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Full-Text Articles in Life Sciences

Insects And The Evolution Of Developmental Pathways: Functional Analysis Of Genetic Sex Determination Mechanisms In Oncopeltus Fasciatus, Josefine Just Jan 2019

Insects And The Evolution Of Developmental Pathways: Functional Analysis Of Genetic Sex Determination Mechanisms In Oncopeltus Fasciatus, Josefine Just

Honors Theses

Natural selection alters genetic pathways over evolutionary time. However, different pathways have been shown to maintain mutations at varying rates, leading to different levels of conservation across developmental pathways. Sex determination pathways, in particular, show vast diversity across animals despite the fundamental conservation of biological sex itself. Here, I investigated the sex determination pathway of the hemimetabolous insect, Oncopeltus fasciatus. The large milkweed bug, O. fasciatus, is part of the order Hemiptera, which provides a relevant outgroup study to other insects in which sex determination has been studied to date. I studied three sex determination genes, intersex, fruitless, and three ...


Finding Aid To The Collection Of Victoria Sackville-West Materials., Victoria Sackville-West, Colby College Special Collections Jan 2018

Finding Aid To The Collection Of Victoria Sackville-West Materials., Victoria Sackville-West, Colby College Special Collections

Finding Aids

The collection contains 27 letters and 4 greeting cards of personal correspondence written between 1947-1961, from V. Sackville-West at her home at Sissinghurst Castle in Kent, U.K., to Grace Mountcastle Martin in Stillwater, Oklahoma. Many of the letters convey the author's thanks for shipments of sugar and soap during times of rationing in the U.K.

V. [Victoria or "Vita"] Sackville-West, English poet, novelist, socialite and suffragette, was born in 1892 at her family's estate at Knole in Kent. Privately educated, she began writing poetry at age 11, and had produced 8 novels and 5 plays by ...


Finding Aid To The Collection Of Celia Thaxter Materials, Celia Thaxter, Colby College Special Collections Jan 2018

Finding Aid To The Collection Of Celia Thaxter Materials, Celia Thaxter, Colby College Special Collections

Finding Aids

Celia Laighton Thaxter, 1835-1894, was an American poet and prose writer. Born Celia Laighton in Portsmouth, N.H., she spent her childhood on White Island Lighthouse, part of Isles of Shoals, and Appledore Island. At 16 she married Levi Thaxter and had three sons, Karl, John, and Roland. The family spent winters on the mainland in Massachusetts, where Celia felt imprisoned by domestic duties in a city house. Her first poem, "Land-locked," was published in 1860 and was an immediate success. Soon she became widely published, with poems appearing in Harper's, Scribner's, and the Atlantic. With the means ...


Finding Aid To The Collection Of Louise Helen Coburn Materials, Louise Helen Coburn, Colby College Special Collections Jan 2018

Finding Aid To The Collection Of Louise Helen Coburn Materials, Louise Helen Coburn, Colby College Special Collections

Finding Aids

Louise Helen Coburn was born in Skowhegan, Maine on September 1, 1856, daughter of Stephen Coburn and Helen Sophia Miller. Coburn was Colby's second female graduate (after Mary Low Carver) in 1877, and graduated with Phi Beta Kappa honors. She also later received an honorary Litt. D. degree from Colby in 1914. Coburn's family was deeply tied to Colby College. Her father Stephen graduated in 1839, and the Coburn family was critical to Colby's early development as benefactors. Coburn was a co-founder, along with Mary Low Carver and others, of the Sigma Kappa Sorority. Coburn also later ...


The Effects Of Nutrient Limitation On Toxin Production For The Harmful Algal Bloom Species, Pseudo-Nitzschia, In The Gulf Of Maine, Julia M. Park Jan 2018

The Effects Of Nutrient Limitation On Toxin Production For The Harmful Algal Bloom Species, Pseudo-Nitzschia, In The Gulf Of Maine, Julia M. Park

Honors Theses

Pseudo-nitzschia is a pennate marine diatom that produces the neurotoxin domoic acid (DA). Domoic acid accumulates in the digestive tract of filter feeders and becomes concentrated at higher trophic levels. When DA concentrations reach critical levels, consumption of toxic shellfish can induce a condition known as Amnesic Shellfish Poisoning (ASP), which has been responsible for the deaths of marine mammals, seabirds and humans. This study worked to respond to a toxic Pseudo-nitzschia bloom in the Gulf of Maine during the fall of 2016, with the goal of quantifying and identifying Pseudo-nitzschia spp. in the bloom region and to determine the ...


Investigating Phosphorylation Patterns And Their Effect On The Activity Of Transcription Factor Taabf1 In Imbibing Cereal Grains, Grace Uwase Jan 2018

Investigating Phosphorylation Patterns And Their Effect On The Activity Of Transcription Factor Taabf1 In Imbibing Cereal Grains, Grace Uwase

Honors Theses

The wheat transcription factor TaABF1 plays an important role in hormone-mediated regulation of seed dormancy and germination of cereal grains. Evidence shows that TaABF1 activity is regulated by phosphorylation, and previous work in our lab showed that when serine residues in its conserved regions; S36, S37, S113, S115 were altered to phosphomimetic aspartate, the 4xD TaABF1 mutant had increased activity as a transcription factor. However, when only S113 was altered, TaABF1’s activity was greatly reduced. The work presented here explored whether the S36D/S37D/S115D mutant would have stronger activity than the 4xD mutant. Using the particle bombardment technique ...


Haloferax Volcanii For Carotenoid Production, Erika Smith Jan 2018

Haloferax Volcanii For Carotenoid Production, Erika Smith

Honors Theses

Carotenoids are used as natural colorants and have been shown to have numerous health benefits, making these molecules highly desirable in the aquaculture, pharmaceutical, and nutraceutical markets. There is increasing consumer demand for the natural synthesis of carotenoids, but current methods are limited by the cost and difficulty of extraction from organisms. The halophilic archaeon Haloferax volcanii is amenable to extraction and has an endogenous carotenoid biosynthetic pathway that culminates in the accumulation of the carotenoid bacterioruberin; however, H. volcanii also synthesizes important precursors that can be converted into more highly-desired carotenoids, such as β-carotene and astaxanthin, in the presence ...


Disc1 Knockout Rats Reveal Sexually Dimorphic Patterns Of Impairment Across Development, Stephanie S. Desrochers Jan 2018

Disc1 Knockout Rats Reveal Sexually Dimorphic Patterns Of Impairment Across Development, Stephanie S. Desrochers

Honors Theses

Schizophrenia is a chronic disorder characterized by three symptom categories: positive (hallucinations, delusions), negative (anhedonia, anxiety), and cognitive (sensory processing and memory deficits). We worked with a biallelic deletion of the Disrupted-in-schizophrenia-1 (DISC1) gene in Sprague-Dawley rats to facilitate our understanding of the biological bases of schizophrenia. Mutations of DISC1 are associated with a higher prevalence of schizophrenia. Adult DISC1 knockout, compared to wildtype, rats display features of schizophrenia-like outcomes in rodent models. The present study investigated the progression of the cognitive symptom deficits in prepulse inhibition (PPI), assessing animals at postnatal days 17 (pre-weaning), 26 (post-weaning), 39 (adolescent), and ...


Big Data: Computational Biology Opens A New Window On The World's Challenges For Colby Scientists, Kate Carlisle Oct 2017

Big Data: Computational Biology Opens A New Window On The World's Challenges For Colby Scientists, Kate Carlisle

Colby Magazine

"What makes us 'us' and not a plant? Not a bacteria, or a virus," asks Andrea Tilden, the J. Warren Merrill Associate Professor of Biology and a genomics expert. "Any one genome has six thousand novels worth of information. Computational biology is the tool we use to read them."


Collaboration: Professor And Former Protégé Are Finding Answers To Nature's Questions, Gerry Boyle Oct 2017

Collaboration: Professor And Former Protégé Are Finding Answers To Nature's Questions, Gerry Boyle

Colby Magazine

Biologist Dave Angelini and collaborator Will Simmons '17J have published findings of their three-year study of the effect of pesticides on bumblebees and hope the results will have the scientific community looking for new solutions to the problem.


Science Phobic?: Professor Frank Fekete Can Fix That - And, Perhaps, Some Global Problems, Abukar Adan Oct 2017

Science Phobic?: Professor Frank Fekete Can Fix That - And, Perhaps, Some Global Problems, Abukar Adan

Colby Magazine

"It shouldn't be a surprise. Of any subdiscipline in biology, microbiology is the most relevant to my students' lives because everyone is concerned about his or her health." - Frank Fekete, professor of biology


Snap, Crackle, Crunch: For This Team Of Food Visionaries, Insects Are The Key To Feeding The World, Susan Abram Oct 2017

Snap, Crackle, Crunch: For This Team Of Food Visionaries, Insects Are The Key To Feeding The World, Susan Abram

Colby Magazine

For most people, a cricket's chirp is the song of summer. But for a multidisciplinary team of Colby alumni, the uninhibited chorus that comes from the insects marks a leap towards the future of sustainable food systems.


The Impact Weather Has On Nyc Citi Bike Share Company Activity, Mark Martinez Jul 2017

The Impact Weather Has On Nyc Citi Bike Share Company Activity, Mark Martinez

Journal of Environmental and Resource Economics at Colby

This paper seeks to figure out the effect weather has on individuals’ behavior. A more focused approach to determining this effect is seeing how different weather conditions ranging from the temperature, the precipitation, the amount of inches of snowfall and the wind speed effect the ridership of Citi Bikes throughout all four seasons. The approach of this research paper is using data from the National Climatic Data Center that focuses in on the weather found in Manhattan, New York and correlates each of the weather conditions to the total number of trips per day that is provided by the Citi ...


Electricity Demand Due To Policy Change In The U.K., Kevin W. Doherty Jul 2017

Electricity Demand Due To Policy Change In The U.K., Kevin W. Doherty

Journal of Environmental and Resource Economics at Colby

This paper examines United Kingdom Electricity Demand with regards to the Climate Change Act, which was enacted in November of 2008. Through actual demand data obtained from Nationalgrid, a U.K. based gas and electric utility company, this paper seeks to find out if the Climate Change Act has started to achieve its goal of reducing carbon emissions by looking at trends of electricity demand. Burning fossil fuels to produce electricity is a major contributor to global warming in the U.K. and policies enacted do not always live up to their ultimate goals. This paper tests how on track ...


The Demographic Drivers Of California’S Environmental Voting, Lukas Yasuda Jul 2017

The Demographic Drivers Of California’S Environmental Voting, Lukas Yasuda

Journal of Environmental and Resource Economics at Colby

This study examines the demographics of California’s 53 congressional districts and the relationship with the voting patterns on three environmentally focused propositions in the 2008 and 2010 elections. Previous literature on the topic is mixed as some studies suggest that select attributes are found among environmental voting centers, yet other research describes the relationship as more complex than simple characteristics. Previous literature on the topic is mixed, with some studies suggesting that select attributes are found among environmental vote support hubs, whereas alternative research suggests the problem is more complex than simple characteristics. I collected data on income, education ...


How Individuals React To Smog Alerts In Beijing --Evidence From Beijing Subway Volume, Hanjing Shi Jul 2017

How Individuals React To Smog Alerts In Beijing --Evidence From Beijing Subway Volume, Hanjing Shi

Journal of Environmental and Resource Economics at Colby

This paper is going to find out the impact of smog alerts on individuals’ outdoor activities in Beijing. I use the subway volume to represent the outdoor activities. There are four levels of smog alerts in Beijing – blue, yellow, orange, and, red. The blue one is the lowest, and the red one is the highest. People in Beijing in all do not react to smog alerts in all statistically significant both on working days and weekends. But when combine orange alerts and red alerts together, the results show that people react to severe alerts differently during non-weekend days and weekend ...


The Effects From Public Transportation On Property Values: A Closer Look At Scituate, Hanover, And Norwell, Massachusetts, Alexandra Taylor Perticone, Christine S. Coveney Jul 2017

The Effects From Public Transportation On Property Values: A Closer Look At Scituate, Hanover, And Norwell, Massachusetts, Alexandra Taylor Perticone, Christine S. Coveney

Journal of Environmental and Resource Economics at Colby

Prior studies have expressed the value of location in real estate, but more recent studies have explored the influence that public transportation has had on housing prices. Access to public transportation is understood to increase the value of homes. Easier access to public transportation allows for shorter and more convenient commutes into or within cities. However, other studies have found that proximity to public transportation can also have adverse effects on property values. This paper investigates whether the implementation of the Greenbush Commuter line in Massachusetts in October 2007 increased the housing prices in Scituate, Ma--the furthest town from the ...


Invited Introduction To Jerec, Matthew Kahn Jul 2017

Invited Introduction To Jerec, Matthew Kahn

Journal of Environmental and Resource Economics at Colby

No abstract provided.


Welcome By The Editor, Nathan W. Chan Jul 2017

Welcome By The Editor, Nathan W. Chan

Journal of Environmental and Resource Economics at Colby

No abstract provided.


Crops And Controversy: Industry’S Role In The Gmo Debate, Carina Wallack Jan 2017

Crops And Controversy: Industry’S Role In The Gmo Debate, Carina Wallack

Honors Theses

The use of genetically modified crops (also called GM crops, genetically modified organisms, or GMOs for short) has become a highly contested issue. New genetic modification technologies offer a variety of advantages for improving agricultural efficiency. However, some scientists argue that the safety testing conducted thus far does not provide enough information and worry about possible health and ecological risks. Private industry sponsors a great deal of research on genetically modified crops. As the international controversy regarding the use of GMOs has unfolded, the very companies responsible for commercializing genetically modified crops have gained substantial influence in the resulting scientific ...


Temporal Changes In The Larval Placopecten Magellanicus Population In A Small-Scale Fishery Closure Area In Coastal Maine, Usa, Jessica P. Batchelder Jan 2017

Temporal Changes In The Larval Placopecten Magellanicus Population In A Small-Scale Fishery Closure Area In Coastal Maine, Usa, Jessica P. Batchelder

Honors Theses

The Midcoast Maine Collaborative Scallop Project was established in 2013 by fishers, scientists, and policy makers to determine if a small-scale closure area could restore the local Atlantic sea scallop (Placopecten magellanicus) population to an area in coastal Maine that previously supported high scallop densities. These stakeholders established a three by one mile closure area in the Lower Muscle Ridge Channel to assess the response of the adult and larval scallop populations. Understanding the larval dynamics in a closure area is key to evaluating the recovery potential of the population and for future population stock levels. This study seeks to ...


Vein Patterning During Juvenile Wing Development In Oncopeltus Fasciatus And Jadera Haematoloma, William R. Simmons Jan 2017

Vein Patterning During Juvenile Wing Development In Oncopeltus Fasciatus And Jadera Haematoloma, William R. Simmons

Honors Theses

Wings are a defining characteristic of all pterygote insects and are agreed to originate from a single common winged ancestor. However, essentially nothing is known about the molecular mechanisms that regulate wing development and patterning outside of Endopterygota, and the vast majority of this knowledge comes solely from Drosophila melanogaster. There is reason to suspect that the drastic developmental differences that exist between Endopterygota and Exopterygota have resulted in changes in the mechanisms, timings, or even genes that govern wing development. This study examined the roles of several genes known to be involved in D. melanogaster wing development and patterning ...


Protein Kinase Activity Toward Taabf1 In Imbibing Grains, Taylor P. Enrico Jan 2017

Protein Kinase Activity Toward Taabf1 In Imbibing Grains, Taylor P. Enrico

Honors Theses

The hormones gibberellin and abscisic acid are essential for plant responses to changing environmental conditions, and can send opposing signals. In wheat, the transcription factor TaABF1 plays an important role at the intersection of a gibberellin-induced/abscisic acid-suppressed pathway. When gibberellin dominates, the GA-induced gene, Amy32b, is transcribed. When abscisic acid is dominant, TaABF1 is active and it downregulates GA-induction of Amy32b, while promoting ABA-induced transcription of the gene HVA1. The activity of TaABF1 is thought to be regulated by post-translational phosphorylation at key serine residues. In this study, to determine TaABF1 phosphorylation by wheat kinases, we purified recombinant histidine ...


Examining Interactions Between Opsins And Carotenoid Biosynthetic Proteins In Halophilic Archaea, Alexandru M. Plesa Jan 2017

Examining Interactions Between Opsins And Carotenoid Biosynthetic Proteins In Halophilic Archaea, Alexandru M. Plesa

Honors Theses

Organisms have evolved numerous specialized molecules for constantly responding to environmental changes. Examples of such molecules are the light-driven proton-pump rhodopsins, such as bacteriorhodopsin (BR) and cruxrhodopsin (cR), and the carotenoid pigments, such as retinal and bacterioruberin. In halophilic Archaea, retinal can covalently bind bacterioopsin (BO) and cruxopsin (CO) to form the corresponding protein complexes, and its biosynthesis is indirectly controlled by the activity of the lycopene elongase (Lye) enzyme, which converts lycopene, a retinal precursor, to a form of bacterioruberin. Interestingly, opsins were shown to inhibit the activity of Lye, thereby promoting retinal biosynthesis and indirectly regulating the apoprotein-cofactor ...


Sweating The Small Stuff: Linking Plankton To Climate Change, Brian Kim '18 Makes Conncetions, Stephen Collins Sep 2016

Sweating The Small Stuff: Linking Plankton To Climate Change, Brian Kim '18 Makes Conncetions, Stephen Collins

Colby Magazine

It takes an expansive mind to connect microscopic marine copepods (certain crustacean plankton) unwittingly chomping on floating microplastics with a bigger picture: the planet’s carbon pump and global climate change. But that’s what Brian Kim ’18 decided to investigate during Jan Plan, working with Bigelow Lab Senior Research Scientist David Fields.


New Clues To A Mass Extinction: Colby Geologist Robert Gastaldo And Student Researchers Unearth Evidence That Contradicts Prevailing Models About Ancient Die-Offs, Stephen Collins Mar 2016

New Clues To A Mass Extinction: Colby Geologist Robert Gastaldo And Student Researchers Unearth Evidence That Contradicts Prevailing Models About Ancient Die-Offs, Stephen Collins

Colby Magazine

Colby geologists are rewriting deep time history, altering the script of how scientists understand the mother of all mass extinctions—the End-Permian event that occurred approximately 252 million years ago. Or to suggest that they don’t, in fact, understand it.


They Care What You Eat: With Ingredients From The Classroom, Colbians Are Helping To Shape A New Maine, On The Farm, In The Sea, At The Restaurant Table, Gerry Boyle Mar 2016

They Care What You Eat: With Ingredients From The Classroom, Colbians Are Helping To Shape A New Maine, On The Farm, In The Sea, At The Restaurant Table, Gerry Boyle

Colby Magazine

With ingredients from the classroom, Colbians are helping to shape a new Maine, on the farm, in the sea, at the restaurant table.


The Real Footprint Of Electric Vehicles, And What That Could Mean For Our Future, Krista Brown Jan 2016

The Real Footprint Of Electric Vehicles, And What That Could Mean For Our Future, Krista Brown

Journal of Environmental and Resource Economics at Colby

This paper looks at the impact of electric vehicles on CO2 emissions specifically based on the type of electricity used in each New England state analyzed. The research looks at the question of whether or not emissions will in fact be lowered as electric cars start to take the majority of vehicles used instead of the conventional cars that take up a much larger percent of the motor vehicles used today. Taking into account the use of electricity and how many sources of electricity also release a substantial amount of emissions, we see how valid the public opinion of electric ...


The Effect Of The Deer Population On The Number Of Car Accidents, Timothy J. Hallock Jr Jan 2016

The Effect Of The Deer Population On The Number Of Car Accidents, Timothy J. Hallock Jr

Journal of Environmental and Resource Economics at Colby

This paper examines the relationship between the deer population and the number of car accidents in New York State from 2002-2012. Data collected includes information on the amount of deer hunted, the number of car accidents, and the number of hunting permits issued. This paper also involves a county level analysis within New York State of 56 counties from 2007 - 2012. An important part of analysis of this paper is the examination of the Buck population vs. the Doe population on the number of car accidents. This is an important study because of its possible policy implications regarding the amount ...


The Effect Of Information On Avoidance Behavior And Bicycle Transportation: A Study Of “Spare The Air” And Bay Area Bikeshare, Paige W. Whistler Jan 2016

The Effect Of Information On Avoidance Behavior And Bicycle Transportation: A Study Of “Spare The Air” And Bay Area Bikeshare, Paige W. Whistler

Journal of Environmental and Resource Economics at Colby

This paper seeks to address the effect of “Spare the Air” pollution control alerts in the San Francisco Bay Area in California on the use of Bay Area BikeShare as a form of transportation. By observing the daily alerts on the duration of rides using BikeShare, this paper observes if STA ozone alerts are effective in changing human behavior. The results show that only as a subscriber to the BikeShare program and on an alert day does duration decrease whereas customers regardless of if it is an alert day will ride more often and at longer distances. The results contradict ...