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Articles 1141 - 1170 of 1541

Full-Text Articles in Life Sciences

Stomatal Conductance Trends Of The Jade Plant (Crassula Ovata) In Relation To Circadian Rhythm Entrainability, Katie Cahoon, Martin Garcia, Matthew Pierga Oct 2012

Stomatal Conductance Trends Of The Jade Plant (Crassula Ovata) In Relation To Circadian Rhythm Entrainability, Katie Cahoon, Martin Garcia, Matthew Pierga

Featured Research

The effect of an inverse light cycle on a Crassulacean acid metabolism (CAM) plant was observed in the study. CAM plants are unique in that they open their stomata at night in order to conserve water, an evolution that has come about because these plants primarily exist in very arid climates. By placing a plant in a chamber in which the lights could be programmed to turn on when it was dark out, and to turn off during normal daylight hours, the stomatal conductance of the leaves of a jade plant (Crassula ovata) were recorded several times a day over …


The Effect Of Dirt On Inhibition Of Light Absorption In Musa Leaves, Lorelle Knight, Alexis Carrington, Angela French, Roxanne Barker Oct 2012

The Effect Of Dirt On Inhibition Of Light Absorption In Musa Leaves, Lorelle Knight, Alexis Carrington, Angela French, Roxanne Barker

Featured Research

Dirt can be transported by wind, human activity and many other factors. It was hypothesized that dirt particles collected on leaves will decrease leaf reflectance and thus make the leaf less healthy. The rationale for this is that the more dirt present on the leaf, the more inhibited photons will be in reaching leaf pigments. The leaf will therefore be less healthy as it will be less able to perform photosynthesis. To test this hypothesis, eight leaf samples with varying amounts of dirt present, were collected from the plant, Musa. A Unispec spectrophotometer was used to test the reflectance of …


The Effect Of Riparian And Arid Environments On Stomatal Conductance In Baccharis Salicifolia And Heteromeles Arbutifolia, Danalit Rangel, Vicki Mac, Ariel Lan Oct 2012

The Effect Of Riparian And Arid Environments On Stomatal Conductance In Baccharis Salicifolia And Heteromeles Arbutifolia, Danalit Rangel, Vicki Mac, Ariel Lan

Featured Research

A riparian environment is characterized by higher moisture levels than an arid environment; therefore they have different species of plants that can adapt to their natural habitats. It is critical that we explore the characteristics plants have in relation to their native environments. We propose to test the hypothesis that Baccharis salicifolia would have a higher stomatal conductance rate to water vapor loss compared to Heteromeles arbutifolia because Baccharis salicifolia thrives in a riparian environment in which water abundance would increase stomatal opening thereby contributing to the greater conductance. Using the LI-6400, we measured the conductance rate, photosynthetic rate, CO2 …


A Comparison Of Brittlebush (Encelia Farinosa) Productivity And Health During Drought And Post Rainfall, Gabi Diciolli, Karre Lawson, Anders Reimer Oct 2012

A Comparison Of Brittlebush (Encelia Farinosa) Productivity And Health During Drought And Post Rainfall, Gabi Diciolli, Karre Lawson, Anders Reimer

Featured Research

Encelia farinosa is well adapted for drought tolerance as its leaves transform color based on water availability. We were puzzled by a question that any desert botanist must consider. How does the photosynthetic efficiency of E. farinosa fluctuate as it transitions from a state of drought to a state of soil saturation within a 72 hour period? In this experiment we looked at the effects of irrigation on the health and quantum yield of the brittlebush by looking at photosynthetic rates using the portable photosynthesis system LI-COR 6400 when applied to two leaves on a given plant and water potential …


Characterization Of The Stem Cell Niche In Drosophila Testes, Vittorio Mena Jr. Oct 2012

Characterization Of The Stem Cell Niche In Drosophila Testes, Vittorio Mena Jr.

Seton Hall University Dissertations and Theses (ETDs)

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Achieving High Accuracy Prediction Of Minimotifs, Tian Mi, Sanguthevar Rajasekaran, Jerlin Camilus Merlin, Michael R. Gryk, Martin Schiller Sep 2012

Achieving High Accuracy Prediction Of Minimotifs, Tian Mi, Sanguthevar Rajasekaran, Jerlin Camilus Merlin, Michael R. Gryk, Martin Schiller

Life Sciences Faculty Research

The low complexity of minimotif patterns results in a high false-positive prediction rate, hampering protein function prediction. A multi-filter algorithm, trained and tested on a linear regression model, support vector machine model, and neural network model, using a large dataset of verified minimotifs, vastly improves minimotif prediction accuracy while generating few false positives. An optimal threshold for the best accuracy reaches an overall accuracy above 90%, while a stringent threshold for the best specificity generates less than 1% false positives or even no false positives and still produces more than 90% true positives for the linear regression and neural network …


Endoplasmic Reticulum Involvement In Yeast Cell Death, Nicanor Austriaco Aug 2012

Endoplasmic Reticulum Involvement In Yeast Cell Death, Nicanor Austriaco

Biology Faculty Publications

Yeast cells undergo programed cell death (PCD) with characteristic markers associated with apoptosis in mammalian cells including chromatin breakage, nuclear fragmentation, reactive oxygen species generation, and metacaspase activation. Though significant research has focused on mitochondrial involvement in this phenomenon, more recent work with both Saccharomyces cerevisiae and Schizosaccharomyces pombe has also implicated the endoplasmic reticulum (ER) in yeast PCD. This minireview provides an overview of ER stress-associated cell death (ER-SAD) in yeast. It begins with a description of ER structure and function in yeast before moving to a discussion of ER-SAD in both mammalian and yeast cells. Three examples of …


Condensin Ii Promotes The Formation Of Chromosome Territories By Inducing Axial Compaction Of Polyploid Interphase Chromosomes, Christopher R. R. Bauer, Tom A. Hartl, Giovanni Bosco Aug 2012

Condensin Ii Promotes The Formation Of Chromosome Territories By Inducing Axial Compaction Of Polyploid Interphase Chromosomes, Christopher R. R. Bauer, Tom A. Hartl, Giovanni Bosco

Dartmouth Scholarship

The eukaryotic nucleus is both spatially and functionally partitioned. This organization contributes to the maintenance, expression, and transmission of genetic information. Though our ability to probe the physical structure of the genome within the nucleus has improved substantially in recent years, relatively little is known about the factors that regulate its organization or the mechanisms through which specific organizational states are achieved. Here, we show that Drosophila melanogaster Condensin II induces axial compaction of interphase chromosomes, globally disrupts interchromosomal interactions, and promotes the dispersal of peri-centric heterochromatin. These Condensin II activities compartmentalize the nucleus into discrete chromosome territories and indicate …


Sesquiterpene Synthase Gene And Protein, Joe Chappell, Bryan Greenhagen Jun 2012

Sesquiterpene Synthase Gene And Protein, Joe Chappell, Bryan Greenhagen

Plant and Soil Sciences Faculty Patents

The invention relates to sesquiterpene synthases and methods for their production and use. Particularly, the invention provides nucleic acids comprising the nucleotide sequence of citrus valencene synthase (CVS) which codes for at least one CVS. The invention further provides nucleic acids comprising the nucleotide sequence coding for amino acid residues forming the tier 1 and tier 2 domains of CVS. The invention also provides for methods of making and using the nucleic acids and amino acids of the current invention.


Minor Fibrillar Collagens, Variable Regions Alternative Splicing, Intrinsic Disorder, And Tyrosine Sulfation, Ming Fang, Reed B. Jacob, Owen Mcdougal, Julia Oxford Jun 2012

Minor Fibrillar Collagens, Variable Regions Alternative Splicing, Intrinsic Disorder, And Tyrosine Sulfation, Ming Fang, Reed B. Jacob, Owen Mcdougal, Julia Oxford

Biomedical Research Institute Publications and Presentations

Minor fibrillar collagen types V and XI, are those less abundant than the fibrillar collagens types I, II and III. The alpha chains share a high degree of similarity with respect to protein sequence in all domains except the variable region. Genomic variation and, in some cases, extensive alternative splicing contribute to the unique sequence characteristics of the variable region. While unique expression patterns in tissues exist, the functions and biological relevance of the variable regions have not been elucidated. In this review, we summarize the existing knowledge about expression patterns and biological functions of the collagen types V and …


Electrical Advantages Of Dendritic Spines, Allan T. Gulledge, Nicholas T. Carnevale, Greg J. Stuart Apr 2012

Electrical Advantages Of Dendritic Spines, Allan T. Gulledge, Nicholas T. Carnevale, Greg J. Stuart

Dartmouth Scholarship

Many neurons receive excitatory glutamatergic input almost exclusively onto dendritic spines. In the absence of spines, the amplitudes and kinetics of excitatory postsynaptic potentials (EPSPs) at the site of synaptic input are highly variable and depend on dendritic location. We hypothesized that dendritic spines standardize the local geometry at the site of synaptic input, thereby reducing location-dependent variability of local EPSP properties. We tested this hypothesis using computational models of simplified and morphologically realistic spiny neurons that allow direct comparison of EPSPs generated on spine heads with EPSPs generated on dendritic shafts at the same dendritic locations. In all morphologies …


Cloning And Characterization Of The Cell Wall Acting Enzyme Cd1034 From The Pathogen Clostridium Difficile, Zachary Suter Apr 2012

Cloning And Characterization Of The Cell Wall Acting Enzyme Cd1034 From The Pathogen Clostridium Difficile, Zachary Suter

Honors Projects in Science and Technology

The manifestation of multidrug resistance in bacteria over the past several decades has resulted in one of the foremost challenges in the management of infectious diseases. The question arises, “How do we address this growing problem?” One solution to stem the growing rise in antimicrobial resistance is to investigate new targets, while another approach is to re-examine classical antibacterial targets with a fresh perspective. The aim of this paper is to begin the process of antibacterial development for the pathogen Clostridium difficile by characterizing the cell wall acting glucosaminidase CD1034. It is inunderstanding how CD1034 functions biochemically that it can …


The Effects Of Dependent Infants On The Social Behavior Of Mantled Howler Monkeys (Alouatta Palliate), Keziah Katz Apr 2012

The Effects Of Dependent Infants On The Social Behavior Of Mantled Howler Monkeys (Alouatta Palliate), Keziah Katz

Honors Theses and Capstones

Six weeks of observation on eight groups of wild mantled howler monkeys revealed that the presence of a dependent infant alters the frequency of social interactions between a female with an infant and other adult monkeys. Males preferred to spend time with females without infants but still spent more time with females with infants than with males. Females without infants spent significantly less time with females with infants than with males or other females without infants and females with infants decreased their frequency of social interaction overall without preference for males, females or other females with infants.


Library Impact Statement For Nrs/Bio 417 Herpetology, Michael A. Cerbo Ii Mar 2012

Library Impact Statement For Nrs/Bio 417 Herpetology, Michael A. Cerbo Ii

Library Impact Statements

Library Impact Statement for NRU/BIO 417 Herpetology new course proposal. No new library resources are needed to support this course. Responding library faculty member: Michael A. Cerbo II. Requesting faculty member: Nancy E. Karraker.


Library Impact Statement For Nrs/Bio 517 Herpetology, Michael A. Cerbo Ii Mar 2012

Library Impact Statement For Nrs/Bio 517 Herpetology, Michael A. Cerbo Ii

Library Impact Statements

Library Impact Statement for NRS/BIO 517 Herpetology. No new library resources are needed to support this course. Responding library faculty member: Micael A. Cerbo II. Requesting faculty member: Nancy E. Karraker.


Reducing False-Positive Prediction Of Minimotifs With A Genetic Interaction Filter, Jerlin Camilus Merlin, Sanguthevar Rajasekaran, Tian Mi, Martin Schiller Mar 2012

Reducing False-Positive Prediction Of Minimotifs With A Genetic Interaction Filter, Jerlin Camilus Merlin, Sanguthevar Rajasekaran, Tian Mi, Martin Schiller

Life Sciences Faculty Research

Background

Minimotifs are short contiguous peptide sequences in proteins that have known functions. At its simplest level, the minimotif sequence is present in a source protein and has an activity relationship with a target, most of which are proteins. While many scientists routinely investigate new minimotif functions in proteins, the major web-based discovery tools have a high rate of false-positive prediction. Any new approach that reduces false-positives will be of great help to biologists.

Methods and Findings

We have built three filters that use genetic interactions to reduce false-positive minimotif predictions. The basic filter identifies those minimotifs where the source/target …


Library Impact Statement For Bio 501 Advanced Scientific Ethics, Michael A. Cerbo Ii Feb 2012

Library Impact Statement For Bio 501 Advanced Scientific Ethics, Michael A. Cerbo Ii

Library Impact Statements

Library Impact Statement for BIO 501 Advanced Scientific Ethics new course proposal. No new resources are required to support this course. Responding library faculty member: Michael A. Cerbo II. Requesting faculty member: Chris Lane.


Library Impact Statement For Bio 502 Advanced Scientific Communication, Michael A. Cerbo Ii Feb 2012

Library Impact Statement For Bio 502 Advanced Scientific Communication, Michael A. Cerbo Ii

Library Impact Statements

Library Impact Statement for BIO 502 Advanced Scientific Communication new course proposal. No new resources are needed to support this course. Responding library faculty member: Michael A. Cerbo II. Requesting faculty member: Chris Lane.


Library Impact Statement For Bio 553 Regulatory Processes In Eucaryotic Cells, Michael A. Cerbo Ii Jan 2012

Library Impact Statement For Bio 553 Regulatory Processes In Eucaryotic Cells, Michael A. Cerbo Ii

Library Impact Statements

Library Impact Statement for BIO 553 Regulatory Processes in Eucaryotic Cells new course proposal. No new library resources are needed to support this course. Responding library faculty member: Michael A. Cerbo II. Requesting faculty member: Joanna Norris.


Biology And Pathogenesis Of Acanthamoeba., Ruqaiyyah Siddiqui, Naveed Ahmed Khan Jan 2012

Biology And Pathogenesis Of Acanthamoeba., Ruqaiyyah Siddiqui, Naveed Ahmed Khan

Department of Biological & Biomedical Sciences

Acanthamoeba is a free-living protist pathogen, capable of causing a blinding keratitis and fatal granulomatous encephalitis. The factors that contribute to Acanthamoeba infections include parasite biology, genetic diversity, environmental spread and host susceptibility, and are highlighted together with potential therapeutic and preventative measures. The use of Acanthamoeba in the study of cellular differentiation mechanisms, motility and phagocytosis, bacterial pathogenesis and evolutionary processes makes it an attractive model organism. There is a significant emphasis on Acanthamoeba as a Trojan horse of other microbes including viral, bacterial, protists and yeast pathogens.


Library Impact Statement For Bio 485x Salt Marsh Ecology, Michael A. Cerbo Ii Jan 2012

Library Impact Statement For Bio 485x Salt Marsh Ecology, Michael A. Cerbo Ii

Library Impact Statements

Library Impact Statement for BIO 485X Salt Marsh Ecology new course proposal. No new library resources are needed to support this course. Responding library faculty member: Michael A. Cerbo II. Requesting faculty member: Serena Moseman-Valtierra.


Library Impact Statement For Bio 585x Salt Marsh Ecology, Michael A. Cerbo Ii Jan 2012

Library Impact Statement For Bio 585x Salt Marsh Ecology, Michael A. Cerbo Ii

Library Impact Statements

Library Impact Statement for BIO 585X Salt Marsh Ecology new course proposal. No new library resources are needed to support this course. Responding library faculty member: Michael A. Cerbo II. Requesting faculty member: Serena Moseman-Valtierra.


It’S My Body: The Biomedical Ethics Of Cell And Organ Harvest, Christina Perri Jan 2012

It’S My Body: The Biomedical Ethics Of Cell And Organ Harvest, Christina Perri

Common Reading Essay Contest Winners

First Place


The Effects Of Water Stress On Datura Wrightii, Tony Festa, Kristin Lapointe, Sara Tandon Jan 2012

The Effects Of Water Stress On Datura Wrightii, Tony Festa, Kristin Lapointe, Sara Tandon

Featured Research

The Santa Monica Mountains are home to a unique Mediterranean type ecosystem. Due to the effects of global warming and human disruption, the native species are beginning to decrease in population. It is imperative to observe and study the native species in order to preserve the local plant and animal life. This project focuses on the native flower Datura wrightii, specifically the causes of the opening and closing of its flowers. For Datura wrightii to be pollinated, it must be open. The results of this project will help to educate the public on how to sustain an environment in which …


Stem Mechanical Strength In Thinned Versus Non-Thinned Ceanothus Spinosus, Ksp, David J. Kang, Hannah Y. Choe, Melinda L. Marchiano Jan 2012

Stem Mechanical Strength In Thinned Versus Non-Thinned Ceanothus Spinosus, Ksp, David J. Kang, Hannah Y. Choe, Melinda L. Marchiano

Featured Research

What effect does the thinning of chaparral around building structures have on plant health? More specifically, does the thinning of Ceanothus spinosus influence mechanical strength? The ability of our native chaparral to withstand environmental factors, such as the Santa Ana winds, and overall health is directly related to plant strength. Seeking to answer these questions, we hypothesized that a difference in water potential between thinned and non-thinned chaparral affects the stem mechanical strength of the plants.We believed that thinned C. spinosus due to greater hydration will be mechanically stronger than non-thinned chaparral.The knowledge of what helps chaparral to be stronger …


The Differences In Vegetation Type On North And South-Facing Slopes, Andrew Villablanca, Katherine Mccabe, Daniel Galuhn Jan 2012

The Differences In Vegetation Type On North And South-Facing Slopes, Andrew Villablanca, Katherine Mccabe, Daniel Galuhn

Featured Research

Our project investigated the relationship between climate change and vegetation type conversion in the Santa Monica Mountains on north and south facing slopes. Our hypothesis is that with a shift in climate towards dryer, hotter, and longer summers, and shorter and dryer winters, we will see a shift in the density of native chaparral in the Santa Monica mountains, and possibly an influx of non-native species. We tested this hypothesis by choosing three study sites that were on north/south ridgelines to simulate a dryer, harsher climate (south) and a more temperate climate (north). Using the point-quarter method to measure the …


Exploring The Hydration Levels Of Malosma Laurina At Different Elevations On A Man-Made Trail, Eric S. Taylor, Brad J. Anderson, Brandon E. Stites Jan 2012

Exploring The Hydration Levels Of Malosma Laurina At Different Elevations On A Man-Made Trail, Eric S. Taylor, Brad J. Anderson, Brandon E. Stites

Featured Research

The purpose of this study is to examine the water potential of Malosma laurina at different elevations of a man made trail in the chapparal of the Santa Monica Mountains. Chaparral in the Santa Monica Mountains have been depleted because of human involvement effecting the chaparral ecosystem. Fire breaks and man made trails are a few of the major causes of the rapidly changing ecosystem and continues to cause stress among the plants. We are testing the effect that man made trails have on the water potential of Malosma laurina. This was measured by taking samples of Malosma laurina at …


A Comparison Of Water Potential And Mechanical Strength Of Tip And Base Leaves In Heteromeles Arbutifolia, Aaron Tsai, James Maynard Jan 2012

A Comparison Of Water Potential And Mechanical Strength Of Tip And Base Leaves In Heteromeles Arbutifolia, Aaron Tsai, James Maynard

Featured Research

Heteromeles arbutifolia, commonly known as, Hollywood, is a plant that is extremely common in the California Chaparral ecosystem. It was observed that with Hollywood, the leaves grow on the tips of the branches predominantly. However, there are leaves that grow on the base of the branches that appear to be equally as healthy. The purpose of this investigation was to determine whether the leaves that grow at the tips of the branches or at the base of the branches were better suited to benefit the rest of the plant. Our hypothesis was that the leaves at the tips of the …


Mechanical Strength And Hydration Level Of Heteromeles Arbutifola And Eriogonium Cinerium, Erin Hayes, Allison Naasz, Ariel Mangum Jan 2012

Mechanical Strength And Hydration Level Of Heteromeles Arbutifola And Eriogonium Cinerium, Erin Hayes, Allison Naasz, Ariel Mangum

Featured Research

The purpose of this study was to explore the hydration levels and mechanical strength of two species native to the same area: the dry Mediterranean region of the Santa Monica Mountains. The plants in this area must make adaptations to dry and arid climates, and We will compare how they stack up against each other in terms of drought resistance. Using Hollywood (heteromeles arbutifola) and Buckwheat (Eriogonium cinerium) we studied the different hydration levels and mechanical strengths and compared them. Both H. Arbutifola and the E. Cinerium are expected to mechanically stronger when hydrated.. We also expect the H. Arbutifola …


Chemotherapy: The Physiological Cost Of A Cure, Megan Ellis Jan 2012

Chemotherapy: The Physiological Cost Of A Cure, Megan Ellis

A with Honors Projects

This project focuses on the common long term side effects of cancer treatments, apart from cure. In addition to physiological function changes, it focuses on the chemical composition of chemotherapy drugs.