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Purdue University

2013

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Articles 1 - 30 of 126

Full-Text Articles in Life Sciences

Functional Analysis Of The Acetic Acid Resistance (Aar) Gene Cluster In Acetobacter Aceti Strain 1023, Elwood Mullins, T Joseph Kappock Dec 2013

Functional Analysis Of The Acetic Acid Resistance (Aar) Gene Cluster In Acetobacter Aceti Strain 1023, Elwood Mullins, T Joseph Kappock

Department of Biochemistry Faculty Publications

Vinegar production requires acetic acid bacteria that produce, tolerate, and conserve high levels of acetic acid. When ethanol is depleted, aerobic acetate overoxidation to carbon dioxide ensues. The resulting diauxic growth pattern has two logarithmic growth phases, the first associated with ethanol oxidation and the second associated with acetate overoxidation. The vinegar factory isolate Acetobacter aceti strain 1023 has a long intermediate stationary phase that persists at elevated acetic acid levels. Strain 1023 conserves acetic acid despite possessing a complete set of citric acid cycle (CAC) enzymes, including succinyl-CoA:acetate CoA-transferase (SCACT), the product of the acetic acid resistance (aar …


Detection Of Foodborne Pathogens By Micro-Filtration Using A Continuous Cell Concentrator Device, Klaire E. Jeffries, Eduardo Ximenes, Michael R. Ladisch Oct 2013

Detection Of Foodborne Pathogens By Micro-Filtration Using A Continuous Cell Concentrator Device, Klaire E. Jeffries, Eduardo Ximenes, Michael R. Ladisch

The Summer Undergraduate Research Fellowship (SURF) Symposium

Protecting consumers from foodborne illness is an important health concern facing the food industry today. An important deficiency exposed by foodborne illness is the inability to track contaminated food back to the source in a timely manner. Although there are established methods that detect bacterial pathogen contamination, they are limited in distinguishing viable bacteria reliably and quickly. Currently, food pathogen testing requires lengthy culture steps, which many times are delayed even longer due to the lack of in-house testing labs. Typically, two to three days elapses between when the food is sampled and the test results are available. This study …


Study Of Coronavirus Protease Using Cfp-Yfp Fluorescent Assay, Caitlin E. Specht, Andrew Mesecar Ph.D., Katrina Molland Ph.D. Oct 2013

Study Of Coronavirus Protease Using Cfp-Yfp Fluorescent Assay, Caitlin E. Specht, Andrew Mesecar Ph.D., Katrina Molland Ph.D.

The Summer Undergraduate Research Fellowship (SURF) Symposium

Middle Eastern Respiratory Syndrome (MERS) is an emerging viral disease originating in the Arabian Peninsula with a current mortality rate of nearly fifty percent throughout Europe and Asia according to the World Health Organization. Characterization of this disease is being done to understand the basis of viral replication. One target for viral inhibition are replication proteases. Replication proteases are enzymes that cleave proteins specific to cell growth and reproduction that form the viral replicase complex making them an ideal target for viral replication inhibition. First, replication proteases were characterized using a fluorescence resonance energy transfer (FRET) construct by measuring the …


Cellular Uptake Mechanism Of Paclitaxel Nanocrystals, Iris K. Archer, Zhaohui Wang, Tonglei Li Oct 2013

Cellular Uptake Mechanism Of Paclitaxel Nanocrystals, Iris K. Archer, Zhaohui Wang, Tonglei Li

The Summer Undergraduate Research Fellowship (SURF) Symposium

Therapeutic options for metastasized human cancer in current practice remain limited and, sadly, there is no cure for metastatic cancer. The typical approach, chemotherapy, has both low efficacy due to poor drug solubility, and cytotoxic side effects to healthy tissue when delivered indiscriminately. To address both of these issues, we are pursuing the use of nanocrystal formulations of current chemotherapeutic agents as delivery platforms. Herein, we have studied cellular uptake mechanisms in cancer cells of nanocrystals of a chemotherapeutic agent, paclitaxel. Our goal in this study is to determine whether the nanocrystals can be taken up via endocytosis, especially when …


Identification Of Set1 Target Genes, William Beyer, Scott D. Briggs Oct 2013

Identification Of Set1 Target Genes, William Beyer, Scott D. Briggs

The Summer Undergraduate Research Fellowship (SURF) Symposium

The Set1 complex, a histone methyltransferase complex found in S. cerevisiae (budding yeast), is the only histone methyltransferase responsible for catalyzing methylation of histone H3 at Lysine 4. It possesses homologues in other species, humans included. While yeast only have the Set1 complex, the human homologues of the yeast Set1 complex include mixed-lineage leukemia family (MLL1-4), Set1 A, Set1 B, among others. MLL1-4 has been shown to play a role in transcription, cell type specification, and the development of leukemia. One application of characterizing the role of a protein is that the information gained can provide insight into the function …


Forward Genetic Screen Of Trichomes For Discovery Of Cytoskeleton-Based Mutants, Adam M. Fessenden, Samuel Belteton, Daniel B. Szymanski Oct 2013

Forward Genetic Screen Of Trichomes For Discovery Of Cytoskeleton-Based Mutants, Adam M. Fessenden, Samuel Belteton, Daniel B. Szymanski

The Summer Undergraduate Research Fellowship (SURF) Symposium

Understanding plant cell development and what genes influence cell growth can lead to breakthroughs in beneficial areas such as bioremediation, agricultural production, and biofuels. However, information on many of the genes that control plant cell growth is either unknown or severely limited. Further research to fully comprehend the genetic pathways within the cells will enable the genetic engineering of plants to further benefit society. One approach is the combined use of a forward genetic screen, sophisticated growth analysis, and gene identification. Using Arabidopsis thaliana trichomes, leaf hairs, as a model system, the mutagenized population of thousands of plants was screened …


Synthesis And Characterization Of Nucleic Acid-Functionalized Nanomaterials, Brianna S. Carroll, Jong Hyun Choi Oct 2013

Synthesis And Characterization Of Nucleic Acid-Functionalized Nanomaterials, Brianna S. Carroll, Jong Hyun Choi

The Summer Undergraduate Research Fellowship (SURF) Symposium

Motor proteins such as kinesin move along microtubules in order to transport cellular cargos throughout the cell by obtaining energy from RNA hydrolysis which allows the cell to complete the tasks needed to stay alive. In this work, we developed synthetic molecular motors using DNA enzymes (DNAzyme) and fluorescent nanomaterials which mimic the functions and structures of motor proteins. A DNAzyme-capped CdS nanoparticle and a RNA-functionalized single-walled carbon nanotube (SWCNT) were used as a walker and a track in the motor platform, respectively. As a walking mechanism, the DNAzyme cleaved the RNA substrates in the presence of metal cations. The …


Bicistronic Design For Precise And Reliable Gene Expression, Nidhi N. Menon, Jenna Rickus Oct 2013

Bicistronic Design For Precise And Reliable Gene Expression, Nidhi N. Menon, Jenna Rickus

The Summer Undergraduate Research Fellowship (SURF) Symposium

Despite having progressed extensively in the field of synthetic biology in terms of DNA synthesis, analysis and transplanting, we still cannot reliably, quantitatively measure expression of new genetic constructs. We engineered a biobrick compatible expression cassette to control transcription and translation initiation which can be reused in new genetic contexts. Previous research has shown that the Bicistronic design have much lesser variations in expression with varying genes of interest as compared to the regular monocistronic design.(Mutalik, Endy, Guimaraes, Cambray, Lam, Juul, Tran & Paull, 2013) The Bicistronic design(BCD) consists of two Shine-Dalgarno sequences in its translation element which when combined …


Involvement Of Post-Transcriptional Histone Modifications In Chromosome Missegregation, Jessica N. Gabbard, Ann Kirchmaier Oct 2013

Involvement Of Post-Transcriptional Histone Modifications In Chromosome Missegregation, Jessica N. Gabbard, Ann Kirchmaier

The Summer Undergraduate Research Fellowship (SURF) Symposium

Proper chromosome segregation during mitosis ensures the equal inheritance of parental DNA by two daughter cells. Errors in chromosome segregation result in aneuploidy, the inheritance of abnormal chromosome numbers. Aneuploidy is a characteristic of tumors cells; therefore, understanding the factors that cause chromosome missegregation will provide insight into carcinogenesis. Certain post-transcriptional histone modifications in centromeric and pericentromeric regions are associated with maintaining kinetochore integrity and ensuring proper chromosome segregation. However, whether loss or improper distribution of modifications directly or indirectly causes chromosome missegregation is yet to be determined. To compare the DNA content of mutated yeast strains relative to WT, …


Determination Of Master Compliance Curve For Extruded Semolina Pasta, Laura E. Emery, Martin Okos Oct 2013

Determination Of Master Compliance Curve For Extruded Semolina Pasta, Laura E. Emery, Martin Okos

The Summer Undergraduate Research Fellowship (SURF) Symposium

The dependence of the rate of relaxation of semolina pasta on moisture content and temperature and how it affects shrinkage during drying has not yet been determined. The purpose of this research was to develop an equation that relates moisture content and temperature in order to obtain a master curve for creep of the product. When found, this equation could help to optimize the drying process and increase the quality of the final pasta product. Semolina flour mixed with water and propionic acid to create a 35% wet basis product was extruded on a C.W. Brabender 2523 to obtain a …


Artificial Yeast Polarization Controlled By Chemical Gradient, James K. Nolan, Bernard Tao Oct 2013

Artificial Yeast Polarization Controlled By Chemical Gradient, James K. Nolan, Bernard Tao

The Summer Undergraduate Research Fellowship (SURF) Symposium

Engineering synthetic multicellular systems will lead to new synthetic biology technological platforms, inform developmental biology through recapitulation of natural systems and possibly unveil novel morphologies with practical applications not before reached throughout natural history (Maharbiz, 2012). Creating an exogenous molecular circuit that will polarize unicellular cells into “apical” and “basal” domains relative to a substrate plane would fulfill a missing component towards fully multicellular synthetic cellular communities (Maharbiz, 2012). To this end, a PIP3 polarization network previously designed by Chau and associates (Chau, Walter, Gerardin, Tang, Lim 2012) was coupled to the specific activation by niacin of a recombinant …


Saccharomyces Cerevisiae Cdc7 Homology In Drosophila Melanogaster, Marcus R. Hosler, Robert E. Stephenson, Vikki M. Weake Oct 2013

Saccharomyces Cerevisiae Cdc7 Homology In Drosophila Melanogaster, Marcus R. Hosler, Robert E. Stephenson, Vikki M. Weake

The Summer Undergraduate Research Fellowship (SURF) Symposium

Saccharomyces cerevisiae Dbf4(Dumbbell former 4) and Cdc7(Cell Division Cycle 7) form a complex that phosphorylates Mcm2 (Minichromosome maintenance 2) to initiate DNA replication. Cdc7 is a target for cancer research because there is a Cdc7 ortholog in humans that is necessary for DNA replication and cell survival. Our goal is to characterise a putative Cdc7 homolog in Drosophila melanogaster (dCdc7). We have previously shown that expression of the known Drosophila Dbf4 ortholog, Chiffon, and dCdc7 can rescue yeast cells deficient in active Cdc7. Our hypothesis is that the dCdc7 is activated by Chiffon to phosphorylate MCM2. To test this hypothesis, …


In Vivo Method For Labeling And Tracking Cells In The Mammalian Limb Bud, James T. Mccarthy, Andrew Schilb, Sarah Calve Oct 2013

In Vivo Method For Labeling And Tracking Cells In The Mammalian Limb Bud, James T. Mccarthy, Andrew Schilb, Sarah Calve

The Summer Undergraduate Research Fellowship (SURF) Symposium

The extracellular matrix (ECM) is composed of many different proteins excreted by cells and is believed to play a very important role in development as well as regeneration and wound healing. In this research, a method to determine the ECM’s effect on the migration of muscle progenitor cells into the mammalian limb bud was investigated. It has traditionally been difficult to obtain in vivo images of the limb bud, due to the difficulty of maintaining embryos in culture and limitations of imaging techniques. In this study, we have worked on optimizing the culture conditions to allow growth of mouse embryos …


Non-Mass Transfer Limited Crystal Growth, Ryan J. Smyth, Caitlin Schram, Stephen P. Beaudoin Oct 2013

Non-Mass Transfer Limited Crystal Growth, Ryan J. Smyth, Caitlin Schram, Stephen P. Beaudoin

The Summer Undergraduate Research Fellowship (SURF) Symposium

There are many different active pharmaceutical ingredients (APIs) that have been discovered in research labs all around the world that can be used to treat and cure patients with a variety of different ailments. The challenge with these APIs in treatments is that they are not soluble in water, thus they low absorption into the blood stream (bio-availability). The key to making these APIs more bio-available is to understand how they grow as crystals and drop out of the aqueous solutions. One of the ways these APIs were made more bio-available is to render them amorphous and suspend them in …


Compositional Analysis Of Carbohydrates Of A Family Of Legumes, Arvind Raghothama, Bruce Hamaker Oct 2013

Compositional Analysis Of Carbohydrates Of A Family Of Legumes, Arvind Raghothama, Bruce Hamaker

The Summer Undergraduate Research Fellowship (SURF) Symposium

Legumes, most commonly identified as beans or lentils, provide a good source of both protein and carbohydrates. Many legumes contain the polysaccharide arabinogalactans, classified as dietary fiber and have unique functional properties in foods. However, these, and other plant polysaccharides have not been well characterized. A preliminary collaborative study between Florida State University and the Whistler Center at Purdue indicated that isolated legume arabinogalactans appear to have high texturizing capability through formation of viscoelastic structures. Their soluble property may also present unique fiber nutritional trait. These properties of arabinogalactans and their variability among different legumes are yet to be analyzed. …


Development Of A Metabolomic Method To Define The Phenylalanome In Arabidopsis Thaliana, Cole G. Wunderlich, Clint Chapple, Xu Li Oct 2013

Development Of A Metabolomic Method To Define The Phenylalanome In Arabidopsis Thaliana, Cole G. Wunderlich, Clint Chapple, Xu Li

The Summer Undergraduate Research Fellowship (SURF) Symposium

In the study of metabolomics, one of the greatest challenges can be accurately identifying compounds detected in biological extracts, especially when standards are not readily available. Current metabolomic methods are also limited in that they provide little to no information about a compound’s metabolic origin. In this study, we sought to address these issues by developing a novel metabolomic method that employs stable isotope feeding, LC-MS, Xcms, and an analytical software algorithm to study the ‘phenylalanome’ of Arabidopsis thaliana. Using this approach we were able to develop a method that, based on current results, is capable of detecting over …


Fabrication Of Multilayered Structure For Coherent Random Lasing, John Rauchenstein, Young L. Kim Oct 2013

Fabrication Of Multilayered Structure For Coherent Random Lasing, John Rauchenstein, Young L. Kim

The Summer Undergraduate Research Fellowship (SURF) Symposium

High powered lasers have many applications, including medical treatment and surgery. However, these lasers are extremely expensive and are therefore not widely available. The aim of this study was to demonstrate a method to create such a laser with significantly decreased overall cost and increased efficiency. In order to do this, we explored a phenomenon called random lasing which is a light amplification process. To start with, a low-cost pumping laser is directed at normal incidence toward a multi-layered sample with two alternating layers. At first pearl, a naturally found material that has many organic nano-scale layers (similar to the …


Hair-Cell-Specific Genes In The Embryonic Chicken Inner Ear By Overexpression, Eric S. Traub, Donna Fekete Oct 2013

Hair-Cell-Specific Genes In The Embryonic Chicken Inner Ear By Overexpression, Eric S. Traub, Donna Fekete

The Summer Undergraduate Research Fellowship (SURF) Symposium

The inner ear houses organs used for hearing and balance that use hair cells to accomplish their tasks. Inner ear development remains to be fully understood, and advancing knowledge in development could lead to therapies and treatments for hearing problems. A gene called Atoh1 is necessary for hair cell formation and has been shown to increase hair cell number when overexpressed. Importantly, microRNAs from the 183 family (miRs-183, -182, and -96) are also expressed in developing hair cells. MicroRNAs are small RNA molecules that bind to messenger RNAs and prevent translation. MicroRNAs have been associated with cellular functions such as …


Optimization Of Oil Extraction Of Soy Flour Using Mini Extrusion Technology, Alisha Chess, Martin Okos Oct 2013

Optimization Of Oil Extraction Of Soy Flour Using Mini Extrusion Technology, Alisha Chess, Martin Okos

The Summer Undergraduate Research Fellowship (SURF) Symposium

Mini extrusion technology is a relatively new technology that offers fast timing and processing of food products. This technology paired with the advantageous properties and growing demand for soybeans can lead to a larger span of uses for the extruder that have not yet been explored, including NASA space missions and incorporation of soybeans into developing countries. During past research on parameters of operation, it was discovered that a significant amount of oil was being separated from the soy meal at the die of the mini extruder. Maximum removal of this oil allows use of the soy meal and soy …


Analysis Of Neuronal And Microglial Responses To Implanted Silicon Devices Through Immunohistochemistry And Clarity, Michael A. Leathers, Kevin J. Otto Oct 2013

Analysis Of Neuronal And Microglial Responses To Implanted Silicon Devices Through Immunohistochemistry And Clarity, Michael A. Leathers, Kevin J. Otto

The Summer Undergraduate Research Fellowship (SURF) Symposium

Brain computer interfaces (BCI’s) and implantable cortical devices have recently emerged in research as promising treatment methods for a variety of neurological problems such as motor dysfunction, memory loss, and sudden onset seizures. The number of people currently suffering from a loss of nervous system function as a result of neurodegenerative diseases or injury creates a need for reliable neural prostheses. The autoimmune response of the Central Nervous System (CNS) when introduced with a foreign object such as an electrode shank quickly impedes signal strength and degrades the functional life of the device. Two different experimental methods were used to …


The Effects Of Exogenous Extracellular Matrix And Substrate Stiffness On Mouse Tendon Cells In Vitro, Caleb J. Mcdaniel, Sarah Calve Oct 2013

The Effects Of Exogenous Extracellular Matrix And Substrate Stiffness On Mouse Tendon Cells In Vitro, Caleb J. Mcdaniel, Sarah Calve

The Summer Undergraduate Research Fellowship (SURF) Symposium

To improve the treatment of musculoskeletal injuries, a better understanding of the transitional environment in which progenitor cells form mature musculoskeletal constructs is necessary. This need arises because injury repair requires restructuring of tissue, similar to the initial tissue construction that occurs during embryonic development by progenitor cells. Differences in both the biochemical and mechanical environments between a transitional and a differentiated state are known to take place, but how these differences affect cell behavior had not yet been characterized in mammalian tendon cells. In order to investigate this, we have determined the effects of exogenous extracellular matrix and the …


Inkjet Printing Of Polarized Yeast Cells, Xiuyuan Yang, Kari Clase Oct 2013

Inkjet Printing Of Polarized Yeast Cells, Xiuyuan Yang, Kari Clase

The Summer Undergraduate Research Fellowship (SURF) Symposium

The motivation is to applying engineering knowledge to develop 3D bio-printing in inkjet printer (first stage--monolayer). To achieve the goal, there are three problems to solve. First, we have to figure out regulation of growth of target cells; inability to regulate the location and pattern of growing cells make us even unable to build 3D printer in the direct way. Second problem is how to protect of yeast cells from high temperature and viscous force when printing. The third issue is how to modify the inkjet printer especially the feeding system in order to implement printing on other materials rather …


Structural And Functional Characterization Of The Endosome-Associated Deubiquitinating Enzyme Amsh, Christopher Williamson Davies Oct 2013

Structural And Functional Characterization Of The Endosome-Associated Deubiquitinating Enzyme Amsh, Christopher Williamson Davies

Open Access Dissertations

The endosomal sorting complexes required for transport (ESCRT) machinery is a ubiquitin-dependent molecular mechanism made of up of four individual complexes: ESCRT-0, -I, -II, III, that is necessary for regulating the degradation of cell surface receptors directed towards the lysosome. Not only are the ESCRTs implicated in endosomal sorting and trafficking of proteins, its members also have roles in other important biological processes such as: cytokinesis, HIV budding, transcriptional regulation, and autophagy. As a function of its involvement in several processes throughout the cell, the ESCRT machinery is implicated in a wide variety of diseases including cancer, neurological disease, bacterial …


Smooth Muscle-Specific Removal Of Brain-Derived Neurotrophic Factor Results In Increased Vagal Afferent Innervation To The Intestine And Increased Satiation In Mice, Jessica Erin Biddinger Oct 2013

Smooth Muscle-Specific Removal Of Brain-Derived Neurotrophic Factor Results In Increased Vagal Afferent Innervation To The Intestine And Increased Satiation In Mice, Jessica Erin Biddinger

Open Access Dissertations

Vagal afferents transmit signals regarding food-derived stimuli in the gastrointestinal (GI) tract to the brain. Vagal mechanoreceptors called intraganglionic laminar endings (IGLEs) innervate the smooth muscle wall of GI organs and detect stretch and tension to regulate GI reflexes and satiation. Brain-derived neurotrophic factor (BDNF) is expressed in the smooth muscle of developing GI organs when vagal afferents from the nodose ganglion begin to innervate the GI tract. Therefore, it was hypothesized BDNF is necessary for development of vagal afferents that innervate this tissue. Targeted smooth muscle-specific BDNF homozygous knockout (BDNF SM -/-) mice were generated and .vagal afferent innervation …


Environmental Tradeoffs In Bioenergy Production And Agricultural Practices, Alicia Lynn English Oct 2013

Environmental Tradeoffs In Bioenergy Production And Agricultural Practices, Alicia Lynn English

Open Access Dissertations

The focus of this dissertation is the environmental tradeoffs of stover removal within the Corn Belt. The environmental tradeoffs considered are mainly concerned with managing soil erosion and soil quality. The analysis layers soil characteristics, management strategies and per acre costs using an integrated RUSLE2/WEPS model and an economic optimization model to illuminate a lower bound supply response. Different assumptions were tested in regards to sustainability, prices, and market integration for five states and 18,760 soil types throughout the Corn Belt. Sustainability was defined to limit soil erosion from wind and water to 5 tons/acre/year and the soil organic matter …


Effects Of Hearing Aid Amplification On Robust Neural Coding Of Speech, Jonathan Daniel Boley Oct 2013

Effects Of Hearing Aid Amplification On Robust Neural Coding Of Speech, Jonathan Daniel Boley

Open Access Dissertations

Hearing aids are able to restore some hearing abilities for people with auditory impairments, but background noise remains a significant problem. Unfortunately, we know very little about how speech is encoded in the auditory system, particularly in impaired systems with prosthetic amplifiers. There is growing evidence that relative timing in the neural signals (known as spatiotemporal coding) is important for speech perception, but there is little research that relates spatiotemporal coding and hearing aid amplification.

This research uses a combination of computational modeling and physiological experiments to characterize how hearing aids affect vowel coding in noise at the level of …


Brain Bioavailability Of Polyphenols: Implications For Delivery Of Brain Health Benefits, Tzu-Ying Chen Oct 2013

Brain Bioavailability Of Polyphenols: Implications For Delivery Of Brain Health Benefits, Tzu-Ying Chen

Open Access Dissertations

Consumption of fruits and vegetables has been associated with neuroprotection and cognitive benefits throughout the life span. These associations have sparked interest in plant-derived polyphenols as biologically active agents with potential for targeting brain benefits. However, little is known regarding the ability of the polyphenols or their metabolites from polyphenol-rich products to cross the blood-brain-barrier, and be available for biological action. Furthermore, additional insight is needed on factors affecting the absorption and brain distribution of polyphenol metabolites in vivo. To fill gap in current knowledge, this thesis will focus on the effects of diabetogenic diet and diabetic state which have …


Reasoning Across Language And Vision In Machines And Humans, Andrei Barbu Oct 2013

Reasoning Across Language And Vision In Machines And Humans, Andrei Barbu

Open Access Dissertations

Humans not only outperform AI and computer-vision systems, but use an unknown computational mechanism to perform tasks for which no suitable approaches exist. I present work investigating both novel tasks and how humans approach them in the context of computer vision and linguistics. I demonstrate a system which, like children, acquires high-level linguistic knowledge about the world. Robots learn to play physically-instantiated board games and use that knowledge to engage in physical play. To further integrate language and vision I develop an approach which produces rich sentential descriptions of events depicted in videos. I then show how to simultaneously detect …


Characterization Of The Specificity And Functions Of The Protein Phosphatase Cdc14, Christie Eissler Oct 2013

Characterization Of The Specificity And Functions Of The Protein Phosphatase Cdc14, Christie Eissler

Open Access Dissertations

Protein phosphorylation is perhaps the most ubiquitous posttranslational modification in eukaryotes and recent studies suggest that upwards of 75% of human proteins are phosphorylated. Many proteins are phosphorylated at multiple sites, often controlled by multiple kinases and phosphatases. Multisite phosphorylation can differentially affect the functional and regulatory cellular outcomes. For example, dephosphorylation of a protein at a particular site may inhibit nuclear localization of a protein while dephosphorylation of a different site may be necessary for enzymatic activation of a protein. Thus, multisite protein phosphorylation can complicate our understanding of the biological significance and the functional consequences of protein phosphorylation. …


Using X-Ray Imaging Techniques To Determine Density Of Foods, Shivangi Mohan Kelkar Oct 2013

Using X-Ray Imaging Techniques To Determine Density Of Foods, Shivangi Mohan Kelkar

Open Access Dissertations

Density depends on the experimental technique and structural properties of food. True, apparent and bulk are different types of densities. For porous foods such as baked food products and complex food systems, accurate measurement of density is challenging. Empirical correlations dependent on composition and temperature exist to calculate true density. Thus if composition and apparent density are known, porosity can be calculated, porosity = [1 - (apparent density/ true density)]. Various non-destructive diagnostic tools have been employed to study food microstructure. Among these, computed tomography (CT) and digital radiography (DR) utilizing x-ray imaging showed greater capability for evaluation of food …