated a compound from Periconia pseudobyssoides (P. pseudobyssoides) K5 endophytes from the stem bark of T. sureni. Diketopiperazine cyclo-(S-Pro-R-Leu), a non-ribosomal peptide, was isolated from brown …


Carbon Dioxide-Induced Corrosion Of Aisi 4140 Steel In Acidified Artificial Geothermal Brine, Anawati Anawati, Rayhan Izzat, Riene Kaelamanda Pragitta, Rafli Ihsan Hernandi Mar 2023

Carbon Dioxide-Induced Corrosion Of Aisi 4140 Steel In Acidified Artificial Geothermal Brine, Anawati Anawati, Rayhan Izzat, Riene Kaelamanda Pragitta, Rafli Ihsan Hernandi

Makara Journal of Science

Carbon dioxide (CO2)-induced corrosion often occurs in the structural materials of geothermal industry. The presence of CO2 influences the formation of various corrosion products. This research investigates the effect of dissolved CO2 in acidic brines on the corrosion behavior of AISI 4140 steel at atmospheric pressure. The brines were the standard brine, Ca-free brine, and high-salinity brine. The corrosion behavior was studied using electrochemical and immersion tests. A cyclic polarization test showed that the corrosion rate was higher in dissolved CO2 brine than in non-CO2 brine, and an immersion test demonstrated a similar result. …


The Potency Of Citrus Aurantiifolia Swingle And Sea Salt Solution As A Cleansing Agent For Edible Bird’S Nests, Siti Gusti Ningrum, Adhitya Yoppy Ro Candra, Hana Cipka Pramuda Wardhani Mar 2023

The Potency Of Citrus Aurantiifolia Swingle And Sea Salt Solution As A Cleansing Agent For Edible Bird’S Nests, Siti Gusti Ningrum, Adhitya Yoppy Ro Candra, Hana Cipka Pramuda Wardhani

Makara Journal of Science

The present study aimed to evaluate the potency of Citrus aurantiifolia Swingle and sea salt solution as a promising cleansing agent for edible bird’s nests (EBNs). Ascorbic acid, sodium, and chloride analyses of the C. aurantiifolia Swingle and sea salt solution were conducted using HPLC, ICP-OES, and titrimetry, respectively. The characteristics of physical samples and hydrogen peroxide detection were examined in this study. The reduction activity of the Citrus aurantiifolia Swingle and sea salt solution on the nitrite of 120 white EBNs was studied. This nitrite reduction activity was compared with the available method (standard), drinking water method, 6% C. …


Enrichment Media Selection And Co-Culture Potential Among Exoelectrogen Bacteria Vary With Ecological Factors, Nur Syafira Khoirunnisa, Syaiful Anwar, Untung Sudadi, Dwi Andreas Santosa Mar 2023

Enrichment Media Selection And Co-Culture Potential Among Exoelectrogen Bacteria Vary With Ecological Factors, Nur Syafira Khoirunnisa, Syaiful Anwar, Untung Sudadi, Dwi Andreas Santosa

Makara Journal of Science

Staphylococcus saprophyticus ICBB 9554 and Citrobacter freundii ICBB 9763 are exoelectrogen bacteria applied as microbial fuel cells (MFC). We selected enrichment media for both these exoelectrogen bacteria, characterized their synergistic traits, and evaluated the growth conditions under different ecological factors. In this study, different enrichment media, such as those containing sugar, molasses, and palm sugar (2, 4, and 6% w/v) were tested for S. saprophyticus ICBB 9554. Meanwhile, technical sodium acetate (NaAc), commercial vinegar 25%, and cider vinegar (5, 10, and 15 mM acetate concentration) were tested for C. freundii ICBB 9763. Both the exoelectrogen bacteria were tested for the …


Modification Of Zeolite Made From Coal Fly Ash With Tio2: Effect Of Aging Time On Physical And Optical Properties, Linda Jati Kusumawardani, Ani Iryani, Ennita Lusiana Sinaga Mar 2023

Modification Of Zeolite Made From Coal Fly Ash With Tio2: Effect Of Aging Time On Physical And Optical Properties, Linda Jati Kusumawardani, Ani Iryani, Ennita Lusiana Sinaga

Makara Journal of Science

The high levels of metal oxides, SiO2, and Al2O3 give coal fly ash the potential for development into zeolite. Zeolite was prepared from fly ash by combining alkaline fusion with hydrothermal treatment. Using this method results in a high surface area, high mechanical properties, and high crystallinity of the sample. Zeolite as a product is modified by TiO2. This study was intended to determine the effect of the operating process in zeolite synthesis from coal fly ash on the types and properties of zeolite and the effect of the aging time of TiO …


Synthesis And Study Of Anticancer And Antioxidant Activities Of 2-Oxoquinoline Hydrazide Derivatives, Marwa Khalil Mohamed, Ezzeldin Mohamed S. Salem, Ibrahim Ahmed I. Ali Mar 2023

Synthesis And Study Of Anticancer And Antioxidant Activities Of 2-Oxoquinoline Hydrazide Derivatives, Marwa Khalil Mohamed, Ezzeldin Mohamed S. Salem, Ibrahim Ahmed I. Ali

Makara Journal of Science

In this work, hydrazone, thiosemicarbazide, diamide, and dipeptide derivatives were prepared from the glycine and β-alanine hydrazide of 4-hydroxy-2-oxoquinoline. The desired derivative resulted from substitution, hydrazinolysis, condensation, and azide coupling reactions. The fabricated derivatives were screened for anticancer characteristics toward human’s colon carcinoma (HCT-116) cell line using the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide viability assay, while antioxidant property was examined using an in vitro H2O2 scavenging method. The β-alanine hydrazide derivative 3a showed a remarkable IC50 value of 18.8 μg/mL, whereas its corresponding thiosemicarbazide 5b exhibited moderate activeness with an IC50 value of 26.89 μg/mL. Conversely, …


Pva-Sansevieria Trifasciata Fraction Films As Absorbers Of Electromagnetic And Thermal Radiation On Smartphones, Nabiila Rahmani, Gustini Syahbirin, Akhiruddin Maddu, Purwantiningsih Sugita, Auliya Ilmiawati Mar 2023

Pva-Sansevieria Trifasciata Fraction Films As Absorbers Of Electromagnetic And Thermal Radiation On Smartphones, Nabiila Rahmani, Gustini Syahbirin, Akhiruddin Maddu, Purwantiningsih Sugita, Auliya Ilmiawati

Makara Journal of Science

Technological developments have prompted the production of highly advanced smartphones. However, various advanced features cause smartphones to heat up quickly and emit more electromagnetic radiation, which harms human health. Smartphone protection is needed to solve these issues. This study aims to create a film from the S. trifasciata plant based on polyvinyl alcohol (PVA) to reduce electromagnetic and thermal radiation on smartphones. S. trifasciata plants were macerated with acetone and partitioned with n-hexane, dichloromethane, ethyl acetate, and water. The films were made by mixing PVA with the four fractions. Among the four layers of film, the PVA + water …


Pvpbc: Privacy- And Verifiability-Preserving E-Voting Based On Permissioned Blockchain, Muntadher Sallal, Ruairí De Fréin, Ali Malik Mar 2023

Pvpbc: Privacy- And Verifiability-Preserving E-Voting Based On Permissioned Blockchain, Muntadher Sallal, Ruairí De Fréin, Ali Malik

Articles

Privacy and verifiability are crucial security requirements in e-voting systems and combining them is considered to be a challenge given that they seem to be contradictory. On one hand, privacy means that cast votes cannot be traced to the corresponding voters. On the other hand, linkability of voters and their votes is a requirement of verifiability which has the consequence that a voter is able to check their vote in the election result. These two contradictory features can be addressed by adopting privacy-preserving cryptographic primitives, which at the same time as achieving privacy, achieve verifiability. Many end-to-end schemes that support …


Expressed Willingness Of Stem Teachers To Teach Engineering, Zerrin Doganca Kucuk, Selvet Ece Genek, Hayriye Sinem Bozoglu, M. Sencer Corlu Mar 2023

Expressed Willingness Of Stem Teachers To Teach Engineering, Zerrin Doganca Kucuk, Selvet Ece Genek, Hayriye Sinem Bozoglu, M. Sencer Corlu

Journal of Pre-College Engineering Education Research (J-PEER)

Teaching engineering at the middle and high school levels has been a topic of discussion among scholars regarding the challenges it creates. One of the most critical challenges at the school level is identifying qualified teaching staff to lead engineering courses. The present study explored teachers’ willingness to lead an engineering course and the reasons behind their willingness or unwillingness to do so. The study involved 434 participants, who were enrolled in a STEM professional development program and were diverse regarding their teaching subjects, the grade levels they taught, and the locations of their schools in Turkey. In this mixed-methods …


Understanding The Impact Of Professional Development For A Cohort Of Teachers With Varying Prior Engineering Teaching Experience, Jennifer Kouo, Medha Dalal, Eunsil Lee, Bruk Berhane, Olushola Emiola-Owolabi, Jumoke Ladeji-Osias, Cheryl Beauchamp, Ken Reid, Stacy Klein-Gardner, Adam Carberry Mar 2023

Understanding The Impact Of Professional Development For A Cohort Of Teachers With Varying Prior Engineering Teaching Experience, Jennifer Kouo, Medha Dalal, Eunsil Lee, Bruk Berhane, Olushola Emiola-Owolabi, Jumoke Ladeji-Osias, Cheryl Beauchamp, Ken Reid, Stacy Klein-Gardner, Adam Carberry

Journal of Pre-College Engineering Education Research (J-PEER)

Engineering for US All (e4usa) is a National Science Foundation-funded first-of-its-kind initiative aimed at making engineering more inclusive and accessible to underrepresented populations. The ‘‘for us all’’ mission of e4usa encompasses both students and teachers. Paramount to the success of e4usa was the construction of professional development (PD) experiences to prepare and support teachers with different levels of engineering teaching experience as they implemented the e4usa yearlong course. The perspectives of nine teachers with varying degrees of engineering teaching experience were examined during two PD opportunities to compare experiences and dynamics between the teachers. Data sources consisting of focus groups …


Perception On The Use & Impact Of Facebook & Whatsapp For Academic Information By Undergraduate Students, Habibat O. Ochepa Cln Mar 2023

Perception On The Use & Impact Of Facebook & Whatsapp For Academic Information By Undergraduate Students, Habibat O. Ochepa Cln

Library Philosophy and Practice (e-journal)

Facebook and WhatsApp are social network platforms that have enhanced communication, Information sharing, and absorption, They are tools for social change and Knowledge assimilation their importance cannot be overemphasized which necessitate this study to investigate the perception of use and impacts of Facebook and WhatsApp for academic information for undergraduate students in Nigeria. The study uses Purposive sampling in selection of two universities situated in Abuja Municipal, one private and one public university, The research design adopted for this study was the descriptive survey research design with total enumeration of 2,010 undergraduate students from six departments (building, architecture, information technology, …


Using California Harmful Algae Risk Mapping To Predict Sea Lion Strandings, Florybeth La Valle, Sydney Socquet Mar 2023

Using California Harmful Algae Risk Mapping To Predict Sea Lion Strandings, Florybeth La Valle, Sydney Socquet

Seaver College Research And Scholarly Achievement Symposium

Domoic acid (DA) is a toxin produced by marine diatoms of the genus Pseudo-nitzschia (Pn) and bioaccumulates in California sea lions (Zalophus californianus). DA toxicosis can cause neurological issues and death, and the rate at which Z. californianus become stranded due to this condition has been increasing since it was first diagnosed in a marine mammal in 1998. We compared geotemporal data of sea lion strandings with data from the California Harmful Algae Risk Mapping (C-HARM) Model to analyze patterns that may indicate when and where a sea lion stranding due to DA toxicosis will occur. C-HARM geographically visualizes the …


Deep Learning Can Be Used To Classify And Segment Plant Cell Types In Xylem Tissue, Sean Wu, Reem Al Dabagh, Fabien Scalzo, Helen Irene Holmlund Mar 2023

Deep Learning Can Be Used To Classify And Segment Plant Cell Types In Xylem Tissue, Sean Wu, Reem Al Dabagh, Fabien Scalzo, Helen Irene Holmlund

Seaver College Research And Scholarly Achievement Symposium

Studies of plant anatomical traits are essential for understanding plant physiological adaptations to stressful environments. For example, shrubs in the chaparral ecosystem of southern California have adapted various xylem anatomical traits that help them survive drought and freezing. Previous studies have shown that xylem conduits with a narrow diameter allows certain chaparral shrub species to survive temperatures as low as -12 C. Other studies have shown that increased cell wall thickness of fibers surrounding xylem vessels improves resistance to water stress-induced embolism formation. Historically, these studies on xylem anatomical traits have relied on hand measurements of cells in light micrographs, …


Quantitation Of Female Newt Tetrodotoxin Concentrations And Their Impact In The Newt-Garter Snake Evolutionary Arms Race, Anna Frey, David Green Dr., Lee Kats Dr., Gary Bucciarelli Dr. Mar 2023

Quantitation Of Female Newt Tetrodotoxin Concentrations And Their Impact In The Newt-Garter Snake Evolutionary Arms Race, Anna Frey, David Green Dr., Lee Kats Dr., Gary Bucciarelli Dr.

Seaver College Research And Scholarly Achievement Symposium

As this work is not yet published, the authors have requested the removal of the abstract.


Pollen-Mediated Gene Flow From Genetically Modified Herbicide Resistant Creeping Bentgrass, L. S. Watrud, E. H. Lee, A. Fairbrother, C. Burdick, J. R. Reichman, M. Bollman, M. Storm, G. King, P. K. Van De Water Mar 2023

Pollen-Mediated Gene Flow From Genetically Modified Herbicide Resistant Creeping Bentgrass, L. S. Watrud, E. H. Lee, A. Fairbrother, C. Burdick, J. R. Reichman, M. Bollman, M. Storm, G. King, P. K. Van De Water

IGC Proceedings (1977-2023)

Approximately 162 ha of multiple experimental fields of creeping bentgrass (Agrostis stolonifera L.) genetically modified for resistance to Roundup ®herbicide, were planted in central Oregon in 2002. When the fields flowered for the first time in the summer of 2003, a unique opportunity was presented to evaluate methods to monitor potential pollen-mediated gene flow from the experimental GM crop fields to compatible sentinel and resident plants that were located in surrounding, primarily non-agronomic areas.


Assessing The Risk Posed By Transgenic Virus-Resistant Trifolium Repens To Native Grasslands In Southeast Australia, R. C. Godfree, P. W. G. Chu, A. G. Young Mar 2023

Assessing The Risk Posed By Transgenic Virus-Resistant Trifolium Repens To Native Grasslands In Southeast Australia, R. C. Godfree, P. W. G. Chu, A. G. Young

IGC Proceedings (1977-2023)

In Australia, comprehensive environmental risk assessments must be performed on transgenic plants (GMOs) prior to their commercial release. A key element is the determination of whether the release of a particular GMO poses any weediness threat to the environment or other agricultural systems, which can occur by means of direct invasion or by introgression of transgenes into wild populations of the same or closely related species. For transgenic pasture plants this question could be of added importance because many of these species have been selected for traits encouraging long-term persistence and competitiveness in complex plant communities (Godfree et al., …


Belowground Meristem Populations As Regulators Of Grassland Dynamics, Harmony J. Dalgleish, D. C. Hartnett Mar 2023

Belowground Meristem Populations As Regulators Of Grassland Dynamics, Harmony J. Dalgleish, D. C. Hartnett

IGC Proceedings (1977-2023)

Studies of plant populations are critical for linking organism to ecosystem-level phenomena and for understanding mechanisms driving responses to global change. In perennial grasslands, the below-ground population of meristems (the bud bank) plays a fundamental role in local plant population recruitment, persistence and dynamics. We explore two aspects of the bud bank in North American grasslands. It has been hypothesized that low variability in arid biomes is explained by meristem limitation, which constrains responses to pulses of high resource availability. Our research tests this hypothesis by comparing bud-bank populations across six sites in the United States that vary 3-fold in …


The Impact Of Vegetation Structure And Spatial Heterogeneity On Invertebrate Biodiversity Within Upland Landscapes, L. Cole, M. L. Pollock, D. Robertson, J. P. Holland, D. I. Mccraken Mar 2023

The Impact Of Vegetation Structure And Spatial Heterogeneity On Invertebrate Biodiversity Within Upland Landscapes, L. Cole, M. L. Pollock, D. Robertson, J. P. Holland, D. I. Mccraken

IGC Proceedings (1977-2023)

Livestock grazing influences vegetation structure and composition at both the patch and wider landscape scale (Milne et al., 1998), and this may have effects on upland invertebrate communities, which in turn influence bird abundance and distribution (Fuller & Gough, 1999; Cole et al., 2002). Of particular importance are open grasslands and wet flushes where invertebrates are abundant and more accessible to birds. However, there have been few studies of invertebrates associated with upland habitats, and most of these have focused on heather moorland, blanket bog, or very fine-scaled structure within grasslands (Dennis et al. 1997; 1998; 2001). This …


Attenuated Skeletal Muscle Metabolism Explains Blunted Reactive Hyperemia After Prolonged Sitting, Cody Anderson, Elizabeth Pekas, Michael Allen, Song-Young Park Mar 2023

Attenuated Skeletal Muscle Metabolism Explains Blunted Reactive Hyperemia After Prolonged Sitting, Cody Anderson, Elizabeth Pekas, Michael Allen, Song-Young Park

UNO Student Research and Creative Activity Fair

Introduction: Although reduced post-occlusive reactive hyperemia (PORH) after prolonged sitting (PS) has been reported as impaired microvascular function, no specific mechanism(s) have been elucidated. One potential mechanism, independent of microvascular function, is that an altered muscle metabolic rate (MMR) may change the magnitude of PORH by modifying the oxygen deficit achieved during cuff-induced arterial occlusions. We speculated that if MMR changes during PS, this may invalidate current inferences about microvascular function during PS. Objective: Therefore, the objective of this study was to examine if peripheral leg MMR changes during PS and to ascertain whether the change in the oxygen deficit …


Problem Of The Week: A Student-Led Initiative To Bring Mathematics To A Broader Audience, Jordan M. Sahs, Brad Horner Mar 2023

Problem Of The Week: A Student-Led Initiative To Bring Mathematics To A Broader Audience, Jordan M. Sahs, Brad Horner

UNO Student Research and Creative Activity Fair

Problem of the Week (POW!) is a weekly undergraduate mathematics competition hosted by two graduate students from the UNO Math Department. It started with the goal to showcase variety, creativity, and intrigue in math to those who normally feel math is dry, rote, and formulaic. Problems shine light on both hidden gems and popular recreational math, both math history and contemporary research, both iconic topics and nontraditional ones, both pure abstraction and real-world application. Now POW! aims to increase availability and visibility in Omaha and beyond. Select problems from Fall 2021 to Spring 2023 are highlighted here: these received noteworthy …


Healthcare Facilities: Maintaining Accessibility While Implementing Security, Ryan Vilter Mar 2023

Healthcare Facilities: Maintaining Accessibility While Implementing Security, Ryan Vilter

UNO Student Research and Creative Activity Fair

In the wake of the Tulsa, Oklahoma hospital shooting in the summer of 2022, it was made clear that more security needed to be implemented in healthcare facilities. As a result, I inquired: What is the happy balance for healthcare facilities to maintain their accessibility to the public while also implementing security measures to prevent terrorist attacks? With that base, I give recommendations in the areas of cybersecurity, physical infrastructure, and physical and mental health, based off the existing literature and data gathered from terrorist attacks against hospitals over several decades.


The Effects Of Demographics And Risk Factors On The Morphological Characteristics Of Human Femoropopliteal Arteries, Sayed Ahmadreza Razian, Majid Jadidi, Alexey Kamenskiy Mar 2023

The Effects Of Demographics And Risk Factors On The Morphological Characteristics Of Human Femoropopliteal Arteries, Sayed Ahmadreza Razian, Majid Jadidi, Alexey Kamenskiy

UNO Student Research and Creative Activity Fair

Background: Disease of the lower extremity arteries (Peripheral Arterial Disease, PAD) is associated with high morbidity and mortality. During disease development, the arteries adapt by changing their diameter, wall thickness, and residual deformations, but the effects of demographics and risk factors on this process are not clear.

Methods: Superficial femoral arteries from 736 subjects (505 male, 231 female, 12 to 99 years old, average age 51±17.8 years) and the associated demographic and risk factor variables were used to construct machine learning (ML) regression models that predicted morphological characteristics (diameter, wall thickness, and longitudinal opening angle resulting from the …


Time Evolution Is A Source Of Bias In The Wolf Algorithm For Largest Lyapunov Exponents, Kolby Brink, Tyler Wiles, Nicholas Stergiou, Aaron Likens Mar 2023

Time Evolution Is A Source Of Bias In The Wolf Algorithm For Largest Lyapunov Exponents, Kolby Brink, Tyler Wiles, Nicholas Stergiou, Aaron Likens

UNO Student Research and Creative Activity Fair

Human movement is inherently variable by nature. One of the most common analytical tools for assessing movement variability is the largest Lyapunov exponent (LyE) which quantifies the rate of trajectory divergence or convergence in an n-dimensional state space. One popular method for assessing LyE is the Wolf algorithm. Many studies have investigated how Wolf’s calculation of the LyE changes due to sampling frequency, filtering, data normalization, and stride normalization. However, a surprisingly understudied parameter needed for LyE computation is evolution time. The purpose of this study is to investigate how the LyE changes as a function of evolution time …