Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

2017

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 10291 - 10320 of 11102

Full-Text Articles in Physical Sciences and Mathematics

On Degree Bound For Syzygies Of Polynomial Invariants, Zhao Gao Jan 2017

On Degree Bound For Syzygies Of Polynomial Invariants, Zhao Gao

Senior Independent Study Theses

Suppose G is a finite linearly reductive group. The degree bound for the syzygy ideal of the invariant ring of G is given in [2]. We develop the theory of commutative algebra and give the proof from [2] that the ideal of relations of the minimal set of generators of invariant ring of a finite linearly reductive group G is generated in degree at most 2|G|.


Grasping The Void: Immersion Tactics Using Gesture Controlled Physics Interaction Systems In Virtual Reality, Avery Rapson Jan 2017

Grasping The Void: Immersion Tactics Using Gesture Controlled Physics Interaction Systems In Virtual Reality, Avery Rapson

Senior Independent Study Theses

This thesis uses the HTC Vive in Unity to compare two different types of object interaction systems in order to determine the effectiveness of physics based interaction systems in a virtual environment. The research problem that motivates this project is the fact that there is no standardized method for defining successful object interaction techniques in VR. There are numerous interaction techniques in VR that fall short of simulating realistic object interaction. This project explores a physics based interaction system and examines how effective it is by comparing it to a non-physics based system. A model house with various interactable objects …


Leveraging The Srtp Protocol For Over-The-Network Memory Acquisition Of A Ge Fanuc Series 90-30, George Denton, Filip Karpisek, Frank Breitinger, Ibrahim Baggili Jan 2017

Leveraging The Srtp Protocol For Over-The-Network Memory Acquisition Of A Ge Fanuc Series 90-30, George Denton, Filip Karpisek, Frank Breitinger, Ibrahim Baggili

Electrical & Computer Engineering and Computer Science Faculty Publications

Programmable Logic Controllers (PLCs) are common components implemented across many industries such as manufacturing, water management, travel, aerospace and hospitals to name a few. Given their broad deployment in critical systems, they became and still are a common target for cyber attacks; the most prominent one being Stuxnet. Often PLCs (especially older ones) are only protected by an outer line of defense (e.g., a firewall) but once an attacker gains access to the system or the network, there might not be any other defense layers. In this scenario, a forensic investigator should not rely on the existing software as it …


Application Of Grating-Based Interferometry To Additive Manufacturing, Lithium-Ion Batteries, And Crystals, Adam Joseph Brooks Jan 2017

Application Of Grating-Based Interferometry To Additive Manufacturing, Lithium-Ion Batteries, And Crystals, Adam Joseph Brooks

LSU Doctoral Dissertations

X-ray and neutron imaging are convenient ways to non-destructively observe novel materials. X-rays provide advantages of low cost and high brilliance while neutrons show bulk and isotopic sensitivity. Imaging provides a way for observing chemical and physical properties of materials without the need for destruction. The way of the imaging future is utilizing imaging with grating-based interferometry. In comparison to traditional radiography and tomography, by using absorption and phase gratings in the beam path, the absorption, phase, and scattering of a sample can be detected. In essence, three image datasets can be obtained in one experiment, saving substantially on costs …


Finding Nondestructive Parameters For Root-To-Shoot Ratios In Douglas-Fir, Grand Fir, And Redwood Saplings In Northwest California For Biomass And Carbon Storage Estimates, Walter A. Kast Jan 2017

Finding Nondestructive Parameters For Root-To-Shoot Ratios In Douglas-Fir, Grand Fir, And Redwood Saplings In Northwest California For Biomass And Carbon Storage Estimates, Walter A. Kast

Cal Poly Humboldt theses and projects

ABSTRACT

FINDING NONDESTRUCTIVE PARAMETERS FOR ROOT-TO-SHOOT RATIOS IN DOUGLAS-FIR, GRAND FIR, AND REDWOOD SAPLINGS IN NORTHWEST CALIFORNIA FOR BIOMASS AND CARBON STORAGE ESTIMATES

Walter A. Kast

There is a need for better understanding of how woody biomass is allocated above and belowground and how this allocation might differ among tree species. In this field of research, investigators face challenges such as the laborious task of removing trees from the soil with destructive sampling, and the cleaning, drying, and weighing of belowground biomass (BGB). Therefore, researchers and practitioners most often rely on existing models to predict BGB from easily-measurable aboveground variables …


Weight Perception And Weight Loss Behaviors: A Comparison Between Adolescents With And Without Autism Spectrum Disorder, Elanor J. Anderson Jan 2017

Weight Perception And Weight Loss Behaviors: A Comparison Between Adolescents With And Without Autism Spectrum Disorder, Elanor J. Anderson

Cal Poly Humboldt theses and projects

OBJECTIVE: The primary purpose of this study is to investigate the accuracy of weight status perception among adolescents with and without Autism Spectrum Disorder. A secondary purpose is to compare weight loss behaviors between children with and without ASD.

METHODS: This study measured weight-perception and weight loss behaviors among Irish-thirteen-year olds with ASD (n=47) and typically developing (TD) children (n=47) (72% male). Participants completed questionnaires assessing perception of weight and weight loss behaviors. . Based on BMI, calculated from height and weight measurements, participants were classified as non-overweight, overweight and obese. Several Chi-square tests were used to examine (1) differences …


Forward Osmosis For Wastewater Treatment And Energy Recovery: A Techno-Economic Analysis, Patrick William Buckwalter Jan 2017

Forward Osmosis For Wastewater Treatment And Energy Recovery: A Techno-Economic Analysis, Patrick William Buckwalter

Cal Poly Humboldt theses and projects

A novel wastewater treatment system was investigated using forward osmosis membranes to treat municipal wastewater. Treatment by forward osmosis was determined to cost $10 million per million gallons per day (MGD) of wastewater capacity over a 20-year lifetime, with an energy consumption of 870 kWh per million gallons. A case study at the Arcata Wastewater Treatment Plant was conducted to investigate a treatment system that combines energy recovery from algae biomass with forward osmosis membrane treatment using local seawater as a draw solution. Total system cost was calculated to be $29.7 million over a 20-year lifetime with a 2.3 MGD …


The Influence Of Canopy Cover And Climate On Early Life-Stage Vital Rates For Northern Red-Legged Frogs (Rana Aurora), And The Implications For Population Growth Rates, Kecly Mcharry Jan 2017

The Influence Of Canopy Cover And Climate On Early Life-Stage Vital Rates For Northern Red-Legged Frogs (Rana Aurora), And The Implications For Population Growth Rates, Kecly Mcharry

Cal Poly Humboldt theses and projects

Many amphibian species are in decline due to habitat loss and changing climates. Understanding how habitat characteristics and climate influence vital rates, and if they act in concert or in opposition can inform management decisions. This study investigated the potential interaction of canopy cover and climate on early stage vital rates of northern red-legged frogs. Demographic data were collected from sample populations in experimental canopy cover treatments across a latitudinal distribution. Rearing cages were used to estimate hatch success, and mark-recapture surveys to estimate tadpole survival. Ambient air temperature was used as an index of climate because it is easily …


Sedimentation And Erosion Patterns Within Anabranching Channels In A Lowland River Restoration Project, Ivan Medel Jan 2017

Sedimentation And Erosion Patterns Within Anabranching Channels In A Lowland River Restoration Project, Ivan Medel

Cal Poly Humboldt theses and projects

Phase 2A of the Salt River Ecosystem Restoration Project (SRERP) was implemented to increase transport efficiency of water and sediment through a low gradient river reach to alleviate flooding on adjacent properties. The SRERP utilizes a unique anabranching channel design that concentrates base flows within a single deep, narrow channel overflowing onto an alternating series of higher elevation active benches at flood stages. This paper investigated the performance of the project’s hydraulic conveyance and general utility of anabranching channels as a restoration alternative by assessing the distribution and magnitude of deposition and erosion response patterns.

Aggradation was not observed within …


Synthesis And Fluorescent Properties Of A New Flavonoid Compound, Ashley L. Ingle Jan 2017

Synthesis And Fluorescent Properties Of A New Flavonoid Compound, Ashley L. Ingle

Williams Honors College, Honors Research Projects

Flavonoids are highly luminescent compounds that are used in diagnosing and treating certain diseases.They are composed of two aromatic rings (ring A and ring B) and a six-membered heterocyclic pyran ring (ring C) that contains a carbonyl and hydroxyl group, which are responsible for unique photophysical characteristics associated with flavonoids. The target flavonoids (compound 1, or 1, and compound 2 or 2) were synthesized, purified and characterized by NMR spectroscopy. The photophysical properties of the flavonoid were investigated in varying solvents by using UV-vis and fluorescence spectroscopy. Such properties include Excited State Intramolecular Proton Transfer (ESIPT), Intramolecular Charge …


Preservation Of Sea Anemone Burrows In Silurian (~432 Million Years Old) Carbonate Rocks Of Southeastern Indiana, Usa, Marissa Tomin Jan 2017

Preservation Of Sea Anemone Burrows In Silurian (~432 Million Years Old) Carbonate Rocks Of Southeastern Indiana, Usa, Marissa Tomin

Williams Honors College, Honors Research Projects

Preservation of trace fossils (ichnofossils) in siliciclastic environments is often quite different from preservation in carbonate environments, representing an important source of variation that must be well understood in order to enhance interpretations of paleoenvironments and paleoecology. This study focuses on Conostichus, a relatively common burrow constructed by solitary sea anemones. These trace fossils are generally well-preserved (i.e., they display detailed external features) in siliciclastic rocks but are typically little more than conical masses in carbonate rocks. However, certain specimens recovered from the middle Silurian Massie Formation at the Napoleon quarry of southeastern Indiana are composed entirely out of …


Statistics-Bierce Library Study, Tyler J. Hushour Jan 2017

Statistics-Bierce Library Study, Tyler J. Hushour

Williams Honors College, Honors Research Projects

This is a report from two surveys that I created and administered to students and faculty at Bierce library who came to the Circulation Desk or the Tech Desk, as well as some of my other findings when periodically looking around the library to see where students like to study or hang-out. There was a written survey given at the Circulation Desk, and a different survey given at the Tech Check-Out Desk. The project is for Melanie Smith-Farrell, the head of Access Services, and is based on a similar study Ian McCullough did in the science library. While this is …


Multiple States Of Nitrile Hydratase From Rhodococcus Equi Tg328-2: Structural And Mechanistic Insights From Electron Paramagnetic Resonance And Density Functional Theory Studies, Natalia Stein, Natalie Gumataotao, Natalia Hajnas, Rui Wu, Karunagala Pathiranage Wasantha Lankathilaka, Uwe Bornscheuer, Dali Liu, Adam T. Fiedler, Richard C. Holz, Brian Bennett Jan 2017

Multiple States Of Nitrile Hydratase From Rhodococcus Equi Tg328-2: Structural And Mechanistic Insights From Electron Paramagnetic Resonance And Density Functional Theory Studies, Natalia Stein, Natalie Gumataotao, Natalia Hajnas, Rui Wu, Karunagala Pathiranage Wasantha Lankathilaka, Uwe Bornscheuer, Dali Liu, Adam T. Fiedler, Richard C. Holz, Brian Bennett

Physics Faculty Research and Publications

Iron-type nitrile hydratases (NHases) contain an Fe(III) ion coordinated in a characteristic “claw setting” by an axial cysteine thiolate, two equatorial peptide nitrogens, the sulfur atoms of equatorial cysteine-sulfenic and cysteine-sulfinic acids, and an axial water/hydroxyl moiety. The cysteine-sulfenic acid is susceptible to oxidation, and the enzyme is traditionally prepared using butyric acid as an oxidative protectant. The as-prepared enzyme exhibits a complex electron paramagnetic resonance (EPR) spectrum due to multiple low-spin (S = 1/2) Fe(III) species. Four distinct signals can be assigned to the resting active state, the active state bound to butyric acid, an …


Active Site Structures Of Cyp11a1 In The Presence Of Its Physiological Substrates And Alterations Upon Binding Of Adrenodoxin, Qianhong Zhu, Piotr J. Mak, Robert C. Tuckey, James R. Kincaid Jan 2017

Active Site Structures Of Cyp11a1 In The Presence Of Its Physiological Substrates And Alterations Upon Binding Of Adrenodoxin, Qianhong Zhu, Piotr J. Mak, Robert C. Tuckey, James R. Kincaid

Chemistry Faculty Research and Publications

The rate-limiting step in the steroid synthesis pathway is catalyzed by CYP11A1 through three sequential reactions. The first two steps involve hydroxylations at positions 22 and 20, generating 20(R),22(R)-dihydroxycholesterol (20R,22R-DiOHCH), with the third stage leading to a C20–C22 bond cleavage, forming pregnenolone. This work provides detailed information about the active site structure of CYP11A1 in the resting state and substrate-bound ferric forms as well as the CO-ligated adducts. In addition, high-quality resonance Raman spectra are reported for the dioxygen complexes, providing new insight into the status of Fe–O–O fragments encountered during the …


Recombination Reactions As A Possible Mechanism Of Mass-Independent Fractionation Of Sulfur Isotopes In The Archean Atmosphere Of Earth, Dmitri Babikov Jan 2017

Recombination Reactions As A Possible Mechanism Of Mass-Independent Fractionation Of Sulfur Isotopes In The Archean Atmosphere Of Earth, Dmitri Babikov

Chemistry Faculty Research and Publications

A hierarchy of isotopically substituted recombination reactions is formulated for production of sulfur allotropes in the anoxic atmosphere of Archean Earth. The corresponding system of kinetics equations is solved analytically to obtain concise expressions for isotopic enrichments, with focus on mass-independent isotope effects due to symmetry, ignoring smaller mass-dependent effects. Proper inclusion of atom-exchange processes is shown to be important. This model predicts significant and equal depletions driven by reaction stoichiometry for all rare isotopes: 33S, 34S, and 36S. Interestingly, the ratio of capital Δ values obtained within this model for 33S and 36S is …


Redox And Spectroscopic Properties Of Iron Porphyrin Nitroxyl In The Presence Of Weak Acids, Md. Hafizur Rahman, Michael D. Ryan Jan 2017

Redox And Spectroscopic Properties Of Iron Porphyrin Nitroxyl In The Presence Of Weak Acids, Md. Hafizur Rahman, Michael D. Ryan

Chemistry Faculty Research and Publications

The spectroelectrochemistry and voltammetry of Fe(OEP) (NO) in the presence of substituted phenols was studied. Cyclic voltammetry showed that two closely spaced waves were observed for the reduction of Fe(OEP) (NO) in the presence of substituted phenols. The first wave was a single electron reduction under voltammetric conditions. The second wave was kinetically controlled, multielectron process. Visible spectroelectrochemistry of Fe(OEP) (NO) in the presence of substituted phenols showed that three species were present during the electrolysis. Additional spectroscopic studies indicated that the two reduction species were Fe(OEP) (HNO) and Fe(OEP)(H2NOH). The Fe(OEP) (HNO) species, which can be generated …


Light-Driven Hydrogen Production From Aqueous Solutions Based On A New Dubois-Type Nickel Catalyst, Y. Zhou, S. Yang, J. Huang Jan 2017

Light-Driven Hydrogen Production From Aqueous Solutions Based On A New Dubois-Type Nickel Catalyst, Y. Zhou, S. Yang, J. Huang

Chemistry Faculty Research and Publications

In this work, we report a new photocatalytic system that links multifunctional semiconductor nanocrystals with emerging water-soluble molecular catalysts made of earth-abundant elements for H2 generation [Ni(P2RN2R′)2(BF4)2]4−, R = Ph, R′ = [PhSO3]− (NiS). This noble metal free hybrid exhibits remarkable catalytic activity with a turnover number of 511 for H2 production and a photon-to-H2 conversion efficiency of 12.5%. The mechanistic insight into such high efficiency in this photocatalytic system was examined using a combination of steady-state emission and time-resolved …


Using Pentosidine And Hydroxyproline To Predict Age And Sex In An Avian Species, Brian S. Dorr, Randal S. Stahl, Katie C. Hanson-Dorr, Carol A. Furcolow Jan 2017

Using Pentosidine And Hydroxyproline To Predict Age And Sex In An Avian Species, Brian S. Dorr, Randal S. Stahl, Katie C. Hanson-Dorr, Carol A. Furcolow

United States Department of Agriculture Wildlife Services: Staff Publications

All living organisms are subject to senescence accompanied by progressive and irreversible physiological changes. The error damage and cross-linking theories suggest that cells and tissues are damaged by an accumulation of cross-linked proteins, slowing down bodily processes and resulting in aging. A major category of these cross-linked proteins are compounds called advanced glycation end products (AGEs). We investigated the relationship between accumulation of the AGE, pentosidine (Ps), and hydroxyproline (HYP) a post-translationally modified amino acid, with age, sex, and breeding status (breeder/ nonbreeder) from skin samples of known age (i.e., banded as fledglings), free-ranging Double-crested Cormorants (Phalacrocorax auritus, …


The Future Of Blackbird Management Research, Page E. Klug Jan 2017

The Future Of Blackbird Management Research, Page E. Klug

United States Department of Agriculture Wildlife Services: Staff Publications

Human society values birds for their intrinsic and aesthetic value as well as the ecosystem services they provide as pollinators, consumers of pests, and distributors of nutrients and seeds (Wenny et al. 2011). At the same time, conflict between birds and humans is an age-old phenomenon that has persisted as society has transformed and the scale of agriculture has expanded (Conover 2002). Managing conflict between birds and agriculture is challenging for many reasons. Foremost, the need to consider both human welfare and conservation of protected bird species is paramount, with nonlethal management methods preferred to lethal measures from societal, economical, …


Size And Shape Control In Metal Nanoparticles And Nanocomposites, Tomendro Subedi Jan 2017

Size And Shape Control In Metal Nanoparticles And Nanocomposites, Tomendro Subedi

Theses and Dissertations (Comprehensive)

This thesis describes major findings on the shape transformation of the precursor silver decahedral nanoparticles (AgDeNPs) with pentagonal symmetry and twin defects into silver pentagonal prism nanoparticles (AgPPNPs) using Br¯ as a shape selective reagent. Silica-encapsulation of the gold-plated AgDeNPs was also carried out forming ordered arrays of silica encapsulated gold-plated AgDeNPs (SiO2@Au@AgDeNPs) of different sizes. At first, synthetic procedures for AgDeNPs (pentagonal bipyramids), silver pentagonal rod nanoparticles (AgPRNPs) and gold-plating of AgDeNPs (Au@AgDeNPs) were optimized. Gold plating enhances the chemical stability of AgDeNPs and preserves the superior plasmonic properties of silver. This thesis deals with the transformation …


Disease Models With Immigration, Reem Almarashi Jan 2017

Disease Models With Immigration, Reem Almarashi

Theses and Dissertations (Comprehensive)

In this thesis we focus first on studying the susceptible, exposed, and infected ($SEI$) disease model without immigration. We determine the basic reproduction number $\mathcal{R}_0$, which can be interpreted as the expected number of new cases that can be produced by a single infection in a completely susceptible population. Further, by using the Jacobian matrix, we determine the local stability of the disease model. Then we have the result that when $\mathcal{R}_0<1$ the DFE point is locally asymptotically stable(L.A.S). In contrast, when $\mathcal{R}_0>1$ we find that the endemic equilibrium is L.A.S. After that, we analyze the $SEI$ model with immigration of infected individuals.

Furthermore, we investigate the direction that the …


Developing A Hydrological Monitoring Program For Ponds In Wapusk National Park, Manitoba, Using Water Isotope Tracers, Stephanie Roy Jan 2017

Developing A Hydrological Monitoring Program For Ponds In Wapusk National Park, Manitoba, Using Water Isotope Tracers, Stephanie Roy

Theses and Dissertations (Comprehensive)

Northern lake-rich landscapes are vulnerable to increases in surface air temperatures and are changing in dynamic ways. Current meteorological records indicate that some of the greatest warming in the past century has occurred in the Hudson Bay Lowlands (HBL). As the HBL is an extensive wetland consisting of hundreds of thousands of shallow lakes and ponds, it is difficult to anticipate the long-term implications that climate change will have on pond water balance. To develop and implement long-term monitoring of hydrological conditions, sampling of pond water isotope composition has occurred during the past six years in Wapusk National Park (WNP), …


Permafrost Thaw Induced Changes To Runoff Generation And Hydrologic Connectivity In Low-Relief, Discontinuous Permafrost Terrains, Ryan Connon Jan 2017

Permafrost Thaw Induced Changes To Runoff Generation And Hydrologic Connectivity In Low-Relief, Discontinuous Permafrost Terrains, Ryan Connon

Theses and Dissertations (Comprehensive)

Recent climate warming in northwestern Canada is occurring at an unprecedented rate in recorded history and has resulted in the widespread thaw of permafrost. Where present, permafrost exerts a significant control on local hydrology, and disappearance of permafrost threatens to change the hydrology of northern basins. In the peatlands that characterise the southern distribution of permafrost in low relief terrain, permafrost takes the form of forested peat plateaus and is interspersed by permafrost-free wetlands (i.e. channel fens and flat bogs). Previous field studies have found that channel fens serve as the drainage network and route water to the basin …


Special Agent Ricin: The Making Of A Scientific Blockbuster, Joy Udoh Jan 2017

Special Agent Ricin: The Making Of A Scientific Blockbuster, Joy Udoh

The Synapse: Intercollegiate science magazine

No abstract provided.


Rigorous Innovation: How Neuroscience Shapes Our View Of Creativity, Emma Hahn Jan 2017

Rigorous Innovation: How Neuroscience Shapes Our View Of Creativity, Emma Hahn

The Synapse: Intercollegiate science magazine

No abstract provided.


Venturing Into The Unknown: The First Human Head Transplant, Christine Craddock Jan 2017

Venturing Into The Unknown: The First Human Head Transplant, Christine Craddock

The Synapse: Intercollegiate science magazine

No abstract provided.


Diy Genetics: The Ethics Of Crispr, Leah Treidler Jan 2017

Diy Genetics: The Ethics Of Crispr, Leah Treidler

The Synapse: Intercollegiate science magazine

No abstract provided.


Gut Check: How Microbiome Research Is Reshaping Our View Of Bacteria In Human Health, Rachel Reardon Jan 2017

Gut Check: How Microbiome Research Is Reshaping Our View Of Bacteria In Human Health, Rachel Reardon

The Synapse: Intercollegiate science magazine

No abstract provided.


Dr. Chie Sakakibara: Collaborative Research With The Iñupiaq People In Utqiagvik, Alaska, Lauren Rhodes Jan 2017

Dr. Chie Sakakibara: Collaborative Research With The Iñupiaq People In Utqiagvik, Alaska, Lauren Rhodes

The Synapse: Intercollegiate science magazine

No abstract provided.


Revisiting A Forgotten Epidemic: West Africa’S Largest Ebola Outbreak Three Years Later, Jayla Johnson Jan 2017

Revisiting A Forgotten Epidemic: West Africa’S Largest Ebola Outbreak Three Years Later, Jayla Johnson

The Synapse: Intercollegiate science magazine

No abstract provided.