Life Sciences Commons^™

Whole-Stand Carbon Gains And Nitrogen Distribution In Herbaceous Stands, M.J A. Werger, T Hirose

IGC Proceedings (1993-2023)

We studied canopy structure and leaf nitrogen distribution in open and dense stands of tall dicot and monocot herbs and compared the results with simulated canopy performance under uniform and optimised leaf nitrogen distributions. Dense stands showed leaf nitrogen distributions that greatly differed from those of uniform distribution but did not completely match optimum distribution. In dense stands this led to strongly enhanced potential whole canopy carbon gains, while in open stands the leaf nitrogen distribution was not very important in this respect. Dense stands of monocots kept more leaf nitrogen in the lower parts of their canopies than is …

Environmental Physiology Of Medical Cannabis, F. Mitchell Westmoreland

All Graduate Theses and Dissertations, Fall 2023 to Present

Cannabis (Cannabis sativa L.) is increasingly being cultivated for industrial and medical uses. Medical cannabis is grown for cannabinoids and terpenes, compounds that continue to show promising therapeutic potential. Cannabidiol (CBD) and delta-9- tetrahydrocannabinol (Δ9-THC) are the two most common cannabinoids, but more than 150 have been identified in cannabis. The 2018 Farm Bill federally legalized cannabis containing less than 0.3% THC and high-THC medical cannabis is legal in 38 states. There is a need to understand environmental effects on yield and quality to ensure safety and quality for medical use.

The cultivation of medical cannabis is centered around …

The Influence Of Light On The Succession Of Calcareous Grassland Using A Gis As An Instrument For Analysis, G Spatz, Th Fricke

IGC Proceedings (1993-2023)

The change of light transmission along a gradient from shrub center to open grassland and its correlation to vegetation composition has been studied in two shrub surroundings on abandoned calcareous grassland. Light measurements were made at soil surface locations in high density and later interpolated to area maps. Low-growing plants were mapped in plots within the shrub area and their shapes subsequently digitized. Using SPANS GIS an overlay of maps representing light transmission, distance to shrub center and apearance of low-growing plants was made by calculating averages in a specified grid to create data sets for a statistical evaluation. The …

Analyzing Phototaxis And Related Visual Behaviors Among Diverse Species Of Drosophila, Madeline M. Hill

Honors Theses

Phototaxis and related visual behaviors can vary between species, and thus members of the genus Drosophila make an excellent study system to examine the evolution of vision. While some existing research points to these phototactic behaviors arising due to mating requirements or due to their species-specific ecology or environmental factors, there exists a lack of understanding as to why striking behavioral differences can exist between closely related species, or between members belonging to the same genus. The present research seeks to uncover the specifics regarding these discrepancies in visual evolution and aims to provide a foundation of knowledge about visual …

Bloom Or Bust: An Interdisciplinary Exploration Of Flowering Plants And How Climate Change Impacts Them, Carolyn Schmode

WWU Honors College Senior Projects

Plants are vital to both natural ecosystems and human society. As climate change progresses, more frequent extreme weather events threaten the biodiversity of the Pacific Northwest. Plant responses to flooding, drought, temperature, and light involve signal transduction pathways that alter flowering times. As flowering times shift, plant/pollinator interactions decrease, limiting the plants' ability to survive and reproduce. My capstone is a literature review synthesizing how plants respond to changes in their environment related to climate change. I also explore plants as art, highlighting the importance of an interdisciplinary approach to the way we interact with plants.

Computational Modeling And Minimization Of Unintended Neuronal Excitation In A Lifu Stimulation, Boqiang Fan, Wayne Goodman, Raymond Y Cho, Sameer A Sheth, Richard R Bouchard, Behnaam Aazhang

Student and Faculty Publications

The neuromodulation effect of low-intensity focused ultrasound (LIFU) is highly target-specific. Unintended off-target neuronal excitation can be elicited when the beam focusing accuracy and resolution are limited, whereas the resulted side effect has not been evaluated quantitatively. There is also a lack of methods addressing the minimization of such side effects. Therefore, this work introduces a computational model of unintended neuronal excitation during LIFU neuromodulation, which evaluates the off-target activation area (OTAA) by integrating an ultrasound field model with the neuronal spiking model. In addition, a phased array beam focusing scheme called constrained optimal resolution beamforming (CORB) is proposed to …

The Effect Of Water Flow Rates On The Survival And Growth Rates Of Three Caribbean Bouldering Coral Species Juveniles In An Indoor Versus Outdoor Environment, Ian Michael Johnson

All HCAS Student Capstones, Theses, and Dissertations

Coral reefs are vital ecosystems for the world’s oceans and humanity; however, they are threatened by climate change, disease, and local anthropogenic stressors, and need assistance to recover. Traditional reef restoration efforts (fragmentation and outplanting are helping but are limited in effectiveness by not increasing genetic diversity. Ex situ sexual propagation for corals provides new, genetically different coral recruits. However, this process is laborious, expensive and time consuming, especially at the scale required to effectively contribute to the widespread recovery. To lower costs, two key parameters that require optimization to hasten the growth of coral recruits are water flow and …

Light Intensity Is Positively Correlated With The Synthesis Of Condensed Tannins In Lotus Corniculatus, Sergio Arcioni, T. Bovone, F. Damiani, F. Paolocci

IGC Proceedings (1993-2023)

The importance of Condensed Tannins (CT) in forage legumes has been well documented in several studies. The role of plant genetics in this field is the acquisition of competences in order to be able to modulate CT synthesis in leaves of these species. The role of light has been investigated in this work on the increase of condensed tannin levels in leaves of two contrasting genotypes of birdsfoot trefoil (Lotus corniculatus).

Sequential Absorption Of Two Photons Creates A Bistable Form Of Rubyacr Responsible For Its Strong Desensitization, Oleg A Sineshchekov, Elena G Govorunova, Hai Li, Yumei Wang, John L Spudich

Faculty and Staff Publications

Channelrhodopsins with red-shifted absorption, rare in nature, are highly desired for optogenetics because light of longer wavelengths more deeply penetrates biological tissue. RubyACRs (Anion ChannelRhodopsins), a group of four closely related anion-conducting channelrhodopsins from thraustochytrid protists, are the most red-shifted channelrhodopsins known with absorption maxima up to 610 nm. Their photocurrents are large, as is typical of blue- and green-absorbing ACRs, but they rapidly decrease during continuous illumination (desensitization) and extremely slowly recover in the dark. Here, we show that long-lasting desensitization of RubyACRs results from photochemistry not observed in any previously studied channelrhodopsins. Absorption of a second photon by …

The Effects Of Light Intensity And Cell Structure On The Cultivation Of Arthrospira Platensis, Taylor Barnhart

Honors Theses

As scientists explore further into space, more cost-effective resources are needed for long-term space travel. An interesting solution is Arthrospira platensis, a filamentous cyanobacteria high in proteins and nutrients, and known for its helical structure. In unfavorable conditions, coiled spirulina cells become straight. Spirulina converts carbon dioxide gas into pure oxygen and the different cell structures stimulate different responses in oxygen production and cultivation. In these experiments, 2.3 L containers of pure coiled spirulina and mixed (coiled and straight) spirulina were placed into 3 incubators with different light intensities: 51μmol/m2/s, 25μmol/m2/s, 12μmol/m2/s. Each experiment length was 72 hours and the …

Nitrite Cycling In The Primary Nitrite Maxima Of The Eastern Tropical North Pacific, Nicole M. Travis, Colette L. Kelly, Margaret R. Mulholland, Karen L. Casciotti

OES Faculty Publications

The primary nitrite maximum (PNM) is a ubiquitous feature of the upper ocean, where nitrite accumulates in a sharp peak at the base of the euphotic zone. This feature is situated where many chemical and hydrographic properties have strong gradients and the activities of several microbial processes overlap. Near the PNM, four major microbial processes are active in nitrite cycling: ammonia oxidation, nitrite oxidation, nitrate reduction and nitrite uptake. The first two processes are mediated by the nitrifying archaeal/bacterial community, while the second two processes are primarily conducted by phytoplankton. The overlapping spatial habitats and substrate requirements for these microbes …

Levels Of Autotrophy And Heterotrophy In Mesophotic Corals Near The End Photic Zone, Amy Carmignani, Veronica Z. Radice, Kathryn M. Mcmahon, Alex I. Holman, Karen Miller, Kliti Grice, Zoe Richards

Biological Sciences Faculty Publications

Mesophotic corals live at ~30-150 m depth and can sustain metabolic processes under light-limited conditions by enhancing autotrophy through specialized photoadaptations or increasing heterotrophic nutrient acquisition. These acclimatory processes are often species-specific, however mesophotic ecosystems are largely unexplored and acclimation limits for most species are unknown. This study examined mesophotic coral ecosystems using a remotely operated vehicle (Ashmore Reef, Western Australia at 40–75m depth) to investigate the trophic ecology of five species of scleractinian coral (from genera Leptoseris, Pachyseris, and Craterastrea) using stable isotope analyses (δ¹³C and δ¹⁵N) of host and symbiont tissues …

In Light Of Breathing: Environmental Light Is An Important Modulator Of Breathing With Clinical Implications, Aaron A. Jones, Deanna M. Arble

Biological Sciences Faculty Research and Publications

In vertebrate animals, the automatic, rhythmic pattern of breathing is a highly regulated process that can be modulated by various behavioral and physiological factors such as metabolism, sleep–wake state, activity level, and endocrine signaling. Environmental light influences many of these modulating factors both indirectly by organizing daily and seasonal rhythms of behavior and directly through acute changes in neural signaling. While several observations from rodent and human studies suggest that environmental light affects breathing, few have systematically evaluated the underlying mechanisms and clinical relevance of environmental light on the regulation of respiratory behavior. Here, we provide new evidence and discuss …

Bbt Acoustic Alternative Top Bracing Cadd Data Set-Norev-2022jun28, Bill Hemphill

STEM Guitar Project’s BBT Acoustic Kit

This electronic document file set consists of an overview presentation (PDF-formatted) file and companion video (MP4) and CADD files (DWG & DXF) for laser cutting the ETSU-developed alternate top bracing designs and marking templates for the STEM Guitar Project’s BBT (OM-sized) standard acoustic guitar kit. The three (3) alternative BBT top bracing designs in this release are
(a) a one-piece base for the standard kit's (Martin-style) bracing,
(b) 277 Ladder-style bracing, and
(c) an X-braced fan-style bracing similar to traditional European or so-called 'classical' acoustic guitars.

The CADD data set for each of the three (3) top bracing designs includes …

Vegetative Phenologies Of Lianas And Trees In Two Neotropical Forests With Contrasting Rainfall Regimes, Jose A. Medina-Vega, S. Joseph Wright, Frans Bongers, Stefan A. Schnitzer, Frank J. Sterck

Biological Sciences Faculty Research and Publications

• Among tropical forests, lianas are predicted to have a growth advantage over trees during seasonal drought, with substantial implications for tree and forest dynamics. We tested the hypotheses that lianas maintain higher water status than trees during seasonal drought and that lianas maximize leaf cover to match high, dry-season light conditions, while trees are more limited by moisture availability during the dry season.
• We monitored the seasonal dynamics of predawn and midday leaf water potentials and leaf phenology for branches of 16 liana and 16 tree species in the canopies of two lowland tropical forests with contrasting rainfall regimes in …

Investigation Into The Responses Of Physcomitrella Patens To Herbivory And The Influence Of Light On The Production Of Defense Compounds, Matthew Morris

Undergraduate Honors Thesis Collection

Plant defense mechanisms are well studied in many agriculturally relevant crops such as corn and tomatoes. Though less studied, the more ancestral nonvascular plants may be able to provide insights into the origin and working of modern plant defense systems. In this study, the bryophyte Physcomitrella patens was researched and the role of the jasmonic acid pathway in response to herbivory was investigated. Additionally, the impact of light intensity on the efficacy of this pathway was to be determined. After exposing the moss to various chemical elicitors and mechanical wounding, the activity of proteins produced in the JA pathway was …

Influence Of Abiotic Drivers On 1-Year Seedling Survival Of Six Mangrove Species In Southeast Asia, Taylor M. Sloey, Kiah Eng Lim, Jared Moore, Jie Min Heng, Jia Min Heng, Michiel Van Breugel

Biological Sciences Faculty Publications

Establishment and survival of plant species in systems with dominant environmental drivers (i.e. factors that exert disproportionate control over species establishment and survival) is often thought to be dominated by one master variable. In forested wetlands such as mangroves, hydrology is typically considered the dominant limiting driver. At the same time, light is a major driver of plant community dynamics, with some of the best understood plant life-history tradeoffs related to fast growth under high-light conditions versus survival under low-light conditions. Yet light is given relatively limited consideration in mangrove research compared to other drivers. Understanding the relative importance of …

Germination Characteristics Of Haloxylon Bunge Seeds, L. R. Tong, J. G. Han

IGC Proceedings (1993-2023)

No abstract provided.

Effects Of Anthropogenic Light And Noise On Anuran Breeding Behavior, Ashley Kobisk

Electronic Theses and Dissertations

The natural environment can be negatively impacted by a variety of human activities, including the production of artificial light at night and anthropogenic noise. Recent studies suggest that pollution from anthropogenic light and noise alters animal behavior. Despite being highly nocturnal and vocal animals, little attention has been given to anurans and the effects artificial light at night and anthropogenic noise have on their behavior. This study investigated the effects of artificial light at night and anthropogenic noise on anuran breeding systems in eastern Texas. Specifically, this study investigated whether (1) artificial light and anthropogenic noise altered calling behavior in …

Works Of The Famous Central Asian Scientist Abu Ali Ibn Sina In The Field Of Physics, Malokhat Akhadovna Vakhobova, Munira Ibragimovna Akhrorova

Scientific reports of Bukhara State University

Introduction. This article examines the scientific and practical work of the sultan of the science of medicine Abu Ali ibn Sina in the field of physics. In the rare masterpieces created by Ibn Sina, his ideas about the structure of mater, the laws of dynamics, natural phenomena, the eye and vision, the historical data in the correspondence of Ibn Sina and Beruni were studied to explain the essence of the content of physics. Research methods. The actual task of physical science is the movement of bodies under the influence of the same force placed on bodies of different masses, their …

Conserving Critical Seagrass Habitat For Dugong. Seagrass Network Monitoring Data Summary, Kathryn M. Mcmahon, Paul Lavery, Nicole Said

Research Datasets

This is the summary dataset of the seagrass monitoring data containing benthic habitat, seagrass meadow characteristics, seed density and environmental variables from three locations in the Pilbara over 3-4 time periods in 2018-2019.

Light Dependent Morpho-Physiological Changes And Yield Response Of Hybrid Napier Cultivars Under Rainfed System, Savitha Antony, C. George Thomas

IGC Proceedings (1993-2023)

For small dairy farmers in the tropics, open land for fodder cultivation is often limited because of the predominance of tree crops and paddies. Probably because of this limitation, to offset fodder supply for the livestock, growing fodder crops under tree crops such as coconut is a widely prevalent practice in the tropics. However, successful establishment and growth of most fodder crops especially high yielding types such as hybrid napier under shade depends on the amount of light available and the consequent morpho-physiological responses of the crops.

Optimizing Animal Welfare In Commercial Laying Hens Through Novel Management Practices And Farm Manager Evaluation, John R. Brunnquell

Theses and Dissertations--Animal and Food Sciences

The commercial production of pasture and free-range eggs in the United States is expanding rapidly. According to the United States Department of Agriculture Agricultural Management Assistance, in May of 2019 there were 2.6M pasture hens and 4.5M free-range hens representing 1.9% of the nation’s laying flock. There is little industry and/or academic experience with this style of production in the United States. Programs such as the European Layer Training Initiative (ELTI), which emerged in 2019, have tried to fill this void but participation from the US was low. The principal sources for guidance of commercial free-range egg production in the …

The Effects Of Light Level And Temperature On Freshwater Microbial Biomass, Production, Enzyme Activity, And Community Composition, Joel Bonney

Master's Theses and Doctoral Dissertations

Algae can stimulate the production of heterotrophic microbes in periphyton communities, but the synergistic effects of light and temperature on this phenomenon are not well understood and have implications on carbon cycling and energy flow. We employed recirculating mesocosms held at different temperatures and light levels and filled with Typha litter and attached microbes to assess these effects. Heterotrophic microbial production was greater in the presence of light, as were some periphytic enzyme activities. Few response variables increased in a near-linear fashion with ascending temperature, suggesting different temperature optima. The strength of heterotrophic microbial production responses to algal photosynthesis did …

Assessing Threats And Mitigation For Scarlet Ammannia (Ammannia Robusta) In Southwestern Ontario, Kayla Salive

Theses and Dissertations (Comprehensive)

Scarlet Ammannia (Ammannia robusta) is an annual emergent wetland plant of the Lythraceae family. Throughout most of its distribution, the species population is stable under present conditions. However, this is not the case in Canada, where A. robusta is considered endangered with only a few small populations documented in British Columbia and Ontario. In response, a recovery strategy was created for A. robusta outlining the lack of information on the species biology and ecology, with a primary objective to assess the populations in Ontario and gain information on what may be contributing to the species rarity. To assess …

Optimizing Lighting Regimes For Rearing Orbicella Faveolata And Acropora Cervicornis Recruits, Paul D. Kreh

HCNSO Student Theses and Dissertations

Coral reef decline worldwide has led to the need for coral reef restoration. The use of sexual reproduction in restoration efforts is required to increase genetic diversity; however, the procedures for rearing newly-settled coral recruits ex situ still need to be optimized. Recruits initially require low light irradiance, but it is unclear when higher irradiances are required to enhance growth and survival. Here we determined the optimal light regime for Orbicella faveolata and Acropora cervicornis recruits. Newly settled recruits were reared under treatments with varied rates of increasing irradiance (after reaching 5 weeks of age), and their survival, growth, and …

Contrasting Development Of Canopy Structure And Primary Production In Planted And Naturally Regenerated Red Pine Forests, Laura J. Hickey, Jeff Atkins, Robert T. Fahey, Mark R. Kreider, Shea B. Wales, Christopher M. Gough

Ecology Center Publications

Globally, planted forests are rapidly replacing naturally regenerated stands but the implications for canopy structure, carbon (C) storage, and the linkages between the two are unclear. We investigated the successional dynamics, interlinkages and mechanistic relationships between wood net primary production (NPP_w) and canopy structure in planted and naturally regenerated red pine (Pinus resinosa Sol. ex Aiton) stands spanning ≥ 45 years of development. We focused our canopy structural analysis on leaf area index (LAI) and a spatially integrative, terrestrial LiDAR-based complexity measure, canopy rugosity, which is positively correlated with NPP_w in several naturally regenerated forests, but …

On The Composistion Of Cymodocea Nodosa Root Exudate Under Artificial Blue, Green And Natural Light Conditions, Armand Martin, Ben Manriquez, Christian Pompa, Aaron Saper, Kyle A. Grice, Jason Bystriansky

DePaul Discoveries

Seagrasses are identified as a sentinel species: a good indicator of overall marine ecosystem health and function. At the rhizome, they are known to interact with marine bacteria by exchanging energy in the form of glucose and free amino acids secreted through root exudate in exchange for microbe-fixated nitrogen that can be utilized for plant growth. To analyze potential outcomes of possible future changes in light availability, an experiment was designed to collect and analyze the root exudate of Cymodocea nodosa under three light conditions (standard fluorescent light, blue LED, and green LED light). After 72 hours of treatment, the …

The Effects Of Ambient Temperature And Lighting Intensity On Wheel-Running Behavior In A Diurnal Rodent, The Nile Grass Rat (Arvicanthis Niloticus), Garrett M. Fogo, Alyssa M. Goodwin, Ohanes S. Khacherian, Brandi J. Ledbetter, Andrew J. Gall

Faculty Publications

Environmental conditions, such as the light-dark cycle and temperature, affect the display of circadian rhythmicity and locomotor activity patterns in mammals. Here, we tested the hypothesis that manipulating these environmental conditions would affect wheel-running activity patterns in a diurnal rodent, the Nile grass rat (Arvicanthis niloticus). Grass rats are diurnal in the field, however, a subset switch from a day-active pattern to a night-active pattern of activity after the introduction of a running wheel. The mechanism of this chronotype switch remains largely unknown. In the present study, grass rats were presented with running wheels in 12:12 light-dark conditions. First, subjects …

The Potential Roles Of Melanopsin Signaling In Mediating The Effects Of Environmental Light On Voluntary Ethanol Intake In Mice, Rachel Brooks

Honors College

Intrinsically photosensitive retinal ganglion cells (ipRGCs) comprise a small subset of photoreceptors found in the eye containing the newly discovered photopigment, melanopsin. ipRGCs project directly to the hypothalamic suprachiasmatic nucleus (SCN), the central “pacemaker” underlying the generation and entrainment of circadian rhythms. Photic stimuli detected by ipRGCs are transmitted to the SCN via the retinohypothalamic tract (RHT), mediating the entrainment of the SCN pacemaker. In addition to circadian entrainment, these pathways may also contribute to seasonal changes seen in both animals and humans, such as seasonal breeding cycles in animals and seasonal affective disorder in humans. Our lab has recently …