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Full-Text Articles in Physical Sciences and Mathematics

Investigation Into The Control Of Melittin Secondary Structure And Antimicrobial Activity, Zachary B. Molinets Jul 2014

Investigation Into The Control Of Melittin Secondary Structure And Antimicrobial Activity, Zachary B. Molinets

Open Access Theses

Antimicrobial resistance has been an exponentially growing problem since the discovery of antibiotics. Antibiotics have been misused for many years and this misuse has grown into a real problem for the medical community. While there are countless safeguards to prevent infection by a resistant strain of bacteria, there are still many plagued by it and must be treated with sometimes dangerous antibiotics. Melittin, along with many other peptides, contain potent antimicrobial properties, but are also toxic toward enthrocytes. The control of the secondary structure of peptides provides the key to adjusting their activity.


Synthesis And Dna-Binding Studies With Two Stericallyfriendly Porphyrin Frameworks, Srijana Ghimire Jul 2014

Synthesis And Dna-Binding Studies With Two Stericallyfriendly Porphyrin Frameworks, Srijana Ghimire

Open Access Dissertations

Peripheral substituents on cationic porphyrins play a significant role during binding with DNA hosts. Possible applications of these systems in photodynamic therapy as well as in anti-bacterial and anti-cancer therapies motivate the binding studies. For characterizing DNA binding motifs different methods are useful including absorption, emission, and circular dichroism spectroscopies, as well as viscometry and X-ray crystallography. With the classic H2 T4 porphyrin, or 5,10,15,20-tetra(N-methylpyridinium-4-yl)porphyrin, the mode of binding varies with the base composition of the DNA host. The porphyrin binds adenine-thymine rich sequences externally whereas intercalation occurs in guanine-cytosine rich sequences. The McMillin group has made some …


Field To Flight: A Techno-Economic Analysis Of Stover To Aviation Biofuels Supply Chain, Amanda C. Bittner Jul 2014

Field To Flight: A Techno-Economic Analysis Of Stover To Aviation Biofuels Supply Chain, Amanda C. Bittner

Open Access Theses

Greenhouse gas emissions have been a growing concern. The transportation sector contributes to one-third of GHG emissions in the United States from fossil fuel burning. The Renewable Fuel Standard set a requirement for 16 billion gallons (ethanol equivalent) of cellulosic biofuels to be used in the market. Aviation biofuels can help to meet both of these problems as well as improve U.S. energy security.

Investment in the biofuel industry carries a lot of risk. The biofuel industry is run by the private sector, but can be incentivized by government. Cellulosic biofuels carry even more risk than first generation biofuels, because …


Changes In Tundra Plant And Soil Organic Geochemical Composition In Response To Long-Term Increased Winter Precipitation In N. Alaska, Olivia Miller Jul 2014

Changes In Tundra Plant And Soil Organic Geochemical Composition In Response To Long-Term Increased Winter Precipitation In N. Alaska, Olivia Miller

Open Access Theses

Tundra ecosystem soils store half of the global soil organic carbon (SOC) pool and have the potential to release large amounts of greenhouse gases, primarily CH4 and CO2. As climates warm and permafrost thaws, the emissions of these gases as organic matter decomposition rates increase may become increasingly important to the chemistry of the atmosphere. Increases in precipitation that accompany warming, may shift tundra vegetative composition from moss/graminoid- to shrub-dominated systems. These vegetation shifts may result in important feedback effects as altered plant and litter chemistry may affect SOC storage in soils. Questions investigated include: 1) How …


Draft Genome Sequence Of Acetobacter Aceti Strain 1023, A Vinegar Factory Isolate, John Hung, Christopher Mill, Sandra Clifton, Vincent Magrini, Ketaki Bhide, Julie Francois, Aaron Ransome, Lucinda Fulton, Jyothi Thimmapuram, Richard Wilson, T. Joseph Kappock Jun 2014

Draft Genome Sequence Of Acetobacter Aceti Strain 1023, A Vinegar Factory Isolate, John Hung, Christopher Mill, Sandra Clifton, Vincent Magrini, Ketaki Bhide, Julie Francois, Aaron Ransome, Lucinda Fulton, Jyothi Thimmapuram, Richard Wilson, T. Joseph Kappock

Cyber Center Publications

The genome sequence of Acetobacter aceti 1023, an acetic acid bacterium adapted to traditional vinegar fermentation, comprises 3.0 Mb (chromosome plus plasmids). A. aceti 1023 is closely related to the cocoa fermenter Acetobacter pasteurianus 386B but possesses many additional insertion sequence elements.


Metal Stopping Reagents Facilitate Discontinuous Activity Assays Of The De Novo Purine Biosynthesis Enzyme Pure, Kelly L. Sullivan, Loredana C. Huma, Elwood Mullins, Michael E. Johnson, T. Joseph Kappock May 2014

Metal Stopping Reagents Facilitate Discontinuous Activity Assays Of The De Novo Purine Biosynthesis Enzyme Pure, Kelly L. Sullivan, Loredana C. Huma, Elwood Mullins, Michael E. Johnson, T. Joseph Kappock

Department of Biochemistry Faculty Publications

The conversion of 5-aminoimidazole ribonucleotide (AIR) to 4-carboxy-AIR (CAIR) represents an unusual divergence in purine biosynthesis: microbes and nonmetazoan eukaryotes use class I PurEs while animals use class II PurEs. Class I PurEs are therefore a potential antimicrobial target; however, no enzyme activity assay is suitable for high throughput screening (HTS). Here we report a simple chemical quench that fixes the PurE substrate/product ratio for 24 h, as assessed by the Bratton-Marshall assay (BMA) for diazotizable amines. The ZnSO4 stopping reagent is proposed to chelate CAIR, enabling delayed analysis of this acid-labile product by BMA or other HTS methods


A Practical Approach For Provenance Transmission In Wireless Sensor Networks, S.M. Iftekharul Alam, Sonia Fahmy May 2014

A Practical Approach For Provenance Transmission In Wireless Sensor Networks, S.M. Iftekharul Alam, Sonia Fahmy

Cyber Center Publications

Assessing the trustworthiness of sensor data and transmitters of this data is critical for quality assurance. Trust evaluation frameworks utilize data provenance along with the sensed data values to compute the trustworthiness of each data item. However, in a sizeable multi-hop sensor network, provenance information requires a large and variable number of bits in each packet, resulting in high energy dissipation due to the extended period of radio communication. In this paper, we design energy-efficient provenance encoding and construction schemes, which we refer to as Probabilistic Provenance Flow (PPF). Our work demonstrates the feasibility of adapting the Probabilistic Packet Marking …


Deforestation Of Cloud Forest In The Central Highlands Of Guatemala: Soil Erosion And Sustainability Implications For Q'Eqchi' Maya Communities, Ian Christopher Pope Apr 2014

Deforestation Of Cloud Forest In The Central Highlands Of Guatemala: Soil Erosion And Sustainability Implications For Q'Eqchi' Maya Communities, Ian Christopher Pope

Open Access Theses

Understanding the nexus between deforestation, food production, land degradation, and culture contributes knowledge that is useful for development practitioners working to enhance conservation and food security. Documenting deforestation and soil erosion in the Sierra Yalijux and Sierra Sacranix in the Central Highlands of Guatemala adds new knowledge about the rates and dynamics of deforestation and land degradation in areas with unique and sensitive cloud forest ecosystems. It also suggests possible areas of emphasis for efforts targeted at combining cloud forest conservation with sustainability for indigenous Q'eqchi' communities. In addition, this work contributes to a small but growing body of literature …


Determinants Of Energy Efficiency Across Countries, Guolin Yao Apr 2014

Determinants Of Energy Efficiency Across Countries, Guolin Yao

Open Access Theses

With economic development, environmental concerns become more important. Economies cannot be developed without energy consumption, which is the major source of greenhouse gas emissions. Higher energy efficiency is one means of reducing emissions, but what determines energy efficiency?

In this research we attempt to find answers to this question by using cross-sectional country data; that is, we examine a wide range of possible determinants of energy efficiency at the country level in an attempt to find the most important causal factors. All countries are divided into three income groups: high-income countries, middle-income countries, and low-income countries. Energy intensity is used …


Study Of The Sustainbility Issues Of Food Production Using Vertical Farm Methods In An Urban Environment Within The State Of Indiana, Victor Mendez Perez Apr 2014

Study Of The Sustainbility Issues Of Food Production Using Vertical Farm Methods In An Urban Environment Within The State Of Indiana, Victor Mendez Perez

Open Access Theses

There are several problems around the globe related to water scarcity, energy shortages, deforestation and loss of fertile land, and food security. Climate change is making environmental and social issues arise. Issues such as, changes in the agricultural landscape, increasing population (9 billion is the expected population for 2040), rising food borne illnesses, scarcity of drinking water, and more crop failure due to plant pathogens and insect pests, among other factors make this study specially significant. Vertical farming could be a potencial solution to some of these problems.

Due to these problems the present thesis analyzed vertical farming as a …


Pharmaceuticals And Personal Care Products: Emerging Contaminants In Aquatic Ecosystems, Jenny E. Zenobio Apr 2014

Pharmaceuticals And Personal Care Products: Emerging Contaminants In Aquatic Ecosystems, Jenny E. Zenobio

Open Access Theses

In recent years, the presence of pharmaceuticals and personal care products (PPCPs) in aquatic systems has led to research on their fate and effects. PPCPs have been found in mixture in wastewater effluents, surface, ground, and drinking water at low concentrations from areas of intense urbanization. Although adverse effects to human health from the current environmental concentrations are unlikely, the impacts to ecological receptors are not clear. We performed field and laboratory studies to quantify and evaluate effects of PPCPs on fish. First, a field study was conducted at the Baca National Wildlife Refuge, Colorado (2010-2012) because a portion of …


Security Of Graph Data: Hashing Schemes And Definitions, Muhammad U. Arshad, Ashish Kundu, Elisa Bertino, Krishna Madhavan, Arif Ghafoor Mar 2014

Security Of Graph Data: Hashing Schemes And Definitions, Muhammad U. Arshad, Ashish Kundu, Elisa Bertino, Krishna Madhavan, Arif Ghafoor

Cyber Center Publications

Use of graph-structured data models is on the rise - in graph databases, in representing biological and healthcare data as well as geographical data. In order to secure graph-structured data, and develop cryptographically secure schemes for graph databases, it is essential to formally define and develop suitable collision resistant one-way hashing schemes and show them they are efficient. The widely used Merkle hash technique is not suitable as it is, because graphs may be directed acyclic ones or cyclic ones. In this paper, we are addressing this problem. Our contributions are: (1) define the practical and formal security model of …


Randomized And Efficient Authentication In Mobile Environments, Wei Jiang, Dan Lin, Feng Li, Elisa Bertino Feb 2014

Randomized And Efficient Authentication In Mobile Environments, Wei Jiang, Dan Lin, Feng Li, Elisa Bertino

Cyber Center Publications

In a mobile environment, a number of users act as a network nodes and communicate with one another to acquire location based information and services. This emerging paradigm has opened up new business opportunities and enables numerous applications such as road safety enhancement, service recommendations and mobile entertainment. A fundamental issue that impacts the success of these applications is the security and privacy concerns raised regarding the mobile users. In that, a malicious user or service provider can track the locations of a user traveled so that other malicious act can be carried out more effectively against the user. Therefore, …


Identidroid: Android Can Finally Wear Its Anonymous Suit, Bilal Shebaro, Oyindamola Oluwatimi, Daniele Midi, Elisa Bertino Jan 2014

Identidroid: Android Can Finally Wear Its Anonymous Suit, Bilal Shebaro, Oyindamola Oluwatimi, Daniele Midi, Elisa Bertino

Cyber Center Publications

Because privacy today is a major concern for mobile applications, network anonymizers are widely available on smartphones, such as Android. However despite the use of such anonymizers, in many cases applications are still able to identify the user and the device by different means than the IP address. The reason is that very often applications require device services and information that go beyond the capabilities of anonymous networks in protecting users’ identity and privacy. In this paper, we propose two solutions that address this problem. The first solution is based on an approach that shadows user and application data, device …


Dj-1 And Atp13a2: Two Proteins Involved In Parkinson’S Disease, Josephat M Asiago Jan 2014

Dj-1 And Atp13a2: Two Proteins Involved In Parkinson’S Disease, Josephat M Asiago

Open Access Dissertations

Parkinson's disease (PD) is the second most common neurodegenerative disorder after Alzheimer's disease, affecting approximately 0.3% of the total U.S. population, and its prevalence increases with age. Two neuropathological hallmarks of PD are the loss of dopaminergic neurons in the substantia nigra pars compacta, a region in the midbrain involved in initiating and sustaining movement, and the presence of cytosolic inclusions called Lewy bodies (LBs) in various brain regions. LBs are enriched with fibrillar forms of the presynaptic protein &agr;-synuclein (aSyn). Two autosomal recessive genes implicated in familial PD are PARK9, encoding the P-type ATPase ATP13A2, a lysosomal ATPase; and …