Pub Date : 2015-06-01DOI: 10.14434/IUJUR.V1I1.13735
C. Cardona
The goal of this project is to establish a novel design approach for the additive manufacturing of mechanical transmission systems. Our focus is the design and 3D printing of a harmonic drive. Harmonic drives use the elastic dynamics of metals to create an elliptical rotation, which is what conceives the reduction of speed of the outer piece. Additive manufacturing is used to achieve more complex and precise mechanical structures. Components of less complexity will be 3D printed with polymer and commercial parts will be purchased. There is a need for the creation of new plastics manufacturing processes that define and simplify the decision methods involved in the production. With this project, we will establish the process we consider best for plastic additive manufacturing. The decision of which parts are 3D printed or machined affects the harmonic drive’s cost and lead-time; therefore, several alternatives are systematically analyzed. The final bill of materials contains the list of commercial parts and 3D printed parts. When assembled, a functioning harmonic drive is produced. The final harmonic drive is experimentally tested to determine the life of its components when subjected to working loads. The methods used in this research include the part consolidation for the optimization of the system, transcription of 3D models to STL files that can be printed, polymer additive manufacturing and traditional quality control techniques to improve the design. Material models utilized in this project are commercial aluminum parts, 3D printer and plastic, and a low-voltage power motor. The complete set of results will give torque and speed reduction ratios that will be compared to those previously obtained by electronic simulations. This locates us a step ahead in the creation of an optimal process for additive manufacturing.
{"title":"Part Consolidation for Additive Manufacturing Demonstrated in the Design of a 3D-Printed Harmonic Drive","authors":"C. Cardona","doi":"10.14434/IUJUR.V1I1.13735","DOIUrl":"https://doi.org/10.14434/IUJUR.V1I1.13735","url":null,"abstract":"The goal of this project is to establish a novel design approach for the additive manufacturing of mechanical transmission systems. Our focus is the design and 3D printing of a harmonic drive. Harmonic drives use the elastic dynamics of metals to create an elliptical rotation, which is what conceives the reduction of speed of the outer piece. Additive manufacturing is used to achieve more complex and precise mechanical structures. Components of less complexity will be 3D printed with polymer and commercial parts will be purchased. There is a need for the creation of new plastics manufacturing processes that define and simplify the decision methods involved in the production. With this project, we will establish the process we consider best for plastic additive manufacturing. The decision of which parts are 3D printed or machined affects the harmonic drive’s cost and lead-time; therefore, several alternatives are systematically analyzed. The final bill of materials contains the list of commercial parts and 3D printed parts. When assembled, a functioning harmonic drive is produced. The final harmonic drive is experimentally tested to determine the life of its components when subjected to working loads. The methods used in this research include the part consolidation for the optimization of the system, transcription of 3D models to STL files that can be printed, polymer additive manufacturing and traditional quality control techniques to improve the design. Material models utilized in this project are commercial aluminum parts, 3D printer and plastic, and a low-voltage power motor. The complete set of results will give torque and speed reduction ratios that will be compared to those previously obtained by electronic simulations. This locates us a step ahead in the creation of an optimal process for additive manufacturing.","PeriodicalId":22986,"journal":{"name":"The Journal of Undergraduate Research","volume":"45 1","pages":"45-49"},"PeriodicalIF":0.0,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86311581","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-01DOI: 10.14434/IUJUR.V1I1.13516
Julie Y. Xu
Gene flow of a parasite is commonly contingent upon its most motile host’s dispersal rate. High gene flow can reduce local differentiation and potentially the rate of adaptation to local hosts (Blasco-Costa, Waters, & Poulin, 2011; Louhi, Karvonen, Rellstab, & Jokela, 2010). We investigated fine-scale spatial differentiation in a parasitic trematode ( Microphallus sp. ), which alternates between two hosts: a relatively sedentary invertebrate, a freshwater snail ( Potamopyrgus antipodarum ), and a highly motile vertebrate, a duck (Hechinger, 2012). In 2014, adult snails were sampled from 13 different sites around a New Zealand lake to determine the distribution of infection. Juvenile snails were also collected from these sites for experimental manipulation. Finally, parasite eggs were collected by sampling duck feces from a northern and southern site on the lake. Juvenile snails from each site were exposed to parasites from either the northern or southern source. The infection status of field-collected adults and experimental juveniles was determined by dissection. Given the close proximity between sites and the duck host’s strong dispersal ability, we predicted low spatial variation in infectivity of the two parasite sources. The results, however, indicate significant spatial variation in both host resistance and parasite infectivity. Though infection rates across host sites were significantly correlated, the two sources differed significantly in their infectivity to hosts from different sites. This result suggests that the two parasite sources are adapted to infect different hosts, indicating genetic differentiation of the parasite. In addition, the frequency of infection and resistance of the freshwater snail differed significantly between sites within close proximity to one another. Detection of strong variation indicates that dispersal of the vertebrate host does not prevent fine-scale spatial differentiation in this host-parasite system. Further studies are needed to investigate the forces that maintain the extensive spatial variation in disease observed.
{"title":"The Effect of Host’s Dispersal Ability on Fine-Scale Spatial Differentiation","authors":"Julie Y. Xu","doi":"10.14434/IUJUR.V1I1.13516","DOIUrl":"https://doi.org/10.14434/IUJUR.V1I1.13516","url":null,"abstract":"Gene flow of a parasite is commonly contingent upon its most motile host’s dispersal rate. High gene flow can reduce local differentiation and potentially the rate of adaptation to local hosts (Blasco-Costa, Waters, & Poulin, 2011; Louhi, Karvonen, Rellstab, & Jokela, 2010). We investigated fine-scale spatial differentiation in a parasitic trematode ( Microphallus sp. ), which alternates between two hosts: a relatively sedentary invertebrate, a freshwater snail ( Potamopyrgus antipodarum ), and a highly motile vertebrate, a duck (Hechinger, 2012). In 2014, adult snails were sampled from 13 different sites around a New Zealand lake to determine the distribution of infection. Juvenile snails were also collected from these sites for experimental manipulation. Finally, parasite eggs were collected by sampling duck feces from a northern and southern site on the lake. Juvenile snails from each site were exposed to parasites from either the northern or southern source. The infection status of field-collected adults and experimental juveniles was determined by dissection. Given the close proximity between sites and the duck host’s strong dispersal ability, we predicted low spatial variation in infectivity of the two parasite sources. The results, however, indicate significant spatial variation in both host resistance and parasite infectivity. Though infection rates across host sites were significantly correlated, the two sources differed significantly in their infectivity to hosts from different sites. This result suggests that the two parasite sources are adapted to infect different hosts, indicating genetic differentiation of the parasite. In addition, the frequency of infection and resistance of the freshwater snail differed significantly between sites within close proximity to one another. Detection of strong variation indicates that dispersal of the vertebrate host does not prevent fine-scale spatial differentiation in this host-parasite system. Further studies are needed to investigate the forces that maintain the extensive spatial variation in disease observed.","PeriodicalId":22986,"journal":{"name":"The Journal of Undergraduate Research","volume":"11 1","pages":"38"},"PeriodicalIF":0.0,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75176524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-01DOI: 10.14434/IUJUR.V1I1.13727
Kushal Shah
This paper explores people’s reception of and attitudes toward Rachel Carson’s Silent Spring , originally published in 1962. Research was conducted entirely through the lens of The New York Times ( NYT ) articles ranging from before the book’s publication to the present. The articles vary heavily in perspective, representing a range of views towards Carson’s vilification of both the pesticide industry and general American attitudes regarding environmental conservation. Articles from NYT represent public opinion well because the chosen articles come from views representing a variety of sources (corporations, scientists, book reviewers, historians, etc.) and perspectives ranging from maximum support to open criticism of the book. When observed over time, research into these articles tells the story of the change in acceptance of Silent Spring – how it has reached its current state of reverence and influence. This paper comprehensively examines a variety of articles regarding Silent Spring and America’s environmental efforts, tracking the change of general attitudes over the 50 years since its publication.
{"title":"Silent Spring and the New York Times: How Rachel Carson Won the Journey","authors":"Kushal Shah","doi":"10.14434/IUJUR.V1I1.13727","DOIUrl":"https://doi.org/10.14434/IUJUR.V1I1.13727","url":null,"abstract":"This paper explores people’s reception of and attitudes toward Rachel Carson’s Silent Spring , originally published in 1962. Research was conducted entirely through the lens of The New York Times ( NYT ) articles ranging from before the book’s publication to the present. The articles vary heavily in perspective, representing a range of views towards Carson’s vilification of both the pesticide industry and general American attitudes regarding environmental conservation. Articles from NYT represent public opinion well because the chosen articles come from views representing a variety of sources (corporations, scientists, book reviewers, historians, etc.) and perspectives ranging from maximum support to open criticism of the book. When observed over time, research into these articles tells the story of the change in acceptance of Silent Spring – how it has reached its current state of reverence and influence. This paper comprehensively examines a variety of articles regarding Silent Spring and America’s environmental efforts, tracking the change of general attitudes over the 50 years since its publication.","PeriodicalId":22986,"journal":{"name":"The Journal of Undergraduate Research","volume":"21 1","pages":"18-22"},"PeriodicalIF":0.0,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82474327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-01DOI: 10.14434/IUJUR.V1I1.13724
K. Antior, A. K. Pugh
Undergraduate research experiences have become a hallmark of excellence in degree programs in the science, technology, engineering and math fields, with indications that these experiences lay important groundwork for graduate education and practice in the field. In nursing, several schools offer undergraduate nursing research experiences, though there is scant research related to outcomes among nurses at the baccalaureate level. Since evidence-based practice (EBP) is becoming increasingly important in health care, the use of research-related skill sets has become more critical for practicing nurses. The benefits of undergraduate research experience have been inadequately studied and there have been no nursing studies on the impact of undergraduate nursing research experience on the practicing registered nurse. At a research intensive public university, a robust honors program exposes students to research throughout the baccalaureate degree, with student engagement in every step of the research process alongside faculty research mentors. The purpose of this study was to qualitatively explore the experiences and outcomes of participation in a significant undergraduate research project on the first few years of nursing practice as an RN. Data analysis was conducted using an open coding method to analyze the responses of the participants and aid in the process of identifying major themes that express the phenomenon. Through this approach a descriptive analysis of the experience of completing an undergraduate research project was completed, including the impact on the nursing practice and development of the participants in their early careers. The results suggest that extensive exposure to research in undergraduate schooling increases the level of self-confidence in the first nursing position. Participants also felt that they stood out from their peers. Other benefits include expanding knowledge regarding the research process, improving writing and public speaking skills, and advancing personal and professional development.
{"title":"The Experience of Completing an Undergraduate Nursing Honors Research Project on the First Professional Nursing Position","authors":"K. Antior, A. K. Pugh","doi":"10.14434/IUJUR.V1I1.13724","DOIUrl":"https://doi.org/10.14434/IUJUR.V1I1.13724","url":null,"abstract":"Undergraduate research experiences have become a hallmark of excellence in degree programs in the science, technology, engineering and math fields, with indications that these experiences lay important groundwork for graduate education and practice in the field. In nursing, several schools offer undergraduate nursing research experiences, though there is scant research related to outcomes among nurses at the baccalaureate level. Since evidence-based practice (EBP) is becoming increasingly important in health care, the use of research-related skill sets has become more critical for practicing nurses. The benefits of undergraduate research experience have been inadequately studied and there have been no nursing studies on the impact of undergraduate nursing research experience on the practicing registered nurse. At a research intensive public university, a robust honors program exposes students to research throughout the baccalaureate degree, with student engagement in every step of the research process alongside faculty research mentors. The purpose of this study was to qualitatively explore the experiences and outcomes of participation in a significant undergraduate research project on the first few years of nursing practice as an RN. Data analysis was conducted using an open coding method to analyze the responses of the participants and aid in the process of identifying major themes that express the phenomenon. Through this approach a descriptive analysis of the experience of completing an undergraduate research project was completed, including the impact on the nursing practice and development of the participants in their early careers. The results suggest that extensive exposure to research in undergraduate schooling increases the level of self-confidence in the first nursing position. Participants also felt that they stood out from their peers. Other benefits include expanding knowledge regarding the research process, improving writing and public speaking skills, and advancing personal and professional development.","PeriodicalId":22986,"journal":{"name":"The Journal of Undergraduate Research","volume":"54 1","pages":"40-44"},"PeriodicalIF":0.0,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84834523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-01DOI: 10.14434/IUJUR.V1I1.13739
Reshma Patel
Certain fungi can infect host plants and thereby cause sterility of the host. One such fungal parasite, Microbotryum violaceum (commonly known as anther smut), has host specificity to plants of the family Caryophyllaceae. Anther smut takes over the host reproductive system by inhibiting sex-organ development in flowers, and the plant produces fungal spores in place of its normal reproductive structures. Spores can then be spread to nearby hosts through wind and insect pollinators. This experiment focuses on Silene latifolia plant populations growing near Zagreb, Croatia. Our research tests for phenotypic differences between infected and healthy flowers. To do this, we measured the size of healthy and infected flowers of both sexes. Additionally, we observed the proportion of infected flowers over time on individuals to uncover temporal trends of the smut infection. We found that all flower parts, regardless of plant sex, are significantly smaller in smut-infected flowers. After observing proportions of infected flowers, we found that the ratio of infected to healthy flowers increased over time. Our findings suggest that smut infection of S. latifolia causes changes in plant energy allocation. We propose that the smaller flower size could be the result of increased energy needed for M. violaceum spore production. This hypothesis could be tested with additional research. The increasing proportion of smutty flowers on an infected individual over time is likely caused by the spread of the infection throughout the plant.
{"title":"Host Flower Infection of Silene latifolia by Microbotryum violaceum","authors":"Reshma Patel","doi":"10.14434/IUJUR.V1I1.13739","DOIUrl":"https://doi.org/10.14434/IUJUR.V1I1.13739","url":null,"abstract":"Certain fungi can infect host plants and thereby cause sterility of the host. One such fungal parasite, Microbotryum violaceum (commonly known as anther smut), has host specificity to plants of the family Caryophyllaceae. Anther smut takes over the host reproductive system by inhibiting sex-organ development in flowers, and the plant produces fungal spores in place of its normal reproductive structures. Spores can then be spread to nearby hosts through wind and insect pollinators. This experiment focuses on Silene latifolia plant populations growing near Zagreb, Croatia. Our research tests for phenotypic differences between infected and healthy flowers. To do this, we measured the size of healthy and infected flowers of both sexes. Additionally, we observed the proportion of infected flowers over time on individuals to uncover temporal trends of the smut infection. We found that all flower parts, regardless of plant sex, are significantly smaller in smut-infected flowers. After observing proportions of infected flowers, we found that the ratio of infected to healthy flowers increased over time. Our findings suggest that smut infection of S. latifolia causes changes in plant energy allocation. We propose that the smaller flower size could be the result of increased energy needed for M. violaceum spore production. This hypothesis could be tested with additional research. The increasing proportion of smutty flowers on an infected individual over time is likely caused by the spread of the infection throughout the plant.","PeriodicalId":22986,"journal":{"name":"The Journal of Undergraduate Research","volume":"378 1","pages":"37"},"PeriodicalIF":0.0,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74247421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-01DOI: 10.14434/IUJUR.V1I1.13714
Peyton J. Joachim
Host-parasite interactions are believed to exert strong selection in natural communities. Most notably, parasites should select for increased resistance in hosts, while hosts should select for increased infectivity in parasites (Koskella & Lively, 2007; Koskella, Vergara, & Lively, 2011; Lohse, Guiterrez, & Kaltz, 2006). Under this coevolutionary process, can host populations evolve resistance to their rapidly evolving parasite populations? This experiment was designed to determine if hosts rapidly adapt to resist parasites that are themselves under selection to infect their hosts. The New Zealand freshwater snail, Potamopyrgus antipodarum , is naturally infected by the trematode Microphallus . Microphallus is a castrating parasite and is thus likely to impose strong selection on its snail host (Hechinger, 2012). Snails and parasites were collected from a natural lake in summer 2013. These hosts constitute the parental generation of the experiment: they were either exposed to parasite eggs (Exposed) or not exposed (Control). Parental snails matured and reproduced over the course of a year. Their offspring were then exposed to parasites collected from the same lake in summer 2014. These parasites would have had one to a few additional generations of evolution relative to 2013 parasites. After parasite development (~3 months), the offspring were dissected to determine infection status and thereby their resistance to infection. The offspring of Control parents had a significantly higher mean infection rate (35%: less resistant) than the offspring of Exposed parents (30%: more resistant). This result indicates that increased resistance to parasitism evolved in a single host generation. Our finding provides evidence that a host population can rapidly evolve resistance to a parasite population that is itself rapidly co-evolving to infect its host. We predict that the evolution of host resistance would be far greater after multiple generations of parasite selection, and this could be the subject of future study.
{"title":"Evolution of Resistance in Potamopyrgus antipodarum","authors":"Peyton J. Joachim","doi":"10.14434/IUJUR.V1I1.13714","DOIUrl":"https://doi.org/10.14434/IUJUR.V1I1.13714","url":null,"abstract":"Host-parasite interactions are believed to exert strong selection in natural communities. Most notably, parasites should select for increased resistance in hosts, while hosts should select for increased infectivity in parasites (Koskella & Lively, 2007; Koskella, Vergara, & Lively, 2011; Lohse, Guiterrez, & Kaltz, 2006). Under this coevolutionary process, can host populations evolve resistance to their rapidly evolving parasite populations? This experiment was designed to determine if hosts rapidly adapt to resist parasites that are themselves under selection to infect their hosts. The New Zealand freshwater snail, Potamopyrgus antipodarum , is naturally infected by the trematode Microphallus . Microphallus is a castrating parasite and is thus likely to impose strong selection on its snail host (Hechinger, 2012). Snails and parasites were collected from a natural lake in summer 2013. These hosts constitute the parental generation of the experiment: they were either exposed to parasite eggs (Exposed) or not exposed (Control). Parental snails matured and reproduced over the course of a year. Their offspring were then exposed to parasites collected from the same lake in summer 2014. These parasites would have had one to a few additional generations of evolution relative to 2013 parasites. After parasite development (~3 months), the offspring were dissected to determine infection status and thereby their resistance to infection. The offspring of Control parents had a significantly higher mean infection rate (35%: less resistant) than the offspring of Exposed parents (30%: more resistant). This result indicates that increased resistance to parasitism evolved in a single host generation. Our finding provides evidence that a host population can rapidly evolve resistance to a parasite population that is itself rapidly co-evolving to infect its host. We predict that the evolution of host resistance would be far greater after multiple generations of parasite selection, and this could be the subject of future study.","PeriodicalId":22986,"journal":{"name":"The Journal of Undergraduate Research","volume":"3 3 1","pages":"35"},"PeriodicalIF":0.0,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82819839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-01DOI: 10.14434/IUJUR.V1I1.13265
A. Kerr
The 1864 massacre of Cheyenne and Arapaho Native Americans by a Colorado territorial militia regiment is investigated through a genocidal lens, both as a component of the larger destruction of Native American cultures and peoples by U.S. forces and in its own specific economic and ideological context. Using the work of many other scholars in the field of genocide studies and the established definition of genocide provided by the UN Convention on Genocide, this essay initially defines how the gradual dwindling of Native American populations from the onset of European colonization through the next three centuries can be viewed as genocide. Following this groundwork, the question of culpability for the massacre is brought forth and three main categories of suspects are identified: local government and military leaders, the White settler population of Colorado, and the U.S. federal government. All three potential areas of culpability are shown to possess varying degrees of responsibility in effecting the massacre. Upon conclusion of the investigation, there is a brief discussion of possible means of reconciliation accompanied by an examination of the nature of current reconciliation efforts.
{"title":"The Sand Creek Massacre","authors":"A. Kerr","doi":"10.14434/IUJUR.V1I1.13265","DOIUrl":"https://doi.org/10.14434/IUJUR.V1I1.13265","url":null,"abstract":"The 1864 massacre of Cheyenne and Arapaho Native Americans by a Colorado territorial militia regiment is investigated through a genocidal lens, both as a component of the larger destruction of Native American cultures and peoples by U.S. forces and in its own specific economic and ideological context. Using the work of many other scholars in the field of genocide studies and the established definition of genocide provided by the UN Convention on Genocide, this essay initially defines how the gradual dwindling of Native American populations from the onset of European colonization through the next three centuries can be viewed as genocide. Following this groundwork, the question of culpability for the massacre is brought forth and three main categories of suspects are identified: local government and military leaders, the White settler population of Colorado, and the U.S. federal government. All three potential areas of culpability are shown to possess varying degrees of responsibility in effecting the massacre. Upon conclusion of the investigation, there is a brief discussion of possible means of reconciliation accompanied by an examination of the nature of current reconciliation efforts.","PeriodicalId":22986,"journal":{"name":"The Journal of Undergraduate Research","volume":"28 1","pages":"6-12"},"PeriodicalIF":0.0,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72694350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-01DOI: 10.14434/IUJUR.V1I1.13740
Natalie A. Schumann
The National Geographic Magazine was first published in October 1888. Its mission statements both at the time of inception and in present day reflect an effort to bring the world to American readers, as well as its aim to educate and inform readers about other countries, species, and cultures. However, during the magazine’s first three decades in print, the United States underwent major changes and was rapidly developing into one of the world’s most powerful nations. National Geographic heavily covered three specific events during this time period: the Spanish-American War, the colonization of Cuba and the Philippines, and the creation of the first national parks. This coverage presented readers with strong nationalist opinions that broadcast views of American superiority. In this analysis of those early articles, the magazine’s nationalist sentiments become evident through primary and secondary examples, and its original and current mission statements are brought into question. The National Geographic readers know today was once a very different publication due to its reflection of current events and a changing American attitude toward other countries.
{"title":"Nationalism in National Geographic Magazine, 1888-1923","authors":"Natalie A. Schumann","doi":"10.14434/IUJUR.V1I1.13740","DOIUrl":"https://doi.org/10.14434/IUJUR.V1I1.13740","url":null,"abstract":"The National Geographic Magazine was first published in October 1888. Its mission statements both at the time of inception and in present day reflect an effort to bring the world to American readers, as well as its aim to educate and inform readers about other countries, species, and cultures. However, during the magazine’s first three decades in print, the United States underwent major changes and was rapidly developing into one of the world’s most powerful nations. National Geographic heavily covered three specific events during this time period: the Spanish-American War, the colonization of Cuba and the Philippines, and the creation of the first national parks. This coverage presented readers with strong nationalist opinions that broadcast views of American superiority. In this analysis of those early articles, the magazine’s nationalist sentiments become evident through primary and secondary examples, and its original and current mission statements are brought into question. The National Geographic readers know today was once a very different publication due to its reflection of current events and a changing American attitude toward other countries.","PeriodicalId":22986,"journal":{"name":"The Journal of Undergraduate Research","volume":"17 1","pages":"13-17"},"PeriodicalIF":0.0,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78407548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-01DOI: 10.14434/IUJUR.V1I1.13725
Samantha A. Klosak
Sexual reproduction is a very costly process: the growth rate of asexual lineages exceeds that of sexual lineages. Nonetheless, sex is prevalent in nature. The Red Queen Hypothesis argues that, because sex and recombination generate genetically variable offspring that may escape infection by coevolving parasites, parasites select for sex in hosts (Lively & Dybdahl, 2000). Our research directly tests if the Red Queen can explain the maintenance of sex in a natural population. This experiment focuses on a natural population of the snail Potamopyrgus antipodarum , which is native to New Zealand. Individuals of this species are either diploid and sexually reproducing or triploid and asexually reproducing (Lively & Osnas, 2006). This snail is naturally infected by the trematode parasite, Microphallus , which is sterilizing and thus exerts strong selection on its host. The Red Queen Hypothesis predicts that parasites should periodically increase the fitness of sexual relative to asexual individuals. We accordingly established mesocosms containing both sexual and asexual snails from the same natural population. Half of these mesocosms were exposed to parasites and the other half were not. These snails were then allowed to reproduce over the course of a year. We used flow cytometry to determine the frequency of diploids in the parents and the offspring, and thereby the fitness of sexual individuals in the presence and absence of parasites. Interestingly, we find that sexual individuals are currently more susceptible to parasites than are asexual individuals. In tanks in which sexual parents are relatively more infected, the frequency of sexual individuals declined significantly more in the offspring generation, indicating a fitness consequence of parasitism for sexual reproduction. Our findings suggest that parasite selection can indeed operate on reproductive mode. Moreover, our results are consistent with theory (King, Delph, Jokela, & Lively, 2009) and a prior field study in our system indicating that the direction of parasite selection is variable, such that parasites periodically select against sexual reproduction (Vergara, Lively, King, & Jokela, 2013). This current experiment will continue for multiple years in order to track the variation in parasite selection on sex through time.
{"title":"Parasite Selection and the Fitness of Sexual Reproduction","authors":"Samantha A. Klosak","doi":"10.14434/IUJUR.V1I1.13725","DOIUrl":"https://doi.org/10.14434/IUJUR.V1I1.13725","url":null,"abstract":"Sexual reproduction is a very costly process: the growth rate of asexual lineages exceeds that of sexual lineages. Nonetheless, sex is prevalent in nature. The Red Queen Hypothesis argues that, because sex and recombination generate genetically variable offspring that may escape infection by coevolving parasites, parasites select for sex in hosts (Lively & Dybdahl, 2000). Our research directly tests if the Red Queen can explain the maintenance of sex in a natural population. This experiment focuses on a natural population of the snail Potamopyrgus antipodarum , which is native to New Zealand. Individuals of this species are either diploid and sexually reproducing or triploid and asexually reproducing (Lively & Osnas, 2006). This snail is naturally infected by the trematode parasite, Microphallus , which is sterilizing and thus exerts strong selection on its host. The Red Queen Hypothesis predicts that parasites should periodically increase the fitness of sexual relative to asexual individuals. We accordingly established mesocosms containing both sexual and asexual snails from the same natural population. Half of these mesocosms were exposed to parasites and the other half were not. These snails were then allowed to reproduce over the course of a year. We used flow cytometry to determine the frequency of diploids in the parents and the offspring, and thereby the fitness of sexual individuals in the presence and absence of parasites. Interestingly, we find that sexual individuals are currently more susceptible to parasites than are asexual individuals. In tanks in which sexual parents are relatively more infected, the frequency of sexual individuals declined significantly more in the offspring generation, indicating a fitness consequence of parasitism for sexual reproduction. Our findings suggest that parasite selection can indeed operate on reproductive mode. Moreover, our results are consistent with theory (King, Delph, Jokela, & Lively, 2009) and a prior field study in our system indicating that the direction of parasite selection is variable, such that parasites periodically select against sexual reproduction (Vergara, Lively, King, & Jokela, 2013). This current experiment will continue for multiple years in order to track the variation in parasite selection on sex through time.","PeriodicalId":22986,"journal":{"name":"The Journal of Undergraduate Research","volume":"35 1","pages":"36"},"PeriodicalIF":0.0,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78671579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-01DOI: 10.14434/IUJUR.V1I1.13716
Gregory P. Welage
Aquatic ecosystems are created and dictated by their physical and chemical environment; when catastrophic events cause an ecosystem shift, such as the draining and refilling of a reservoir, the composition and quality of the ecosystem state can change based on the new physical and chemical environment. This research project examines the physical and chemical limnological changes in Griffy Lake, Bloomington, IN, after the complete drawdown of water for the purpose of dam reconstruction. After two years of sediment oxidation and terrestrial plant growth, the reservoir naturally refilled. The study summarizes recovery results from data collected on a monthly basis. The results focus on the variables of temperature, dissolved oxygen, alkalinity, pH, specific conductance, and nutrient concentrations. After analysis of the data, this project will allow for better understanding of the effects of complete drawdowns on abiotic variables. The work presented is part of a larger project that will examine how aquatic ecosystems recover and ecosystem states may shift within reservoirs after complete drawdowns. With more than 75,000 dams across the United States, many of which are approaching the end of their life spans, in the near future it is important to understand how such events affect the quality of the water, in addition to aquatic ecosystems.
{"title":"Abiotic Changes Within a Reservoir After a Complete Drawdown: A Case Study of Lake Griffy","authors":"Gregory P. Welage","doi":"10.14434/IUJUR.V1I1.13716","DOIUrl":"https://doi.org/10.14434/IUJUR.V1I1.13716","url":null,"abstract":"Aquatic ecosystems are created and dictated by their physical and chemical environment; when catastrophic events cause an ecosystem shift, such as the draining and refilling of a reservoir, the composition and quality of the ecosystem state can change based on the new physical and chemical environment. This research project examines the physical and chemical limnological changes in Griffy Lake, Bloomington, IN, after the complete drawdown of water for the purpose of dam reconstruction. After two years of sediment oxidation and terrestrial plant growth, the reservoir naturally refilled. The study summarizes recovery results from data collected on a monthly basis. The results focus on the variables of temperature, dissolved oxygen, alkalinity, pH, specific conductance, and nutrient concentrations. After analysis of the data, this project will allow for better understanding of the effects of complete drawdowns on abiotic variables. The work presented is part of a larger project that will examine how aquatic ecosystems recover and ecosystem states may shift within reservoirs after complete drawdowns. With more than 75,000 dams across the United States, many of which are approaching the end of their life spans, in the near future it is important to understand how such events affect the quality of the water, in addition to aquatic ecosystems.","PeriodicalId":22986,"journal":{"name":"The Journal of Undergraduate Research","volume":"126 1","pages":"24-33"},"PeriodicalIF":0.0,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85707836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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