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Articles 68221 - 68250 of 294418

Full-Text Articles in Physical Sciences and Mathematics

Chromatic Quasisymmetric Class Functions For Combinatorial Hopf Monoids, Jacob A. White Dec 2021

Chromatic Quasisymmetric Class Functions For Combinatorial Hopf Monoids, Jacob A. White

School of Mathematical & Statistical Sciences Faculty Publications

We study the chromatic quasisymmetric class function of a linearized combinatorial Hopf monoid. Given a linearized combinatorial Hopf monoid H, and an H-structure h on a set N, there are proper colorings of h, generalizing graph colorings and poset partitions. We show that the automorphism group of h acts on the set of proper colorings. The chromatic quasisymmetric class function enumerates the fixed points of this action, weighting each coloring with a monomial. For the Hopf monoid of graphs this invariant generalizes Stanley's chromatic symmetric function and specializes to the orbital chromatic polynomial of Cameron and Kayibi.

We also introduce …


Poor Acclimation To Experimental Field Drought In Subalpine Forest Tree Seedlings, Alex Goke, Patrick H. Martin Dec 2021

Poor Acclimation To Experimental Field Drought In Subalpine Forest Tree Seedlings, Alex Goke, Patrick H. Martin

Biological Sciences: Faculty Scholarship

The ability of tree species to acclimate and tolerate projected increases in drought frequency and intensity has fundamental implications for future forest dynamics with climate change. Inquiries to date on the drought tolerance capacities of tree species, however, have focused almost exclusively on mature trees with scant in situ work on seedlings, despite the central role that regeneration dynamics play in forest responses to changing conditions. We subjected naturally established seedlings of co-dominant subalpine conifer species (Abies lasiocarpa and Picea engelmannii) in the southern Rocky Mountains to 2 years of in situ summer precipitation exclusion, simulating summer drought …


Pentagonal Extensions Of The Rationals Ramified At A Single Prime, Pablo Miguel Rodriguez Dec 2021

Pentagonal Extensions Of The Rationals Ramified At A Single Prime, Pablo Miguel Rodriguez

Theses and Dissertations

In this thesis, we define a certain group of order 160, which we call a hyperpentagonal group, and we prove that every totally real D5-extension of the rationals ramified at only one prime is contained in a hyperpentagonal extension of the rationals. This generalizes a result of Doud and Childers (originally conjectured by Wong) that every totally real S3 extension of the rationals ramified at only one prime is contained in an S4 extension.


Achieving Fairness Through Load-Balancing In Social Cloud Computing Networks, Kaiyi Huang Dec 2021

Achieving Fairness Through Load-Balancing In Social Cloud Computing Networks, Kaiyi Huang

Master's Projects

Cloud-based computing networks have taken over the digital landscape. From small non-profits to large multinational corporations, more and more entities have been offloading computing effort to the cloud in order to take advantage of the increased cost-efficiency and scalability of cloud computing. One of the new types of cloud that have emerged is the P2P cloud, which disengages from a traditional datacenter setup by allowing users to instead share their own computing hardware into a cloud to take advantage of cloud computing’s advantages at an even lower cost. However, this new paradigm comes with a slew of challenges, notably, security …


Nitrogenase Iron Protein Classification Using Cnn Neural Network, Amer Rez Dec 2021

Nitrogenase Iron Protein Classification Using Cnn Neural Network, Amer Rez

Master's Projects

The nitrogenase iron protein (NifH) is extensively used to study nitrogen fixation, the ecologically vital process of reducing atmospheric nitrogen to a bioavailable form. The discovery rate of novel NifH sequences is high, and there is an ongoing need for software tools to mine NifH records from the GenBank repository. Since record annotations are unreliable, because they contain errors, classifiers based on sequence alone are required. The ARBitrator classifier is highly successful but must be initialized by extensive manual effort. A Deep Learning approach could substantially reduce manual intervention. However, attempts to build a character-based Deep Learning NifH classifier were …


The Impact Of Programming Language’S Type On Probabilistic Machine Learning Models, Sherif Elsaid Dec 2021

The Impact Of Programming Language’S Type On Probabilistic Machine Learning Models, Sherif Elsaid

Master's Projects

Software development is an expensive and difficult process. Mistakes can be easily made, and without extensive review process, those mistakes can make it to the production code and may have unintended disastrous consequences.

This is why various automated code review services have arisen in the recent years. From AWS’s CodeGuro and Microsoft’s Code Analysis to more integrated code assistants, like IntelliCode and auto completion tools. All of which are designed to help and assist the developers with their work and help catch overlooked bugs.

Thanks to recent advances in machine learning, these services have grown tremen- dously in sophistication to …


Dynamic Resource Management Of Fog-Cloud Computing For Iot Support, Mariia Surmenok Dec 2021

Dynamic Resource Management Of Fog-Cloud Computing For Iot Support, Mariia Surmenok

Master's Projects

The internet of things (IoT) is an integrated part of contemporary life. It includes wearable devices, such as smart watches and cell phones, as well as sensors for Smart City. Fog computing can improve the efficiency and battery life of IoT devices by offloading tasks to fog cloud. It is important to have fog clusters near the IoT device for faster data offload. The goal of this project is to develop dynamic resource allocation for on-demand fog computing cluster to efficiently deploy tasks from IoT. This report studies the different research papers about the current state of resource management in …


Comparing The Efficiency Of A Marsh-Sill And Oyster Reef Balls In Attenuating Waves, Navid Tahvildari, Alexa Leone Dec 2021

Comparing The Efficiency Of A Marsh-Sill And Oyster Reef Balls In Attenuating Waves, Navid Tahvildari, Alexa Leone

December 17, 2021: Natural and Nature-Based Solutions (Part 2)

No abstract provided.


Carbon Sequestration Benefits Of Coastal Restoration, Brendan Player Dec 2021

Carbon Sequestration Benefits Of Coastal Restoration, Brendan Player

December 17, 2021: Natural and Nature-Based Solutions (Part 2)

No abstract provided.


Living Shorelines Achieve Functional Equivalence To Natural Fringe Marshes Across Multiple Ecological Metrics, Robert E. Isdell, Donna Marie Bilkovic, Amanda G. Guthrie, Molly M. Mitchell, Randolph M. Chambers, Matthias Leu, Carl Hershner Dec 2021

Living Shorelines Achieve Functional Equivalence To Natural Fringe Marshes Across Multiple Ecological Metrics, Robert E. Isdell, Donna Marie Bilkovic, Amanda G. Guthrie, Molly M. Mitchell, Randolph M. Chambers, Matthias Leu, Carl Hershner

December 17, 2021: Natural and Nature-Based Solutions (Part 2)

No abstract provided.


Agenda- Hampton Roads Sea Level Rise/Flooding Adaptation Forum, Ben Mcfarlane, Wie Yusuf Dec 2021

Agenda- Hampton Roads Sea Level Rise/Flooding Adaptation Forum, Ben Mcfarlane, Wie Yusuf

December 17, 2021: Natural and Nature-Based Solutions (Part 2)

Agenda for the Hampton Roads Sea Level Rise/Flooding Adaptation Forum on December 17, 2021 via Virtual Forum.

  • Opening Remarks and Introductions: Ben McFarlane, Hampton Roads Planning District Commission and Dr. Wie Yusuf, Old Dominion University and Virginia Sea Grant
  • Navid Tahvildari, of Old Dominion University: Comparing the Efficiency of a Marsh-Sill and Oyster Reef Balls in Attenuating Waves
  • Brendan Player, of Stantec: Carbon Sequestration Benefits of Coastal Restoration
  • Robert Isdell, of Virginia Institute of Marine Science: Living Shorelines Achieve Functional Equivalence to Natural Fringe Marshes Across Multiple Ecological Metrics
  • Closing Remarks and Reminders


Epa Region 8 Qa Document Review Crosswalk, Nikia Greene Dec 2021

Epa Region 8 Qa Document Review Crosswalk, Nikia Greene

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Draft Residential Metals Abatement Program Quality Assurance Project Plan (Non-Residential Parcels - Indoor Dust), Elsie King, Christopher Berg, Thomas J. Beckman Dec 2021

Draft Residential Metals Abatement Program Quality Assurance Project Plan (Non-Residential Parcels - Indoor Dust), Elsie King, Christopher Berg, Thomas J. Beckman

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Residential Metals Abatement Program Quality Assurance Project Plan (Non-Residential Parcels - Indoor Dust), Environmental Resource Management (Erm), Elsie King, Christopher Berg, Thomas J. Beckman Dec 2021

Residential Metals Abatement Program Quality Assurance Project Plan (Non-Residential Parcels - Indoor Dust), Environmental Resource Management (Erm), Elsie King, Christopher Berg, Thomas J. Beckman

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Distribution, Abundance And Natural Enemies Of The Invasive Tomato Leafminer, Tuta Absoluta (Meyrick) In Kenya, G. Kinyanjui, F. M. Khamis, F. L.O. Ombura, E. U. Kenya, S. Ekesi, S. A. Mohamed Dec 2021

Distribution, Abundance And Natural Enemies Of The Invasive Tomato Leafminer, Tuta Absoluta (Meyrick) In Kenya, G. Kinyanjui, F. M. Khamis, F. L.O. Ombura, E. U. Kenya, S. Ekesi, S. A. Mohamed

All Peer-Reviewed Publications

Tuta absoluta (Meyrick) has become a serious menace to sustainable production of tomato in Kenya. A survey was conducted between April 2015 and June 2016 to determine its distribution, abundance, infestation, and damage levels on tomato, and associated natural enemies. Trap counts of T. absoluta moths were recorded in all surveyed 29 counties, which indicated its nationwide distribution irrespective of altitude. Tuta absoluta was present in both open fields and greenhouses. The highest moth/trap/day was 115.38 ± 15.90. Highest leaf infestation was 92.22% and the highest number of mines and larvae per leaf were 3.71 ± 0.28 and 2.16 ± …


Influence Of Grassland Management And Grazing By Different Farm Animals On Animal Performance And Flora Alterations, W. Jentsch, H.-D. Matthes, A. Admasu, H. Möhring Dec 2021

Influence Of Grassland Management And Grazing By Different Farm Animals On Animal Performance And Flora Alterations, W. Jentsch, H.-D. Matthes, A. Admasu, H. Möhring

IGC Proceedings (1977-2023)

The objectives of this study were to test the possibilities of using different farm animals for landscape care on extensive pasture, taking into account their particular performance, and to analyse alterations of the flora in consequence of grazing by different animals and various pasture management. Salers had the highest (836g/d) and Galloways (584g/d) the lowest live weight gain as compared with the other breeds (771g/d). Lambs had higher live weight when grazing together with cattle and horses (mixed grazing) than under one species grazing. The number of legume increased and that of grass decreased. Following 3 years the grazing animals …


Animal Production From Tropical Pastures Renovated By Subsoiling And Fertilization In The Cerrados Of Brazil, Valéria P. B. Euclides, Manuel C. M. Macedo, M. P. Oliveira Dec 2021

Animal Production From Tropical Pastures Renovated By Subsoiling And Fertilization In The Cerrados Of Brazil, Valéria P. B. Euclides, Manuel C. M. Macedo, M. P. Oliveira

IGC Proceedings (1977-2023)

A grazing trial was conducted, to study the effects of fertilization on the maintenance of the productivity of four tropical grasses. The paddocks were subsoiled, and dived into halves: one (LF1) received 400 kg/ha of a fertilizer formula 0-20-20.and the other (LF2) 800 kg/ha of the same fertilizers, in January 1995. Annually, 50 kg/ha of N was applied. The productivity on LF2 pastures was greater than that on FL1 pastures, averaging 520 and 410 kg of liveweight gain/ha/year. A double strategy should be followed to sustain animal production in the savanna: maintain soil P over a critical value of 3.0 …


Performance Of Nellore Cattle Under Two Grazing Management Systems, L. De A. Corrêa, Maurício M. De Alencar, Rogério T. Barbosa, P. F. Barbosa, Geraldo M. Da Cruz, I. U. Packer, C. A. Cordeiro Dec 2021

Performance Of Nellore Cattle Under Two Grazing Management Systems, L. De A. Corrêa, Maurício M. De Alencar, Rogério T. Barbosa, P. F. Barbosa, Geraldo M. Da Cruz, I. U. Packer, C. A. Cordeiro

IGC Proceedings (1977-2023)

The objective of this study was to evaluate the effects of grazing intensification on birth weight (BW), weaning weight (WW, standartized to 205 days), average daily gain from birth to weaning (ADG), and gestation length (GL) of calves, cow weight at calving (CWC) and at weaning (CWW), cow condition score at calving (CCC) and at weaning (CCW), and BW/CWC (BWR), WW/CWC (WWRC) and WW/CWW (WWRW) ratios. One hundred and sixty eight Nellore calves born in 1998 and 1999, out of dams maintained in two grazing management systems were evaluated: an extensive 1.0 animal unity (AU). ha-1 system on unfertilized …


Orchardgrass Pastures For Early-Weaned Beef Calves, J. C. Waller, H. A. Fribourg, C. Dixon, A. E. Fisher, B. V. Conger Dec 2021

Orchardgrass Pastures For Early-Weaned Beef Calves, J. C. Waller, H. A. Fribourg, C. Dixon, A. E. Fisher, B. V. Conger

IGC Proceedings (1977-2023)

Orchardgrass (Dactylis glomerata) grown alone or with ladino white (Trifolium repens) and red (T. pratense) clovers, provides a high quality March to June pasture. However, many beef producers have their cows calving in January-March, thus producing offspring that are too young to utilize spring forage well. As an alternative, some producers have their cows bred so that calves are born in autumn (September-November). By spring, these calves are old enough to consume pasture forage. The few earlier studies on early weaning of fall-born calves consist of drylot feeding of high quality hay or concentrates. …


Sustainable Irrigation Based On Co-Regulation Of Soil Water Supply And Atmospheric Evaporative Demand, Jingwen Zhang, Kaiyu Guan, Bin Peng, Ming Pan, Wang Zhou, Chongya Jiang, Hyungsuk Kimm, Trenton E. Franz, Robert F. Grant, Yi Yang, Daran R. Rudnick, Derek M. Heeren, Andrew E. Suyker, William L. Bauerle, Grace L. Miner Dec 2021

Sustainable Irrigation Based On Co-Regulation Of Soil Water Supply And Atmospheric Evaporative Demand, Jingwen Zhang, Kaiyu Guan, Bin Peng, Ming Pan, Wang Zhou, Chongya Jiang, Hyungsuk Kimm, Trenton E. Franz, Robert F. Grant, Yi Yang, Daran R. Rudnick, Derek M. Heeren, Andrew E. Suyker, William L. Bauerle, Grace L. Miner

School of Natural Resources: Faculty Publications

Irrigation is an important adaptation to reduce crop yield loss due to water stress from both soil water deficit (low soil moisture) and atmospheric aridity (high vapor pressure deficit, VPD). Traditionally, irrigation has primarily focused on soil water deficit. Observational evidence demonstrates that stomatal conductance is co-regulated by soil moisture and VPD from water supply and demand aspects. Here we use a validated hydraulically-driven ecosystem model to reproduce the co-regulation pattern. Specifically, we propose a plant-centric irrigation scheme considering water supply-demand dynamics (SDD), and compare it with soil-moisture-based irrigation scheme (management allowable depletion, MAD) for continuous maize cropping systems in …


Expres. Iii. Revealing The Stellar Activity Radial Velocity Signature Of Ε Eridani With Photometry And Interferometry, Rachael M. Roettenbacher, Samuel H. C. Cabot, Debra A. Fischer, John D. Monnier, Gregory W. Henry, Robert O. Harmon, Heidi Korhonen, John M. Brewer, Joe Llama, Ryan R. Petersburg, Lily L. Zhao, Stefan Kraus, Jean-Baptiste Le Bouquin, Narsireddy Anugu, Claire L. Davies, Tyler Gardner, Cyprien Lanthermann, Gail Schaefer, Benjamin Setterholm, Catherine A. Clark, Svetlana G. Jorstad, Kyler Kuehn, Stephen Levine Dec 2021

Expres. Iii. Revealing The Stellar Activity Radial Velocity Signature Of Ε Eridani With Photometry And Interferometry, Rachael M. Roettenbacher, Samuel H. C. Cabot, Debra A. Fischer, John D. Monnier, Gregory W. Henry, Robert O. Harmon, Heidi Korhonen, John M. Brewer, Joe Llama, Ryan R. Petersburg, Lily L. Zhao, Stefan Kraus, Jean-Baptiste Le Bouquin, Narsireddy Anugu, Claire L. Davies, Tyler Gardner, Cyprien Lanthermann, Gail Schaefer, Benjamin Setterholm, Catherine A. Clark, Svetlana G. Jorstad, Kyler Kuehn, Stephen Levine

Information Systems and Engineering Management Research Publications

The distortions of absorption line profiles caused by photospheric brightness variations on the surfaces of cool, main-sequence stars can mimic or overwhelm radial velocity (RV) shifts due to the presence of exoplanets. The latest generation of precision RV spectrographs aims to detect velocity amplitudes ≲ 10 cm s−1, but requires mitigation of stellar signals. Statistical techniques are being developed to differentiate between Keplerian and activity-related velocity perturbations. Two important challenges, however, are the interpretability of the stellar activity component as RV models become more sophisticated, and ensuring the lowest-amplitude Keplerian signatures are not inadvertently accounted for in flexible …


Magnitude And Uncertainty Of Nitrous Oxide Emissions From North America Based On Bottom-Up And Top-Down Approaches: Informing Future Research And National Inventories, R. Xu, Hanqin Tian, N. Pan, R. L. Thompson, J. G. Canadell, E. A. Davidson, C. Nevison, W. Winiwarter, H. Shi, S. Pan, J. Chang, P. Ciais, Shree Dangal, A. Ito, R. B. Jackson, F. Joos, R. Lauerwald, S. Lienert, T. Maavara, D. B. Millet, P. A. Raymond, P. Regnier, F. N. Tubiello, N. Vuichard, K. C. Wells, C. Wilson, J. Yang, Y. Yao, S. Zaehle, F. Zhou Dec 2021

Magnitude And Uncertainty Of Nitrous Oxide Emissions From North America Based On Bottom-Up And Top-Down Approaches: Informing Future Research And National Inventories, R. Xu, Hanqin Tian, N. Pan, R. L. Thompson, J. G. Canadell, E. A. Davidson, C. Nevison, W. Winiwarter, H. Shi, S. Pan, J. Chang, P. Ciais, Shree Dangal, A. Ito, R. B. Jackson, F. Joos, R. Lauerwald, S. Lienert, T. Maavara, D. B. Millet, P. A. Raymond, P. Regnier, F. N. Tubiello, N. Vuichard, K. C. Wells, C. Wilson, J. Yang, Y. Yao, S. Zaehle, F. Zhou

School of Natural Resources: Faculty Publications

We synthesized N2O emissions over North America using 17 bottom-up (BU) estimates from 1980– 2016 and five top-down (TD) estimates from 1998 to 2016. The BU-based total emission shows a slight increase owing to U.S. agriculture, while no consistent trend is shown in TD estimates. During 2007–2016, North American N2O emissions are estimated at 1.7 (1.0–3.0) Tg N yr−1 (BU) and 1.3 (0.9–1.5) Tg N yr−1 (TD). Anthropogenic emissions were twice as large as natural fluxes from soil and water. Direct agricultural and industrial activities accounted for 68% of total anthropogenic emissions, 71% of …


Selective Oxidation Of Alkenes In Air Catalyzed By Mn3o4 Nanoparticles, Brojo Kishor Shachib Dhali Dec 2021

Selective Oxidation Of Alkenes In Air Catalyzed By Mn3o4 Nanoparticles, Brojo Kishor Shachib Dhali

Dissertations and Theses

Catalytic oxidation is a process where compounds are oxidized using catalysts. Solid catalysts exhibit several advantages over homogeneous systems, such as catalyst recovery and excellent stability. Various supported transition-metal oxides (for example: CuO, ZnO, CeO2, Fe2O3 and WO3), metal nanoparticles (for example: Pd and Ru) and polyoxometalate clusters (for example: [W10O32]4-, [Mn2ZnW(ZnW9O34)2]10- and [XW12O40]n- (X = P, Si)) have been applied to selective oxidation of organic compounds, but high associated product conversion still remains a challenge. Recently, a number of materials containing Mn3O4 have been used successfully in different catalytic applications, such as degradation of phenols, reduction of nitrobenzenes, and …


A Distance-Based Clustering Framework For Categorical Time Series: A Case Study In Episodes Of Care Healthcare Delivery System, Lauren Staples Dec 2021

A Distance-Based Clustering Framework For Categorical Time Series: A Case Study In Episodes Of Care Healthcare Delivery System, Lauren Staples

Doctor of Data Science and Analytics Dissertations

Understanding how compensation structures influence overall healthcare costs is a central issue in health economics. Episodes of Care (EoC) is a compensation structure that bundles payments for healthcare interventions that belong to a well-defined health event. Since the variation of clinical pathways can drive the cost of healthcare, this research uses sequences of medical billing codes in Perinatal Episodes of Care claims data to study the extent of that variation by equating it to the number of reproducible clusters found. This research proposes a methodological framework to detect reproducible clusters in an unsupervised problem where the true number of clusters …


Characterization Of Landfill Leachate For Enhanced Metal Recovery, Hanna Fulford, Amisha Shah, Inez Hua, Nadezhda Zyaykina, Lori Hoagland, Alejandro Rodriguez Sanchez, Umut Bicim Dec 2021

Characterization Of Landfill Leachate For Enhanced Metal Recovery, Hanna Fulford, Amisha Shah, Inez Hua, Nadezhda Zyaykina, Lori Hoagland, Alejandro Rodriguez Sanchez, Umut Bicim

Discovery Undergraduate Interdisciplinary Research Internship

Landfills contain a trove of valuable materials, such as critical, precious, and rare earth metals, that are integral to the United State’s economy and national security. The leachate that filters through landfills picks up these materials, which allows for the possibility of recovery. For this research, samples will be analyzed from landfills throughout the Midwestern United States to provide a baseline on water quality constituents, elements present, and microbial activity. Preliminary data for this study was acquired by analyzing samples of landfill leachate from a landfill in northern Indiana. pH readings indicate that the leachate is slightly basic. It also …


Using Facies Analysis And Reservoir Characterization Of The Albian-Cenomanian Nanushuk Formation To Assist In Better Understanding Interactions Between Shoreface, Deltaic, And Fluvial Systems On The North Slope, Alaska, Andrea Smoot Dec 2021

Using Facies Analysis And Reservoir Characterization Of The Albian-Cenomanian Nanushuk Formation To Assist In Better Understanding Interactions Between Shoreface, Deltaic, And Fluvial Systems On The North Slope, Alaska, Andrea Smoot

Theses and Dissertations

The Albian-Cenomanian Nanushuk Formation located on the North Slope of Alaska is the result of fluvial, deltaic, and shoreface processes and has been the focus of recent petroleum exploration activity in the Colville Basin. The Nanushuk and underlying Torok formations together contain an estimated 8.7 billion barrels of oil and 25 trillion cubic feet of natural gas reserves within the resource-rich North Slope. The Nanushuk Formation is composed of sediment sourced from the Chukotka Peninsula to the west and deposited axially within the Colville Basin. High sedimentation rates led to rapid progradation of shoreface and deltaic systems, which effectively filled …


Intracavity Phase Interferometry Based Fiber Sensors, Luke Jameson Horstman Dec 2021

Intracavity Phase Interferometry Based Fiber Sensors, Luke Jameson Horstman

Optical Science and Engineering ETDs

Intracavity Phase Interferometry (IPI) is a detection technique that exploits the inherent sensitivity of a laser's frequency to the parameters of its cavity. Intracavity interferometry is orders of magnitude more sensitive than its extracavity alternatives. This dissertation improves on previous free-space proof-of-concept designs. By implementing the technique in fiber optics, using optical parametric oscillation, and investigating non-Hermitian quantum mechanics and dispersion tailoring enhancement techniques, IPI has become more applicable and sensitive. Ring and linear IPI configurations were realized in this work, both operating as bidirectional fiber optical parametric oscillators. The benefit of using externally pumped synchronous optical parametric oscillation is …


An Open Source Direct Messaging And Enhanced Recommendation System For Yioop, Aniruddha Dinesh Mallya Dec 2021

An Open Source Direct Messaging And Enhanced Recommendation System For Yioop, Aniruddha Dinesh Mallya

Master's Projects

Recommendation systems and direct messaging systems are two popular components of web portals. A recommendation system is an information filtering system that seeks to predict the "rating" or "preference" a user would give to an item and a direct messaging system allows private communication between users of any platform. Yioop, is an open source, PHP search engine and web portal that can be configured to allow users to create discussion groups, blogs, wikis etc.

In this project, we expanded on Yioop’s group system so that every user now has a personal group. Personal groups were then used to add user …


Ecological Exposure And Effects Of Microplastics In Crabs Along The Pacific Coast, Dorothy A. Horn Dec 2021

Ecological Exposure And Effects Of Microplastics In Crabs Along The Pacific Coast, Dorothy A. Horn

Dissertations and Theses

Microplastics have been documented across the global oceans as an ubiquitous pollutant. Found in the water column, sediment, shorelines, estuaries, freshwater streams and rivers along with terrestrial soils, flora and fauna. The continuous input of plastic waste into the marine environment doesn't seem to be slowing as the amount of plastic created each year increases globally.

This study investigated (1) the effects of microplastic ingestion in the indicator species, the Pacific mole crab (Emerita analoga), testing the predator avoidance behavior, reproductive output and parasitism effects when an adult female gravid crab had ingested microplastics (2) adult mortality, hatching …


Paleoindian Response To Climate Change In The Northern Jornada Del Muerto, Christopher Wayne Merriman Dec 2021

Paleoindian Response To Climate Change In The Northern Jornada Del Muerto, Christopher Wayne Merriman

Anthropology ETDs

Human-environment interaction is a long-standing and productive line of inquiry that includes the study of cultural responses to climate change. However, demonstrating a causal relationship between climate change and the consequent culture change is rarely straightforward for numerous reasons. In this dissertation I develop an optimality model to predict how Paleoindians should have responded to changes in precipitation across the Late Pleistocene-Early Holocene. The water supply model (WSM) ranks water supplies much like the diet breadth model ranks food resources. To adjust the WSM for climate change, paleoclimate records from playas in the northern Jornada del Muerto were used in …