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Impact of Lighting Wavelength on Broiler Behavior, Health, and Performance
No full textLighting influences broiler production, health, and behavior. Due to their advanced visual system, avian species perceive a wide spectrum of light. The objective of this study was to investigate the effects of white (W, 350 to 780 nm) blue (B, 450 nm), and green (G, 560 nm) light on broiler production, processing performance, activity, fear, stress, blood cell profiles, tibiotarsi (tibia) morphology, and depth perception. Day-of-hatch by-product chicks from a Cobb 500 female line (N=600) were randomly assigned to 12 pens (N=4 treatment replicates). Body weight and feed consumption were recorded on day (D) 0, 14, 28, and 41, and feed conversion ratio was calculated. Depth perception was assessed using the Visual Cliff (VC) test (D1, D7, and D26), and fear was measured using the Tonic Immobility test (D12 and D33). Blood was drawn for leukocyte and plasma corticosterone concentrations (D21 and D41). On D41, thermal images of the head were taken to measure surface temperatures (eye and beak), and the bursa of Fabricius (bursa) was extracted for relative bursa weight. Accelerometers were adhered to birds Week 2 (D11 to D14) and Week 5 (D38 to D41), and left and right tibiotarsus (tibia) were extracted (D41) for morphology. After sampling, the remaining broilers were processed. Minimal differences were found for live production, stress, fear, or tibia morphology. Broilers in W were more likely to cross the depth line on D1 than B and G broilers during the VC test (P\u3c 0.0001), indicating poorer depth perception. Broilers in B had reduced lymphocyte (P=0.01) and T cell concentrations (P=0.009), suggesting poorer immune function. Activity was greatest for G broilers at Week 2 and lowest for W in Week 5 (P=0.0005). Broilers in the B group had the greatest rack and skin yields (P\u3c 0.0001), had the lowest fat pad yields (P=0.02) and greatest leg quarter yields (P=0.01), and W had the greatest breast (P=0.01) and white meat yields (P=0.001). These results suggest that light color can be strategically used to target production and welfare goals, with green light stimulating activity and white light improving processing yields
Evidence on the Quality of Segment Profit/Loss Disclosures and its Determinants
No full textInvestors have recently indicated that disclosed descriptions of segment profit/loss measures are useful, but insufficient. Clear and detailed descriptions are essential for helping investors understand the segment profit/loss measure employed, especially since these measures may not align with measures from the consolidated income statement under the “management approach.” To better understand investors’ concerns, I hand-collect data from segment profit/loss disclosures and develop a measure that captures a dimension of disclosure quality specific to this setting: the extent to which segment profit/loss disclosures effectively describe the segment profit/loss measure employed. The measure considers the level of detail provided and the ease with which users can determine the components of segment profit/loss. I find substantial variation in segment profit/loss disclosure quality across firms. The results of multivariate analysis suggest that segment profit/loss disclosure quality is driven by firm fundamentals and other characteristics of firms’ segment disclosures. Inconsistent with prior literature examining the extent of disaggregation into reportable segments, I find no evidence that proprietary or agency costs influence segment profit/loss disclosure quality. This suggests that more precise descriptions of the segment profit/loss measure employed do not carry the same risk of revealing proprietary information and agency problems. Finally, I find a substitute effect between mandatory and certain voluntary segment profit/loss disclosure decisions. This descriptive study presents baseline evidence on segment profit/loss disclosures across mandatory and voluntary disclosure frameworks that may be relevant to academics, financial statement users, and standard setters
Arkansas Corn and Grain Sorghum Performance Tests 2024
Get PDFCorn and grain sorghum performance tests are conducted each year in Arkansas by the University of Arkansas System Division of Agriculture. The tests provide information to companies marketing seed within the state and aid the Arkansas Cooperative Extension Service in formulating recommendations for producers.
The 2024 corn performance tests contained 44 hybrids and were conducted at the Northeast Rice Research and Extension Center (NERREC) at Harrisburg, the Lon Mann Cotton Research Station (LMCRS) near Marianna, the Rohwer Research Station (RRS) near Rohwer, and the Rice Research and Extension Center (RREC) near Stuttgart. The 2024 grain sorghum performance tests contained 16 hybrids and were conducted at the NERREC, the NEREC, the LMCRS, the RRS, and the RREC locations. The test location map for grain sorghum and corn can be found on page 42
“Are We There Yet?”: The Long Journey to Defining Motor Home Protections Under the Fourth Amendment
Get PDFFrom the time of the Revolutionary War, United States citizens have prioritized one thing over almost everything else: that “a man’s house is his castle.” This is immortalized in the Fourth Amendment’s prohibition against unreasonable and warrantless searches. The protections granted by the Fourth Amendment are not centered around the rights a person has in their property. Instead, “the principal object of the Fourth Amendment is the protection of privacy rather than property.” This protection is so important that the Supreme Court has been explicitly clear that warrantless searches should only be permitted in the most “exceptional” of circumstances. One way in which Fourth Amendment protections have been diminished is through the broad application of the “vehicle exception” to warrant requirements. At its inception, the vehicle exception applied only to traditional vehicles. However, as time went on, states did not uniformly apply the vehicle exception and were specifically divided regarding whether the exception should apply to motor homes. In order to resolve the disparate application, the Supreme Court stepped in with its decision in California v. Carney in 1985. The Court held in this case that any home that has wheels could be considered a vehicle under this exception. The only real check on this rule is that the Court instructed lower courts to only apply this rule in cases where the motor home functioned more like an automobile than a residence. Unfortunately, this standard is very confusing in application and does not consider motor homes that are equal parts automobile and residence.
This Note will describe the Court’s relevant decisions regarding the Fourth Amendment, leading to the decision to apply the vehicle exception to motor homes in California v. Carney. It will also suggest factors the Court should adopt to determine whether a motor home is considered a residence or a vehicle, in lieu of Carney’s confusing precedent. Necessarily, Part II will cover the general principles of the Fourth Amendment, the vehicle exception, and its application to motor homes through Carney. Part III will explain the modern-day reasons that the Carney decision should be revisited, including informal housing, the #VanLife practice of living in a van as one’s residence as well as their vehicle, and other non-traditional housing in a modern setting. Part III will also introduce the list of possible factors this Note suggests should replace the Carney decision
Razorback Analytics and Consulting: Driving Innovation
Get PDFUnder the identity of Razorbacks Analytics and Consulting, a consultation company, recommendations are made into the future of the vehicle manufacturing industry. Based on financial statement and industry data, Razorbacks Analytics and Consulting advises manufacturers about the uncertainty and high cost of transitioning vehicle lineups to electric powertrains. Recommendations are made based upon the observed data. Topics include: basic ratios, industry timing, supply chain issues, profitability, risk, and consumer issues
Experimental Study of Novel BCSA SCC Repair Materials and Implications on Corrosion in BCSA Concrete Structures
No full textSome current building codes for structural concrete allow the use of alternative cement concrete if their structural, durability, and fire performance can be shown to be comparable to portland cement (PC) concrete. One such alternative cement, belitic calcium sulfoaluminate (BCSA) cement, is a promising standalone replacement for portland cement given its lower global warming potential (GWP), fast setting time, and high early age compressive strength. These properties also make it an ideal repair material. But repair materials often need to be highly flowable and easy to consolidate and their performance when used to repair PC concrete structures must be understood. Additional questions remain regarding its durability performance, specifically surrounding its ability to protect reinforcing steel from corrosion. This study developed novel self-consolidating concretes (SCCs) with BCSA cement and characterized their fresh and hardened properties. Cement replacements with fly ash maintained the paste content of SCC mixtures while reducing the cement content. Increased fresh performance with increasing replacement rates were observed but were weighed against decreases in hardened properties. The structural performance of beams repaired with the developed BCSA cement SCC were evaluated in terms of load-deflection behavior, ultimate load, and return of capacity. Beams repaired in the flexural tension zone had capacities within 15% of the all-PC control beams at four hours and within 4% at seven days. Beams with end zone repairs had capacities within 6% and 3% of the PC control beams at four hours and seven days, respectively. To apply repair materials such as the BCSA SCC detailed in this study, the ability of such concrete to provide long term protection from corrosion to steel rebar must also be considered. The corrosion protection provided by BCSA cement concrete was evaluated using a test method developed to compare the effect of admixtures on PC concrete’s corrosion performance. The study’s goals were to examine the role of curing time in the corrosion results for BCSA cement and to measure the effectiveness of different methods to improve corrosion performance such as decreasing the water to cement ratio, increasing cover, and the use of surface sealers. The study found that durability testing of alternative cement concrete should be done considering the maturity of the concrete, rather than arbitrarily selecting a testing age based on PC based standards. Additionally, increasing clear cover depth, lowering w/cm, and using surface coatings such as silane, were effective in increasing corrosion protection
\u3ci\u3eIn vitro\u3c/i\u3e Investigation of Macrophage Functional and Metabolic Modulation
No full textMacrophages are a subset of immune cells with a variety of functions that are abundant in numerous tumor types such as colorectal and breast cancer. It has been suggested that macrophages may serve an important function as immune mediators in tumor behavior; however, macrophage activity is complex and remains not completely understood. The overall goal of this dissertation was to explore and exploit tumor-associated macrophage phagocytic function and the changes in their interactions with cancer cells in an in vitro mouse model and in 2D and 3D in vitro culture models. First, we wanted to better understand macrophage behavior under the various polarization states through longitudinal monitoring of metabolic and phagocytic effects of a murine macrophage cell line after exposure to various cytokine stimuli. Overall, the results of these studies indicate that autofluorescence imaging of endogenous metabolic cofactors can be a reliable method for monitoring the temporal and spatial dynamics of macrophage metabolism as they undergo activation after stimulation with cytokines as well as performing functions such as phagocytosis. Next, we created a 3D in vitro culture model that accurately resembled a 3D solid tumor while creating a novel analysis method to evaluate changes in multicellular spheroid structure and metabolism across spheroid micro-regions. Overall, the results of this study show that 3D multicellular spheroid models can provide a reliable solution for studying tumor biology, allowing for the evaluation of discrete changes across all spheroid microregions. Finally, we used the multicellular spheroid model as a preclinical model to test the effects of various therapeutic regimens (chemotherapy, immune checkpoint inhibitors, and phagocytosis checkpoints) to increase clinical understanding of combined regimens to off-set the side effects of traditional chemotherapy while stimulating immunogenic cell death. Results show that the combination of two immune checkpoint inhibitors in addition to a chemotherapy agent reduced spheroid growth (~46%), and reduced M2 macrophage expression and cellular proliferation while modulating cellular metabolism, ICD hallmarks, and phagocytic function. Overall, this study not only quantified microregional metabolic and structural changes in a simulated spheroid model but also quantified changes in ICD hallmarks and macrophage functional behavior. It was also found that relationships between spheroid structure and ICD hallmarks could exist after exposure to the combinatory regimen of immune checkpoint inhibitors and an ICD inducer
Quantifying the Effects of Urbanization on Stream Nutrient Loads and Decomposition
No full textUrban stream syndrome (USS) refers to the common symptoms of degradation in urban streams globally. Two symptoms of USS are increased nutrient and salt concentrations in streams, affecting ecosystem structure and function. Excess nutrients negatively impact freshwater ecosystems, placing downstream habitats at risk of eutrophication and harmful algal blooms. Excess salt runoff, derived from road salt application, is toxic to freshwater organisms and affects leaf litter decomposition, the base of aquatic food webs. Here, I aimed to quantify the effects of nutrient pollution and salinization on urban water quality and ecosystem function. Despite the widespread consequences of nutrient pollution, most research compares urban systems to pristine watersheds or focuses solely on nutrient concentrations in a single stream. This limits our understanding of how nutrient export varies spatially and temporally within a broader urban area. I quantified nutrient loads at a high spatiotemporal resolution in Fayetteville, Arkansas to determine the controls on nutrient export across the urban landscape. I collected biweekly nutrient samples (nitrate [N], soluble reactive phosphorus [P]) and streamflow at 20 sites, as well as five stormflow events at a subset of sites. Both N and P loads had a positive relationship (N: p\u3c0.0001, P: p\u3c0.0001) with subwatershed impervious cover and a negative relationship with subwatershed canopy cover (N: p\u3c0.001, P: p\u3c0.05). In contrast, riparian landscape characteristics were only seasonally important (e.g., canopy cover had a positive relationship with SRP in the spring). The effect of landscape characteristics on nutrient loads also varied across storm events. I also documented low spatial stability in nutrient loads, likely due to heterogeneity in land cover. Our research suggests urban water quality must be managed at the watershed scale to account for both the spatial heterogeneity of urban areas and seasonal variation in nutrient dynamics to effectively protect water quality. I also examined how traditional road salts and ‘eco-friendly’ alternatives (e.g., beet-brine) affect leaf litter decomposition, a key ecosystem function, using replicated recirculating stream mesocosms. I quantified microbial respiration of leaf biofilms, microbial conditioning (as leaf toughness), and decomposition (as mass loss) over a two-week period for a labile (sugar maple; Acer saccharum) and recalcitrant (post oak; Quercus stellata) leaf species under five deicer treatments: control, low-beet, high-beet, low-salt, and high-salt. I observed decreased decomposition rates for labile leaves in the high-beet treatment during first seven days of the experiment (high-beet-brine k = .007 d-1, control k = .022 d-1) treatment, most likely resulting from the addition of beet-based carbon. I saw microbial conditioning (an early indicator of decomposition) of recalcitrant leaves was increased by each of the deicing treatments, likely due to added Cl-. Overall, beet-brine had a larger effect on leaf litter decomposition than the paired treatment of traditional road salts. Further research is needed prior to the widespread implementation of beet-brine as an ‘eco-friendly’ alternative to traditional road salts. My thesis highlights the complex spatiotemporal dynamics of nutrient loss in urban streams and emphasizes that both traditional and eco-friendly management solutions require careful evaluation to support urban freshwater ecosystem function
Exploring Stigma Towards Postpartum Mothers with Opioid Use Disorder: Pre-Licensure Nursing Students\u27 Attitudes, Reflections, and Intervening in Peer Conversations
No full textObjective. To increase understanding of stigma in pre-licensure nursing students specifically related to OUD in postpartum mothers.
Methodology. Using a cross-sectional sample of baccalaureate pre-licensure nursing students (N=118), we measured stigma, knowledge, personal and professional experience, and comfort and confidence in intervening in stigmatizing conversations with peers surrounding postpartum mothers with OUD. Associations were examined between stigma, comfort and confidence, and knowledge along with differences between stigma of those based on their personal and professional experience. Further, participants provided responses to three open-ended reflection questions about experiences with and perceptions about OUD in postpartum mothers. Using a deductive and inductive coding procedure, qualitative responses were coded, and a thematic analysis was employed to determine overarching themes.
Results. Among the sample of baccalaureate pre-licensure nursing students, we found those with professional experience with a postpartum mother with OUD held more social distance than those without (p\u3c.05) on the subscale of the OMS-HC. Self-reported perceived postpartum OUD knowledge was positively related with comfort (p\u3c.05) and confidence (p\u3c.05) with intervening in stigmatizing conversations with peers. Also found was the positive association with objective OUD knowledge and comfort in peer conversations (p\u3c.05). Additionally, social distance was positively associated with comfort (p\u3c.01) and confidence (p\u3c.05) in intervening in stigmatizing conversations among their peers. Three themes emerged from reflections towards postpartum mothers with OUD, emerging perspectives, attitudinal influences, and a desire to care. The respondents shared both positive and negative attitudes towards postpartum mothers with OUD and discussed the presence of stigma and the overcoming of stigma with experiences, both professional and personal. The respondents inferred a desire to provide care, free from judgement, but were not always sure of the outcomes due to the influence of personal attitudes and judgments, resulting in conflict between personal attitudes and professional role.
Conclusion. Postpartum mothers with OUD are a stigmatized population, with negative impacts upon health outcomes. Stigma towards this population may come from pre-licensure nursing students within a variety of settings. Targeted, innovative education is needed to prevent and disrupt stigma in pre-licensure nursing students, to set a foundational standard of addressing stigma towards specific stigmatized populations, including postpartum mothers
Geospatial Modeling of Winter-Related Property Damage in Arkansas
Get PDFStorm Data, a monthly publication by the National Weather Service with records of weather events, reports on property damage caused by natural hazards. Since 1996, the database has included winter-related events. While the property damage data is considered incomplete, no other unique, public datasets report winter-related property damage at the county level. From 1996 to 2024, Arkansas ranked #1 in winter-related property damage. To understand the factors that are driving property damage and potentially reduce Arkansas’ vulnerability to it, three groups separated by temporal periods, i.e., “2000” (01/1996 - 06/2005), “2010” (07/2005 - 06/2015), and “2020” (07/2015 - 06/2024) are examined with geospatial modeling tools. The dependent variable is calculated as the total winter-related property damage during the period divided by the decade’s population, referred to as “damage per capita”. Sixteen potentially influential variables, including storm characteristics, demographic information, environmental data, and climatological data, are identified. Then, using the most influential variables for each group, the performance of ordinary least squares, spatial-lag, spatial-error, geographically weighted regression, and multi-scale geographically weighted regression models are compared. Lastly, using the most appropriate model, the variables’ influence on damage per capita is quantified by analyzing model coefficients for each group. Results show that different factors contributed to winter-related property damage per capita over space and time in Arkansas. Accounting bias, calculated as the percentage of reports with non-zero property damages, positively influenced all three models, serving as the most influential factor for the 2020 model. The 2010 model was most significantly influenced positively by the number of hours and the presence of deciduous forests and negatively by the median income, mean precipitation, and mean snowfall. The 2000 model was the best performing group, but its coefficients were only significant over small portions of the state. In southwest Arkansas, coefficients were negative and positive for the number of heavy snow reports and mean snowfall, respectively. Coefficients were negative for the number of hours in west-central Arkansas and positive for accounting bias along the western third of the state. These results are used to make recommendations to policymakers and emergency managers