2017 Projects
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Item Open Access Fruit cluster pruning of organic tomatoes(Colorado State University. Libraries, 2017) Mitchell, Brian A., authorThis research project examines the impact of fruit cluster pruning on three cultivars of tomato grown organically within a high tunnel. Each plant was trained to have a single leader. Two cluster pruning treatments and a control were used to study the effects on limiting fruits per cluster on yield, marketability, and quality. The experiment was replicated twice, in 2016 and 2017, at Colorado State University’s certified organic farmland located at ARDEC South. First-year data suggests that cultivar selection, rather than cluster pruning treatments, is a more important factor when considering total and marketable fruit yield and indicators of quality.Item Open Access Comparing natural area herbicides for residual weed control and native species tolerance(Colorado State University. Libraries, 2017) Clark, Shannon, author; Sebastian, Derek, author; Nissen, Scott, author; Sebastian, Jim, authorDowny brome (Bromus tectorum L.) is a competitive winter annual grass species, and is considered one of the most problematic invasive species on rangeland, open spaces and natural areas, and sites impacted by fire. Downy brome seeds germinate in the late summer or fall, overwintering until the seedlings begin rapidly growing in the spring, exploiting available water and nutrients before native grasses and forbs have emerged from dormancy. Invasive winter annual grasses, including downy brome, pose a major threat to native ecosystems by increasing fire frequency and intensity, degrading available wildlife and pollinator habitat, and decreasing native species diversity. Dalmatian toadflax (Linaria dalmatica L.) is another problematic invasive weed species found in dense populations in the western US, many times co-occurring with downy brome. Dalmatian toadflax infestations can be hard to control and the weed easily outcompetes native vegetation. The currently recommended herbicides (aminocyclopyrachlor, imazapic, picloram) for restoration of sites with invasive annual grasses and other biennial and perennial weeds have proven to provide inconsistent control or cause injury to desirable perennial species. Indaziflam, a new herbicide alternative for weed management in natural areas and open spaces, has been proven to provide long-term control of downy brome and other weed seedlings. A field trial was conducted to evaluate native species tolerance to indaziflam and other currently recommended herbicides used for downy brome and Dalmatian toadflax control. A total of 11 herbicide treatments were applied at two separate locations. For each native species, total counts were conducted across the entire plot area and analyzed as an increase or decrease compared to the non-treated control plots. Species richness was calculated by comparing the amount of unique species in each plot to the non-treated plots. Downy brome control, Dalmatian toadflax control, and perennial grass response were also evaluated through visual evaluations. Only indaziflam treatments (44, 73 and 102 g∙ai∙ha-1) increased native species richness (up to 8%, ± 1.2% SE) while providing 95-100% downy brome control. Imazapic treatments provided limited downy brome control and failed to increase species richness compared to non-treated plots. Aminocyclopyrachlor and picloram treatments resulted in a significant reduction in species richness, with up to a 35% decrease ± 1% SE compared to non-treated plots. Treatments containing picloram plus indaziflam provided significant control of Dalmatian toadflax compared to picloram alone, suggesting indaziflam provides extended control of the weed seedlings. These results suggest that indaziflam could be used by land managers as an alternative herbicide treatment, with less impact to native species, in restoring open spaces and natural areas severely impacted by downy brome and other invasive weed species. Additional work on the impact of herbicides to native species is needed to determine management options for restoration of native habitats. Future work includes conducting tolerance studies at sites where native species are grown in a production setting to reduce variability in species occurrence. Additionally, research looking at the impact of other weed management options, such as burning, to the native plant community is necessary for determining best management practices for restoration.Item Open Access The picornaviral polymerase fingers domain controls RNA binding and translocation(Colorado State University. Libraries, 2017) Watkins, Colleen L., author; Peersen, Olve B., authorThe picornavirus family of viruses includes poliovirus, the causative agent of paralytic polio and coxsackievirus, which is responsible for viral-heart-disease. Picornaviruses contain a single-stranded positive-sense RNA genome replicated by 3Dpol, an RNA-dependent RNA polymerase (RdRP). Crystal structures of 3Dpol from multiple picornaviruses have shown a conserved polymerase fold analogous to a “right hand” composed of fingers, palm and thumb domains. These crystal structures also identified unique regions in the fingers domain whose function in 3Dpol were unknown. Through biochemical kinetic analysis we have now determined the purpose of these regions, and their effects on the catalytic cycle of 3Dpol.Item Open Access Implementation of case studies in the undergraduate cadaveric classroom(Colorado State University. Libraries, 2017) Heise, Natascha, author; Kunkel, Megan J., author; Clapp, Tod R., authorLearning and studying human anatomy is often associated with using rote knowledge. Novice students often memorize terms and structures in the laboratory with little reasoning skills. In attempt to promote application, integration, and critical thinking skills we introduced case based study into the human anatomy course at CSU. Early implementation suggested little change in student’s ability to solve novel problems using simple recall in attempt to answer case study questions. Here, we describe a novel approach using a 5-step method to promote critical thinking. Results suggest students application and integration during the case studies correlated with overall class performance.Item Open Access Match me if you can! Plant-insect interactions in common cow parsnip Heracleum maximum (Apiaceae)(Colorado State University. Libraries, 2017) Smith, Brittany N., author; Leipzig-Scott, Peter, author; Ode, Paul, authorAnthropogenic climate change is altering the ecology of habitats and the life histories of species that live within it. Not only does climate change influence phenologies and geographic ranges of individual species, but variation in temperature and precipitation can affect how and when species interact. Ecological interactions between plants and their insects, pollinators and herbivores, are affected by abiotic and biotic factors, such as; temperature, allelochemicals, and herbivory. In our study, cow parsnip Heracleum maximum Bartram (Apiaceae), in a changing elevation gradient, may experience fitness differences if its phenology is matched or mismatched with its pollinators and/or herbivores.Item Open Access Cinnamon teal: a case of adaptive nest site selection(Colorado State University. Libraries, 2017) Setash, Casey, author; Kendall, William, author; Olson, Dave, authorItem Open Access Fine-scale genetic structure analysis of Bos taurus and Bos indicus adaptability(Colorado State University. Libraries, 2017) Krehbiel, B. C., author; Thomas, M. G., author; Hay, E. H., author; Blackburn, H. D., authorEnvironmental impacts have varying effects on animal agriculture and genetic adaptability is necessary for livestock to continue production in adverse conditions. Genetic diversity within a population enables genetic adaptability for livestock to withstand issues that may be altering production. Previous research revealed that genetic structure exists among Hereford cattle sampled from climate zones within the U.S. The cattle genetic structure was identified in allele frequencies of SNP that were associated with traits responsive to climate. Results revealed partitioning of the breed based on cool, warm, humid, and dry climates. Subsequently, the objective of this research was to use similar methods to identify genetic structure in seven cattle breeds (Hereford, Angus, Salers, Braford, Brahman, Simmental, and Nelore) in relation to SNP within genes associated with high altitude disease. Three-hundred and eight-eight cattle were genotyped using the BovineHD BeadChip (777,962 SNP). Seven genes were identified in literature that had been associated with high altitude disease in humans, poultry, swine, sheep, and cattle. Subsequently, SNP within the seven genes were queried from NCBI dbSNP database. Four hundred and fifty-one SNP located within high altitude genes were located on the BovineHD BeadChip. Twenty-seven SNP were removed due to low call rate on the animals. Genetic structure using the 424 SNP and principle component analysis was performed. The cattle were partitioned based on indicine or taurine descent. Also, breeds were partitioned based on high altitude structure. A separate SNP validation panel was used to determine whether differences observed in breeds was due to breed differences or high altitude structure. One-hundred SNP were randomly selected from the BovineHD BeadChip. Principle component analysis was performed and revealed partitioning between taurine and indicine cattle. However, the cattle genotypes partitioned differently compared to previous principle component analysis on the 424 SNP associated with high altitude disease. Preliminary analysis showed that genetic structure exists among the seven cattle breeds due to high altitude impacts. Therefore, cattle breeders can utilize this information to select cattle tolerant of high altitudes.Item Open Access Boot Camp Translation for the prevention of type 2 diabetes (T2D) in Fort Collins Hispanic/Latino adolescents(Colorado State University. Libraries, 2017) Annameier, Shelly, author; Schwartz, Laura, author; Haemer, Matthew, author; Shomaker, Lauren, author~50% of Hispanic/Latinos in the US will develop type 2 diabetes (T2D). Adolescent-onset T2D has an aggressive disease course, earlier mortality, and is a growing health concern. Standard lifestyle interventions have poor adherence and sustainability in adolescents at-risk for T2D. Psychosocial stressors and depressive symptoms may pose additional challenges for making lifestyle changes. There is a critical need for new approaches to preventing T2D in adolescents. Through a community-based participatory research program, "Boot Camp Translation," we examined evidence-based programs and cultivated culturally-tailored ideas for more effective prevention efforts, including launching focus groups to gather feedback for a comparative effectiveness trial.Item Open Access Improving soil health using tillage techniques to increase soil carbon sequestration(Colorado State University. Libraries, 2017) Leichty, Sarah, author; Cotrufo, Francesca, author; Stewart, Catherine, authorSoil carbon sequestration is a strategy to mitigate greenhouse gas emissions while enhancing microbial processes and water retention. Agricultural practices that leave residue on the surface without tilling have been promoted to sequester more C. However, recent work shows a redistribution of C rather than an increase when the entire soil profile is measured. This project will determine if surface application or incorporation (10 cm) stabilizes more residue throughout the soil profile (100 cm) using carbon stable isotope-labeled residue in a sprinkler-irrigated corn system in Colorado.Item Open Access Who influences whom in international politics?(Colorado State University. Libraries, 2017) Marrs, Frank W., authorState decisions in environmental policy are driven by international factors, but systematic assessment of this influence has proven elusive. For the first time, we examine the latent influence network that underlies global politics. We propose a model for longitudinal bipartite relational data to infer latent influence networks. Our approach provides improved interpretability and estimability over existing models while performing at least as well. We analyze a newly compiled dataset and find that strong positive and negative influences among countries and treaties do exist. These findings provide a means to understand the evolution of international environmental protection.Item Open Access Linking Pacific storms to North American heat waves(Colorado State University. Libraries, 2017) Jenney, Andrea, author; Randall, David A., authorLong-range predictions of heat waves offer little improvement over climatology despite the continuing improvements of weather forecast models. Tropical variability in weather at sub-seasonal timescales is well-understood to influence weather in the Extratropics, particularly in the winter. For this reason, it is considered a potential source of sub-seasonal predictability of weather. However, much less is understood about the tropical-extratropical connection in the summer. we show that a major climate oscillation in the tropical west pacific is significantly correlated to U.S. heat waves with long lead times, suggesting potential for use in seasonal prediction of these events.Item Open Access What is said is more important than who says it: an experimental study of content and prestige biases in social learning(Colorado State University. Libraries, 2017) Berl, Richard E. W., author; Samarasinghe, Alarna N., author; Roberts, Sean G., author; Gavin, Michael C., author; Jordan, Fiona M., author; Gray, Russell D., authorEvery human on our planet belongs to a culture, and we all begin to learn this information very early in life. But to accomplish this, we each have some very important decisions to make: What do we learn and who do we learn it from? And what do we do when these signals compete for our attention? To answer this, we used speakers of high and low prestige and two artificially constructed creation stories to test what information people use. Our findings may upturn our understanding of how humans learn and behave, and how our extraordinary capacity for culture evolved.Item Open Access A framework for seismic resilience and recovery of hospital clusters(Colorado State University. Libraries, 2017) Hassan, Emad, author; Mahmoud, Hussam, advisorUnderstanding the behavior of hospitals is essential specially after major earthquakes. A comprehensive framework is presented to estimate losses of hospital clusters, quantity and quality functionality and recovery. The framework includes the recovery of different lifelines and is applied to Shelby County as a testbed to investigate the effect of interdependence on functionality and recovery assessment as well as the mutual effect of the hospitals. A patient-driven model is introduced to estimate the demand on each hospital, which affects the quality of the hospitalization service. This framework can be utilized by emergency planners for pre- and post-disaster recovery management.Item Open Access Fluorescent labeling of extracellular markers on stem cells from human breast milk(Colorado State University. Libraries, 2017) Carranza, Kasimir, author; Allen, Christopher P., author; Henao-Tamayo, Marcela, author; Hanneman, William, authorPumping breast milk and freezing it is common practice in hospitals, neonatal intensive care units (NICU), and numerous households. Freezing milk may alter the cellular constituency of breast milk by reducing the amount of stem cells. Here, we investigate the alteration of stem cell viability and concentration in human breast milk frozen at varying temperatures and durations. This reduction may negatively impact infant development; vulnerable populations such as preterm infants have higher nutritional requirements and less volumetric capacity in their stomach. Freezing milk may undermine attempts to supply preterm infants with the nutritional requirements needed to sustain life.Item Open Access 3D-printed microfluidic device for the analysis of intestinal tissue ex vivo(Colorado State University. Libraries, 2017) McLean, Ian, author; Schwerdtfeger, Luke, author; Wilson, Jessie, author; Henry, Charles, author; Tobet, Stuart, authorCurrently, most in vitro experimental models of the intestine rely upon cell lines, and consequently, lack the diverse representation of cells present in vivo. Slices of intestine, removed from living organisms, offer a better representation of in vivo physiology. However, current techniques for maintaining intestinal tissue in vitro are not capable of recapitulating the in vivo environment. This project utilizes 3D printing and microfluidic principles to design a device that delivers differential flows of media across the two surfaces of intestinal tissue. The device will enable the investigation of complex biological questions that previous models have been unable to address.Item Open Access Protein interaction with glycocalyx-mimetic surfaces: a candidate for blood-compatible materials(Colorado State University. Libraries, 2017) Hedayati, Mohammadhasan, author; Krapf, Diego, author; Kipper, Matt J., authorBiomaterials and medical devices induce tissue responses when they get into contact with human blood and rapidly becomes covered with a layer of nonspecifically adsorbed proteins. For blood contacting devices, protein adsorption is undesirable and is generally the first event in blood coagulation. The polymer coating on solid surfaces is an efficient approach for modification of materials to design protein resistant biomaterials. The aim of this work is to mimic the endothelial glycocalyx layer on the surface of blood vessels, which is responsible for anticoagulant activity by restricting molecules such as proteins from reaching the endothelium.Item Open Access A portable biosensor system for pathogen diagnostic applications(Colorado State University. Libraries, 2017) Yang, Lang, author; Filer, Jessie, author; Chen, Tom, authorThe platform uses the electrochemical impedance spectroscopy (EIS) technique for pathogen detections. It includes sensor front end, stimulus generation, analog sensor data acquisition and conditioning, digital-to-analog conversion, back-end digital signal processing, wireless interface and a user phone app. The platform is powered by a USB based rechargeable battery at 3.3V. At a area cost of 28cm2. An average error of 2.6% is achieved compared to commercial counterpart.Item Open Access Assessing the efficacy of treatments for digital dermatitis in organic dairy systems(Colorado State University. Libraries, 2017) Paudyal, Sushil, author; Pinedo, Pablo, authorDigital dermatitis is a major cause of lameness in dairy cows causing pain in the limbs leading to reduced animal welfare and significant economic loss. With strict antibiotic regulations and increasing organic dairies, the clinically validated non-antibiotic treatment options are of great value. The objective of the study was to evaluate the efficacy of treatment of digital dermatitis using different combinations of copper sulfate, iodine, and honey. Cows with M1 and M2 DD lesion score were identified and enrolled in the hoof-trimming chute. Cows were randomized to be treated with one of the three treatment options: Copper sulfate and Iodine (CS-I), Honey and Iodine (HO-I) and Control (CON). All 70 cows were followed up on D3, D12 and D28 and a subsample of 45 cows were followed until d120 to evaluate lesion size, lesion stage, lameness score and pain response. Tissue samples were collected on D3, D28 and D120 to investigate dynamics of microbial metagenomics. The data were analyzed in SAS using PROC MIXED and PROC GENMOD with repeated measures. The results show that 43% of the lesions were found on the left feet and 57% on the right feet. The early erosive form of lesions changes into papillomatous mature form as the lesion progresses irrespective of treatment application. The lesion size differed among treatment groups and the effect varied with different follow-up days (P< 0.05). The lesion decreased for both CS-I and HO-I group till day 12 after which the HO-I group had an increase in lesion size. In contrast to this CON group had a slower decrease in lesion size. The pain response was decreased for CS-I and less for HO-I groups. The odds of pain and the odds of getting a lame cow decreases as the time progresses. Thus, non-antibiotic treatment options are effective in controlling pain and decreasing lesion size up to 12 days. Also, clinical assessment of animals and evaluation of lesions suggest CS-I combination is superior to HO-I and CON group.Item Open Access Sailing(Colorado State University. Libraries, 2017) LaCrosse, Michelle, authorThis essay examines the narrator's desire to travel and explore, what that means to her family life, and how she feels about it through personal experiences with sailing, growing up in the Pacific Northwest and learning about the lives and journeys of early global explorers.Item Open Access Evaluating the relationship between physical activity, gross motor skills and healthy growth in preschoolers using structural equation modeling(Colorado State University. Libraries, 2017) Courtney, Jimikaye B, author; Grimm, Kevin, author; Boles, Richard E, author; Johnson, Susan L, author; Bellows, Laura L, authorPurpose: The purpose of this study was to use structural equation modeling (SEM) to understand the directionality of the relationship between physical activity (PA) and gross motor skills (GMS) in predicting healthy growth (body mass index, (BMI)) in preschoolers. Procedure: Baseline data from preschoolers (4-5 years old) enrolled in the Colorado Longitudinal Eating And Physical activity (LEAP) study were used. Preschoolers were assessed on GMS (balance, locomotor and ball skills) and fitness (Bruininks-Oseretsky Test of Motor Proficiency, Second Edition), PA (Actical accelerometers), and perceived physical competence (The Pictorial Scale of Perceived Competence and Social Acceptance for Young Children, (PPC)). Measured height and weight were used to calculate preschoolers’ BMI. SEM was performed using Mplus software to test two models. Both models used the same combination of manifest variables to define six latent variables: three GMS-balance skills, locomotor skills, ball skills, PA, PPC, and fitness. Model 1 tested PA predicting the three GMS (balance, locomotor, and ball skills) and GMS predicting BMI. Model 2 tested the three GMS predicting PA and PA predicting BMI. Paths for PPC and fitness were tested in both models. All latent variables and BMI were regressed on preschooler ethnicity, age, and sex. Model fit was assessed using Chi-square and root mean square error of approximation (RMSEA), with p >.05 and p <.05 as indicators of close fit, respectively. Results: Model 1, testing PA predicting the three GMS (balance, locomotor, and ball skills) and GMS predicting BMI, demonstrated acceptable fit (Chi-square(556)=805, p>.05; RMSEA=.044). PA significantly, positively predicted locomotor and ball skills. Locomotor skills significantly, positively predicted fitness. Fitness did not significantly predict BMI; however, the relationship was in the expected direction (b=-0.176, p=.09). Model 2, testing three GMS predicting PA and PA predicting BMI, demonstrated acceptable fit (Chi-square(558)=824, p>.05; RMSEA=.045). Locomotor skills significantly, positively predicted PA. PA significantly, positively predicted fitness. Fitness did not significantly predict BMI; however, the relationship was in the expected direction (b=-0.132, p=.18). Implications/Future Directions: Both models showed significant pathways from locomotor skills to PA, and vice-versa, suggesting the need for additional research to examine the potential for reciprocity between PA and locomotor skills. Ball skills were not predictive of PA, likely due to preschoolers’ relatively low ball skill proficiency. Additional analyses will test individual latent variables in each model as mediators and will test direct paths from physical activity to fitness (model 1) and from physical activity to BMI (both models). Additional research is required to determine whether fitness or PA is a more appropriate predictor of health risk (BMI) in preschoolers. Longitudinal data are necessary to determine how the directionality of these relationships changes throughout child development, a next step for the Colorado LEAP study data set.