Northern Colorado Research Articles

The beta-adrenergic agonist zilpaterol hydrochloride may predispose feedlot cattle to cardiac remodeling and dysfunction

Background: The aim of this study was to address producer concerns that the β2-adrenergic agonist zilpaterol hydrochloride, a bovine growth promotant, predisposes cattle to cardiac disease and death. Our objectives were to evaluate the effect of zilpaterol on cardiac function, morphology, and risk of myocardial injury. Methods: A prospective, case-control study was conducted on one feedlot in northern Colorado using convenience sampling of Angus-based steers (n = 80). Pulmonary arterial pressures (mean, systolic, and diastolic) were measured. Plasma cardiac troponin I was measured in a sub-sample of steers that were followed to slaughter (n = 31). The carcass, left ventricle plus inter-ventricular septum, and right ventricle were weighed. Results: Relative to controls, steers fed zilpaterol hydrochloride had an adjusted left ventricle and septum that was 185 g heavier (95 % CI: 19, 350 g; P = 0.03), a diastolic pulmonary arterial pressure that was 10 mm Hg greater (95 % CI: 3, 17 mm Hg; P = 0.004), and a greater concentration of cardiac troponin I (P = 0.01), a biomarker of myocardial injury. Furthermore, left ventricular mass tended to be positively and deleteriously associated with diastolic pulmonary arterial pressure in steers fed zilpaterol (P = 0.08) but not controls (P = 0.28). Conclusions: Our findings suggest that zilpaterol hydrochloride induced sufficient left ventricular hypertrophy to cause impaired left ventricular relaxation or diastolic dysfunction and myocardial injury. In conclusion, these results support concerns that, in the feedlot studied, zilpaterol hydrochloride predisposes cattle to cardiac disease.

EVIDENCE OF TWO COCIRCULATING CANINE DISTEMPER VIRUS STRAINS IN MESOCARNIVORES FROM NORTHERN COLORADO, USA.

Canine distemper virus (CDV) is a highly contagious pathogen that principally infects wildlife and domestic carnivores. Peridomestic species such as raccoons ( Procyon lotor) experience outbreaks with high mortality. Clinical signs of infection include anorexia, fever, respiratory infection, and neurologic complications. Although not zoonotic, CDV poses a high risk to unvaccinated domestic animals and the conservation of endangered species. During 2013-16, we opportunistically collected wild and domestic carnivore specimens through a rabies surveillance program in northern Colorado, US. Brainstem and cerebellar tissue samples were independently tested for rabies and CDV by fluorescent antibody test. We tested a total of 478 animals for CDV, comprised of 10 wild and domestic carnivore species. A total of 15% (72/478) of all animals sampled tested positive for CDV, consisting of 24% (71/300) of raccoons and 4% (1/26) of coyotes ( Canis latrans), but coinfection with rabies virus was not observed among CDV-positive animals. We extracted RNA from positive tissues, and a reverse-transcription PCR was used to create complementary DNA. We amplified and sequenced the hemagglutinin gene from 60 CDV-positive tissues, and a median joining network and maximum likelihood phylogenetic tree revealed two major lineages among samples. Phylogenetic analysis indicated that our sequences were most similar to the America-2 ( n=55) and the America-3 ( n=5) CDV lineages circulating in North America. Our results indicated two distinct and distantly related clades of CDV overlapping geographically and temporally among raccoon populations in northern Colorado.

The Tigriopus CURE - A Course-Based Undergraduate Research Experience with Concomitant Supplemental Instruction.

Evidence indicates that students who participate in scientific research during their undergraduate experience are more likely to pursue careers in the STEM disciplines and to develop increased scientific reasoning and literacy skills. One avenue to increase student engagement in research is via their enrollment in course-based undergraduate research experiences (CUREs), where they are able to conduct authentic research as part of the laboratory curriculum. The information presented herein provides an example of a CURE which was developed and implemented in an introductory cell and molecular biology course at the University of Northern Colorado. In addition to describing the Tigriopus CURE curriculum itself, we also present evidence regarding the effectiveness of the CURE in promoting students’ development of confidence in science process skills, quantitative reasoning skills, and written communication skills. The curricular details of the Tigriopus CURE are provided in this article to provide instructors who are interested in CUREs the opportunity to implement this specific CURE in their own course.

The Spatial and Temporal Variability of Meltwater Flow Paths: Insights From a Grid of Over 100 Snow Lysimeters

AbstractSnowmelt is an important part of the hydrologic cycle and ecosystem dynamics for headwater systems. However, the physical process of water flow through snow is a poorly understood aspect of snow hydrology as meltwater flow paths tend to be highly complex. Meltwater flow paths diverge and converge as percolating meltwater reaches stratigraphic layer interfaces creating high spatial variability. Additionally, a snowpack is temporally heterogeneous due to rapid localized metamorphism that occurs during melt. This study uses a snowmelt lysimeter array at tree line in the Niwot Ridge study area of northern Colorado. The array is designed to address the issue of spatial and temporal variability of basal discharge at 105 locations over an area of 1,300 m2. Observed coefficients of variation ranged from 0 to almost 10 indicating more variability than previously observed, though this variability decreased throughout each melt season. Snowmelt basal discharge also significantly increases as snow depth decreases displaying a cluster pattern that peaks during weeks 3–5 of the snowmelt season. These results are explained by the flow of meltwater along snow layer interfaces. As the snowpack becomes less stratified through the melt season, the pattern transforms from preferential flow paths to uniform matrix flow. Correlation ranges of the observed basal discharge correspond to a mean representative elementary area of 100 m2, or a characteristic length of 10 m. Snowmelt models representing processes at scales less than this will need to explicitly incorporate the spatial variability of snowmelt discharge and meltwater flow paths through snow between model pixels.

Measuring Mountain River Discharge Using Seismographs Emplaced Within the Hyporheic Zone

AbstractFlow and sediment transport dynamics in fluvial systems play critical roles in shaping river morphology, in the design and use of riverine infrastructure, and in the broader management of watersheds. However, these properties are often difficult to measure comprehensively. Previous work has suggested the use of proximal seismic signals resulting from flow and bed load transport to construct more complete records of these fluvial processes. We investigate a small (184 km2; < 20 m3/s), snowmelt‐fed mountain river in the Northern Colorado Rocky Mountains during May–August 2015 to capture peak runoff with colocated measurements of discharge and seismic noise. Three‐component seismometers were placed in close proximity to the channel bank (~1 m) within the hyporheic zone (at times submerged beneath the water table). We recorded a broad spectrum of seismic signals excited by discharge, including novel, low‐frequency (0.1–2 Hz) signals observed predominantly on the horizontal components. The characteristics of these low‐frequency signals are not consistent with an elastically propagating seismic wave. We instead infer that they likely arise from the sensor tilting in response to viscoelastic deformation occurring near the channel and propose large‐scale turbulent eddies as a forcing mechanism. Calibrating horizontal seismic power with hydrograph flow rates over the course of a rainstorm for individual sensors, we demonstrate that these unique signals can be used to accurately estimate river discharge with simple regressions. This technique shows promise for augmenting seismic monitoring of rivers by enabling discharge rates to be estimated from outside the channel using easily deployed and noninvasive seismic instrumentation.

Acidic Cloud Episodes in the Northern Colorado Rockies: Inadvertent Weather Modification?

Acidic cloud episodes were detected in January 1998 and January 2000 at Storm Peak Laboratory (SPL) in the northern Colorado Rockies. The episodes were characterized by increased concentrations of small droplets and condensation nucleus concentrations and reduced liquid water contents, snowfall rates and sub-cloud relative humidities. The trajectories of the air parcels arriving at SPL before, during and after the episodes were studied. The parcels arriving during the episodes encountered the least precipitation during their journey to SPL, suggesting little cloud and precipitation scavenging of aerosol particles. Further, much of the difference in acidity can be explained by dilution of the cloud droplets. Thus, the episodes may be primarily a natural phenomenon.

Hydrologic flow path development varies by aspect during spring snowmelt in complex subalpine terrain

Abstract. In many mountainous regions around the world, snow and soil moisture are key components of the hydrologic cycle. Preferential flow paths of snowmelt water through snow have been known to occur for years with few studies observing the effect on soil moisture. In this study, statistical analysis of the topographical and hydrological controls on the spatiotemporal variability of snow water equivalent (SWE) and soil moisture during snowmelt was undertaken at a subalpine forested setting with north, south, and flat aspects as a seasonally persistent snowpack melts. We investigated if evidence of preferential flow paths in snow can be observed and the effect on soil moisture through measurements of snow water equivalent and near-surface soil moisture, observing how SWE and near-surface soil moisture vary on hillslopes relative to the toes of hillslopes and flat areas. We then compared snowmelt infiltration beyond the near-surface soil between flat and sloping terrain during the entire snowmelt season using soil moisture sensor profiles. This study was conducted during varying snowmelt seasons representing above-normal, relatively normal, and below-normal snow seasons in northern Colorado. Evidence is presented of preferential meltwater flow paths at the snow–soil interface on the north-facing slope causing increases in SWE downslope and less infiltration into the soil at 20 cm depth; less association is observed in the near-surface soil moisture (top 7 cm). We present a conceptualization of the meltwater flow paths that develop based on slope aspect and soil properties. The resulting flow paths are shown to divert at least 4 % of snowmelt laterally, accumulating along the length of the slope, to increase the snow water equivalent by as much as 170 % at the base of a north-facing hillslope. Results from this study show that snow acts as an extension of the vadose zone during spring snowmelt and future hydrologic investigations will benefit from studying the snow and soil together.

Molecular ecology of Listeria spp., Salmonella, Escherichia coli O157:H7 and non-O157 Shiga toxin-producing E.coli in pristine natural environments in Northern Colorado.

Molecular subtyping is commonly used in foodborne disease surveillance and microbial source tracking. There is a knowledge gap regarding the molecular ecology of foodborne pathogens in non-food-associated environments. The objective of this study was to isolate and subtype foodborne pathogens from pristine natural environments with minimal anthropogenic inputs. Five locations (wilderness areas) in Northern Colorado were sampled during the spring, summer and fall over a 2-year period. Soil, water, sediment, surface soil and wildlife faecal samples were microbiologically analysed to detect Listeria, Salmonella and Shiga toxin-producing Escherichia coli (STEC), and resultant isolates were subtyped. Three samples tested positive for Listeria monocytogenes and 19 samples contained other Listeria spp. Salmonella was isolated from two samples, five samples contained non-O157 STEC, and E.coli O157:H7 was not detected. Two L. monocytogenes isolates from faecal samples collected from the same wilderness area over a year apart shared the same PFGE pattern, while all other isolates had a unique type. Our data indicate that (i) there was a rare presence of human foodborne pathogens in pristine natural environments in Northern Colorado, (ii) there was genetic diversity between organisms isolated within a given wilderness area, and (iii) the Northern Colorado climate and topography may contribute to the low occurrence of these organisms. Relatively little is known about the molecular ecology of foodborne pathogens in pristine natural environments. While foodborne pathogens were rarely detected in wildlife faecal and environmental samples from the wilderness areas in this study, some isolates shared DNA fingerprint types with human clinical isolates from same region during the same time frame, highlighting the need for environmental isolate subtype data. The availability of molecular subtyping data for non-food-associated foodborne pathogen isolates can facilitate epidemiological and microbial source tracking investigations.

Analyzing root traits to characterize juniper expansion into rangelands

Juniper expansion into sagebrush-dominated communities is a phenomenon occurring across large regions of the western U.S. in the past century. We investigated the competitive abilities for belowground resources of Juniperus osteosperma (Utah juniper) and Artemisia tridentata (big sagebrush) based on fine root traits and spatial patterns of water uptake inferred from stem and soil stable oxygen isotopes (δ18O). Data were collected from neighboring J. osteosperma and A. tridentata plants in northern Colorado and included measurements of different size classes of J. osteosperma: short (<30 cm), intermediate (30 cm–3 m), and tall (>3 m). Short J. osteosperma switched from utilizing shallow to primarily deep water sources across the growing season. Artemisia tridentata had root traits associated with faster root proliferation and resource acquisition (significantly greater specific root length and smaller root diameter, p < .01), but greater J. osteosperma fine root biomass (p < .01) resulted in similar root length densities between the two species at most soil depths (p > .1). Additionally, we found that short J. osteosperma individuals can quickly develop deep root systems, but there is little difference in belowground foraging between individuals of J. osteosperma and A. tridentata based on the depth of water uptake and root length density.

Seasonality, sources and sinks of C1–C5 alkyl nitrates in the Colorado Front Range

We describe observations of C1–C5 alkyl nitrates made at the Boulder Atmospheric Observatory in Northern Colorado in winter 2011, spring 2015, and summer 2015. Average mixing ratios of the alkyl nitrates are similar across the seasons, but increased diel variability in summer suggests increased production balanced by increased loss relative to winter and spring. We use a sequential production-destruction model based on ratios of alkyl nitrates to their parent alkanes to investigate seasonal sources and sinks of C1–C5 alkyl nitrates. We explore the role of uncertainties in the production and loss kinetic parameters on the interpretation of local atmospheric photochemical aging through the use of a photochemical clock based on the evolution of the ratios of alkyl nitrates to their parent alkanes over time. Photochemical age is typically consistent with hours from sunrise, suggesting that the site experiences well-mixed air masses dominated by daily photochemistry with little carry-over from the previous day or from other locations. Contrary to studies in other locations, we obtain good model-measurement agreement using a newer upper-bound ethyl nitrate branching ratios. This suggests that the efficiency of ethyl nitrate production from ethane oxidation has previously been underestimated, and decreases the relative importance of alkoxy radical decomposition versus ethane photochemistry on ethyl nitrate production. We estimate the dry deposition velocity of methyl nitrates is small and consistent with previous estimates, and that deposition velocities increase with carbon number for the C2–C5 RONO2. Dry deposition is a small daytime sink relative to photolysis and reaction with OH for the alkyl nitrates, but improves the model-measurement comparison for methyl nitrate.

UAS-based remote sensing applications on the Northern Colorado Limited Irrigation Research Farm

USDA-ARS (Agricultural Research Service) Water Management and Systems Research Unit established a Limited Irrigation Research Farm (LIRF) inNorthern Colorado in 2008 to respond the urgent need of sustaining irrigated agriculture in semi-area regions with limited water resources and increasing population. Agricultural research has been conducted at this facility to optimize irrigation strategy, accurately quantify crop water use, develop sensor-based irrigation scheduling algorithms, and investigate physiological responses to crop water stress. An unmanned aerial system (UAS) was developed and used to collect multispectral and thermal imagery for irrigation and other field applications. The results in the study confirmed the capability of UAS to collect high-quality, high spatial and temporal resolution crop data for field-based agricultural applications and aid farmers to manage their water resources and sustain crop production in a more advanced way. Keywords: NDVI, CRSI, CWSI, maize, water stress, genotype, yield DOI:  10.33440/j.ijpaa.20190202.50.  Citation: Zhang H, Yemoto K. UAS-based remote sensing applications on the Northern Colorado Limited Irrigation Research Farm.  Int J Precis Agric Aviat, 2019; 2(2): 1–10.

Nothing Like a Love Sonnet for Greeley, Colorado, &lt;em&gt;or&lt;/em&gt; Something Like a Love Poem for Greeley Queers, 1993–1998 / For Angie Zapata

In a Different Voice, and: Nothing Like a Love Sonnet for Greeley, Colorado, or Something Like a Love Poem for Greeley Queers, 1993–1998, and: For Angie Zapata Qwo-Li Driskill (bio) Keyword Colorado, poetry, queer, transgender, violence My poetry is rooted in the poetic traditions of queer women of color feminists who argue for poetry as a tool for radical social transformations. Audre Lorde, in her pivotal essay "Poetry Is Not a Luxury," asserts that "Poetry is the way we help give name to the nameless so it can be thought. The farthest external horizons of our hopes and fears are cobbled by our poems, carved from the rock experiences of our daily lives."1 Poetry is theory, and I'm also in agreement with AIDS activist and artist Avram Finkelstein when he writes that "art that isn't about communication is about class."2 Poetry is a tool to communicate, to theorize, to bear witness, and to imagine both the past and the future. Queer and trans people, particularly queer and trans people of color, continue to endure horrific violence and—it seems quite clear to me—both ongoing violence and a backlash against our movements. There were twenty-six known murders of trans people in the United States—almost all of them black trans women—in 2017. The current presidential administration and their vociferous followers are horrific to me not because of a sense of shock caused by their actions but because of a sense of deep familiarity. I already know this story—it's the once-againness of the American nightmare that is traumatizing. While I don't wish to guide an interpretation of my poetry, I will say that both of these poems are rooted in a particular place and context. I was an undergraduate student in Greeley at the University of Northern Colorado from 1993–98. At the time, it was an extremely dangerous place for me as a queer/trans person. My experiences in Greeley were not mine alone—there was a [End Page 93] small, very fierce, group of queer and trans youth activists who created deep connections with each other during that time. We were constantly under attack. And we survived. We were lucky. In 2008, Angie Zapata was a young trans Latinx woman beaten to death in Greeley. Zapata's murder was the first anti-trans murder to be considered a hate crime under US law. While Angie's murder happened a decade after I left Greeley, and I did not know her, Angie's story haunts me. Poetry is a way of telling myself the stories I need to hear. Sometimes, those stories are simply a naming of emotional, material, and political realities that those in power want to obliterate. These poems are part of what Gloria Anzaldúa and Cherríe Moraga call a "theory in the flesh" in which "the physical realities of our lives—our skin color, the land or concrete we grew up on, our sexual longings—all fuse to create a politic born out of necessity."3 Moraga, in her introduction to the new edition of This Bridge Called My Back revisits the concept of "theory in the flesh": "The body—that site which houses the intuitive, the unspoken, the viscera of our being—this is the revolutionary promise of 'theory in the flesh' for it is both the expression of evolving political consciousness and the creator of consciousness, itself. Seldom recorded and hardly honored, our theory incarnate provides the most reliable roadmap to liberation."4 I hope the two poems I offer here can contribute to that roadmap through the naming of violences and their aftermaths as we collectively work together for our liberated futures. [End Page 94] Nothing Like a Love Sonnet for Greeley, Colorado, or Something Like a Love Poem for Greeley Queers, 1993–1998 When I escaped, I smuggled the color of lilacs—the only sweet fragrance for miles—and the bruised and brutalwork as we hunkered down for the next attack.We honed an insurgent mercy, dislodged gravelfrom mangled heartbreak with our love gnarlingdeep in my stomach. I can't forget the stenchof methane. Maybe...

Al Sur del Sur South by Southwest

Al Sur del Sur South by Southwest Fotos de Tony Canossa1 Click for larger view View full resolution 1. Unleashing the dragon—Liberando el dragón [End Page 183] Click for larger view View full resolution 2. The lost kingdom—El reino perdido [End Page 184] Click for larger view View full resolution 3. Monday morning—A trabajar [End Page 185] Click for larger view View full resolution 4. Waiting for it—Esperándola [End Page 186] Click for larger view View full resolution 5. Hunted hunter—Cazador cazado [End Page 187] Click for larger view View full resolution 6. Looping huaso—Lazada [End Page 188] Click for larger view View full resolution 7. Catwheel sunset—Dando vueltas de gato [End Page 189] Click for larger view View full resolution 8. Riding the dragon—Cabalgando el dragón [End Page 190] Footnotes 1. Born in El Salvador, son and brother of photographers, photography has been many things for him since early childhood: An ever present love, a way to share with others the richness of life by holding still, for a moment, a spark of it's never ending flow, and a humble way of showing gratitude and appreciation for the privilege of seeing. Copyright © 2018 Board of Trustees of the University of Northern Colorado

Changes in summertime ozone in Colorado during 2000–2015

In 2016, the Denver Metro Area (DMA)/Northern Colorado Front Range (NCFR) was reclassified from a Marginal to a Moderate O3 Non-Attainment Area due to the prevalence of high summer ozone (O3) occurrences. Hourly surface O3 data collected during 2000–2015 from a total of 80 monitoring sites in the State of Colorado were investigated for geographical features in O3 behavior and O3 changes over time. We particularly focus on summer O3 (June, July, August), which is the time when most exceedances of the O3 National Ambient Air Quality Standard (NAAQS) have been recorded. Variables investigated include the statistical (5th, 50th (median), and 95th percentile) distribution of O3 mixing ratios, diurnal amplitudes, and their trends. Trend analyses were conducted for 20 site records that had at least ten years of data. The majority of Colorado ozone monitoring sites show an increase of the 5th (16 total; 11 of these are statistically significant (p-value ≤ 0.05) trends) and 50th (15 total; 4 statistically significant trends) percentile values. Changes for the 95th percentile values were smaller and less consistent. One site showed a statistically significant declining trend, and one site an increasing trend; the majority of other sites had slightly negative, albeit not statistically significant declining O3. Ozone changes at the two highest elevations sites (&amp;gt;2500 m asl) are all negative, contrasting increasing O3 at U.S. West Coast sites. NCFR urban sites do not show the rate of decreasing higher percentile O3 as seen for the majority of urban areas across the U.S. during the past 1–2 decades. The amplitudes of diurnal O3 cycles were studied as a proxy for nitrogen oxides (NOx) emissions and the diurnal O3 production chemistry. The majority of sites show a decrease in the median summer O3 diurnal amplitude (19 total/10 statistically significant). This is mostly driven by the increase in nighttime O3 minima, which is most likely a sign for a declining rate of nighttime O3 loss from titration with nitric oxide (NO), indicating a change in O3 behavior from declining NOx emissions. Since median and upper percentile surface O3 values in the DMA have not declined at the rates seen in other western U.S. regions, thus far the reduction in NOx has had a more pronounced effect on the lower percentile O3 distribution than on high O3 occurrences that primarily determine air quality. An assessment of the influence of oil and gas emissions on Colorado, and in particular DMA O3, is hampered by the sparsity of monitoring within oil and gas basins. Continuous, long-term, high quality, and co-located O3, NOx, and VOC monitoring are recommended for elucidating the geographical heterogeneity of O3 precursors, their changing emissions, and for evaluation of the effectiveness of O3 air quality regulations.

High Altitude Makes for High Energy

On January 19, 2018 about 80 people sat in an unassuming conference room on the campus of the University of Northern Colorado in Greeley, chatting and signing away cheerfully with their seat neighbors in anticipation of the keynote address by Susanne Even from Indiana University in Bloomington, IN. The lively crowd of students and faculty members from across the country was clearly already in a chatty mood before the official introduction by Erin Noelliste, the lead organizer of the 5th Scenario Symposium on Performative Pedagogy, kicked off an engaging and interactive evening and day ahead. The idea behind this particular symposium was to focus on the use of drama to enhance learning in education and foreign languages, as the program stated. It was the second of its kind held in the US and thus aimed at broadening readership and scope of the Scenario Journal, with the goal of inspiring creativity and improvisation in foreign language classrooms. The keynote speaker Susanne Even took the podium and I dare say she could not have hoped for a more involved group of lifelong learners. Her keynote talk, made accessible to all participants by sign language interpreters, was the first presentation in the 2018 ...

Recent Developments in Gateway Phase Research

The Gateway tradition was defined by Alan D. Reed in 1997 to describe a class of prehistoric sites in west-central Colorado that had previously only been described in generic terms or as a local variant of well-known cultural traditions such as Ancestral Puebloan or Fremont. Reed and Michael D. Metcalf elaborated upon the new archaeological taxon in the prehistoric context for the Northern Colorado River basin, which was published in 1999. Several studies and research projects conducted since that time have resulted in new datasets that are relevant to many of the research questions and data gaps identified by Reed and Metcalf for the Gateway tradition. A consideration of these data has resulted in new insights into the lifeways of these people and a taxonomic reformulation of the Gateway tradition into the Gateway phase.

Contrasting behavior of slow and fast photoreactive gases during the August 21, 2017, solar eclipse

The total solar eclipse on August 21, 2017, provided a rare opportunity to observe and test our understanding of atmospheric dynamics and photochemical dependency on solar irradiance. Here, we utilize observations from the continuous monitoring of both slow and fast photochemically reacting trace gases near Boulder, Colorado, for evaluating the unique dynamic and photochemical forcings on the eclipse day. The monitoring station saw a 93% solar obstruction during the peak of the eclipse. Eclipse day data are contrasted with the full month’s record from this site. The loss of irradiance caused cooling of the surface air by ~3°C, and weakened convective and turbulent mixing. This resulted in a buildup of slow photoreactive gases (methane, short-chain non-methane hydrocarbons), as well as total nitrogen oxides (the sum of nitric oxide (NO) + nitrogen dioxide (NO2)) in the surface layer. In contrast, ozone (O3) declined by ~15 ppb during the first phase of the eclipse compared to median August diurnal mixing ratios. Similar O3 signatures were observed at a series of network stations along the Northern Colorado Front Range. With the loss of irradiance, the initial ratio of NO/(NO + NO2) of ~0.2 dropped steadily, bottoming out at &amp;lt;0.01, but rebounded to approximately two times above August median levels for this time of day towards the end of the eclipse. Above average O3 enhancements were seen in the afternoon hours following the eclipse at this and a series of other nearby surface O3 monitoring sites. The contrasting behavior of these slow and fast photoreactive gases, and comparison with other published eclipse data, allow characterizing these responses as more typical for an urban/polluted environment.

Letters, Beers, and The Great Spanish Novel

Letters, Beers, and The Great Spanish Novel Linda González Baena, Julio. Tosilos. Madrid: Huerga y Fierro Editores, 2015. 235 pp. ISBN 978-84-943805-3-2. Tosilos is the first published work in prose fiction that follows several other books by Julio Baena. In his afterword, the author describes his work as “barely a minor pseudo-sequel to the Great Spanish Novel”. The Spanish novel he refers to here is Don Quixote by Miguel de Cervantes. In Tosilos, the reader experiences firsthand narrations from Don Quixote’s character named Tosilos, the lackey who is ordered to fight Don Quixote. In addition, the author includes fictional narratives from the perspective of a bartender in a bar in the United States as well as from a group of foreign students, most likely from Spain, as he opens with a letter to a nun that the author includes as he initiates the story. The reader is a witness to Tosilos’ journey through life as he ponders his agency. The author uses the meaning of the lackey’s name along with his actions and decisions in life to map out this journey. Tosilos offers an alternative in-depth view of several characters found in Don Quixote. The narrative utilizes the fictional research findings of both an older character and a foreign group of students who attempt to discover and unravel Tosilos’ history. As the narrative progresses, the two are unaware of their common interests for Tosilos, even though they can frequently be found at the same bar. The bartender also offers her perspective of the two in what becomes an impression of self-realization for all involved. Julio Baena oscillates between contemporary and past events and weaves various genres such as poetry and epistolary into his prose in order to fuse the various events and characters. The story unravels the fictional circumstances that led Tosilos to his encounter with Don Quixote and Sancho Panza. Tosilos gives the reader a glance at what life was like for the lackey prior to this encounter and thereafter. It is through this chain of events that Tosilos discovers he can be anyone or anything as described in the book: Recordaba que le gustaba que lo enviasen de correo. Que estando solo, y quitada la gorra, y vuelto el jubón del revés, se descargaba de su peso diario, de ser y parecer lacayo en cada cosa que hiciera. Solo, de camino, si entraba a refrescarse al pozo de cualquier corral, no era lacayo de nadie. Ni siquiera [End Page 151] era Tosilos. Era, en cada encuentro, como un comienzo de existencia. Podían preguntarle quién era, e incluso de quién servía—, pero él podía callar, o mentir, o informar, y partir de ahí con quien fuese. Sólo tenía que disfrazar su ropa de lacayo. (131) The use of clothing, whether it is Tosilos in his usual garb, or Lidia in men’s clothing, is used as a manner in which to shed one’s limitations. In a similar manner, the other characters discover their agency through self-reflection. The book uses historical events such as the expulsion of the moors in Spain while interlacing characters and situations from Don Quixote to develop and elaborate Tosilos’ story. The narrative offers the reader an alternative and expanded outcome to the events witnessed in Don Quixote while providing a firsthand testimony of what life may have been like during the period. This process unites the various characters in the book by highlighting the subject matter and concerns that transcend time and continue to be relevant to a contemporary audience. [End Page 152] Linda González University of New Mexico Copyright © 2018 Board of Trustees of the University of Northern Colorado

Empirical models of annual post-fire erosion on mulched and unmulched hillslopes

Erosion is one of the primary land management concerns following wildfire. This study examines controls on post-fire hillslope-scale erosion for the 2012 High Park Fire in northern Colorado, develops simple empirical models for predicting post-fire sediment yields, and evaluates model performance on several nearby fires. From 2013 to 2015 we collected ground cover, rainfall, topographic, and sediment yield measurements from 29 convergent hillslopes; eight of these hillslopes had varying amounts of mulch applied to reduce erosion. From these data we examined correlations between annual sediment yield and three categories of predictor variables (ground cover, precipitation, and topography). Percent bare soil was the single largest control on sediment yield, followed by rainfall variables. Sediment yield generally decreased with flow path length, but the correlation was weak. The empirical models each predicted sediment yield with three variables: percent bare soil, one precipitation variable, and one topographic variable. The models had similar accuracy for the High Park Fire using varying combinations of precipitation and topographic variables (Nash-Sutcliffe coefficients 0.70–0.84). An empirical model predicting annual sediment yields as a function of percent bare soil, June–October precipitation, and the maximum flow path length had variable performance when applied to other fires in the same region, with predictions ranging from poor to good for individual fires and Nash-Sutcliffe coefficients of 0.26–0.32 for all fires combined. These tests show some promise for applying the empirical model to fires in the study region, but further model testing is needed to determine the range of conditions under which the model can be applied.

Ammonia emissions from a beef feedlot: Comparison of inverse modeling techniques using long-path and point measurements of fenceline NH3

Nitrogen (N) deposition in Rocky Mountain National Park, USA (RMNP) and adjacent alpine ecosystems has led to increased focus on ammonia (NH3) emissions from livestock operations in this region. A study was conducted at a commercial beef feedlot in Northern Colorado, USA to quantify NH3 fluxes, estimate emission factors (EFs), and evaluate measurement methodologies. Point and line-integrated fenceline NH3 measurements were taken over a 78-day study at a large feedlot east of RMNP focusing on transport towards the park. Ammonia fluxes were estimated using two inverse models, a backward Lagrangian stochastic approach (WindTrax) and a simpler inverse dispersion approach (FIDES) using input data from both NH3 datasets. Line-integrated NH3 concentrations were obtained from a long-path laser and single-point concentrations were collected with a cavity ring-down analyzer, both positioned on the downwind fenceline. Mean feedlot NH3 concentration (±1 standard deviation, σ) was 601±246μgm−3 (1013±421 ppbv), where peak values often exceeded several ppmv. Concentrations from the long-path sensor were slightly higher than the point sensor when winds were from the feedlot (p=0.0005), but 2.5 times less data were collected with the long-path instrument due to dust or laser-reflector alignment issues. Regardless of the model used, fluxes showed a diel pattern peaking in the afternoon with early morning minimums. Emissions varied more by inverse model than by sensor, with WindTrax emissions 25% higher than FIDES. Composite 24-h mean emissions (±1σ) from FIDES were 48±24μgm−2s−1 (EF=71±35ghd−1d−1), while WindTrax averaged 60±30μgm−2s−1 (EF=89±44ghd−1d−1) (p<<0.0001). Overall 24-h mean EF for the summer (across both models) was 80±39ghd−1d−1. When dietary N was considered (13.25% crude protein), based on 24-h composites FIDES estimated NH3-N released to the atmosphere to be 35.6% of fed-N, while WindTrax showed 44.6% fed-N. The overall mean across models was 40.0% fed-N.