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The National Center for Reliable Electric Power Transmission Test Facility
Get PDFGlobally, new technological solutions are being studied and developed by researchers in the field of power and energy systems. Before these solutions can be integrated into society as marketable products, thorough testing and validation of the design must be conducted. The National Center for Reliable Electric Power Transmission (NCREPT) is a unique high-power test facility located at the University of Arkansas, Fayetteville, AR, USA. NCREPT is a 12,000-square-foot laboratory space capable of testing power levels up to 6 MVA and offers testing at both the 480 V and 13.8 kV levels. NCREPT\u27s capabilities expand outside of the scope of simply high-power testing. NCREPT has also supported experimental testing for transportation electrification, hardware-in-the-loop, and cybersecurity applications. NCREPT has personnel with experience testing new technologies and has demonstrated its innovative approaches by being a part of four R&D 100 award-winning projects. This paper gives an extensive overview of NCREPT, highlighting its significance as a state-of-the-art testing laboratory
An Empirical Framework Characterizing the Metallicity and Star-formation History Dependence of X-Ray Binary Population Formation and Emission in Galaxies
Get PDFWe present a new empirical framework modeling the metallicity and star formation history (SFH) dependence of X-ray luminous (L ≳ 1036 erg s−1) point-source population X-ray luminosity functions (XLFs) in normal galaxies. We expect that the X-ray point-source populations are dominated by X-ray binaries (XRBs), with contributions from supernova remnants near the low luminosity end of our observations. Our framework is calibrated using the collective statistical power of 3731 X-ray detected point sources within 88 Chandra-observed galaxies at D ≲ 40 Mpc that span broad ranges of metallicity (Z ≈ 0.03–2 Z⊙), SFH, and morphology (dwarf irregulars, late types, and early types). Our best-fitting models indicate that the XLF normalization per unit stellar mass declines by ≈2–3 dex from 10 Myr to 10 Gyr, with a slower age decline for low-metallicity populations. The shape of the XLF for luminous X-ray sources (L ≳ 1038 erg s−1) significantly steepens with increasing age and metallicity, while the lower-luminosity XLF appears to flatten with increasing age. Integration of our models provides predictions for X-ray scaling relations that agree very well with past results presented in the literature, including, e.g., the LX–SFR–Z relation for high-mass XRBs in young stellar populations as well as the LX/M⋆ ratio observed in early-type galaxies that harbor old populations of low-mass XRBs. The model framework and data sets presented in this paper further provide unique benchmarks that can be used for calibrating binary population synthesis models
Market Assessment of Fortified Parboiled Rice in Burkina Faso
Get PDFMicronutrient deficiency remains a daunting issue in many parts of the world. Effective interventions are needed to deal with the problem, which should consider production and consumption traditions and trends to improve their success. Parboil rice is a growing staple in Burkina Faso, where micronutrient deficiency remains high. This paper assesses the market feasibility of fortified rice through parboiling using a limited-water soaking method. Our findings suggest that consumers are willing to pay a premium for fortified rice versus conventional parboiled rice after they are informed about the importance of the problem and the potential benefits of fortified rice. A stylized cost analysis also reveals that the cost of producing fortified rice using a limited-water soaking method could exceed the premiums consumers are willing to pay, and therefore that public intervention may be needed to improve the odds of adoption by consumers. The findings have implication beyond Burkina Faso, and could guide market development in other regions where production and consumption of parboiled rice is well established
Continuous Mowing Differentially Affects Floral Defenses in the Noxious and Invasive Weed \u3ci\u3eSolanum elaeagnifolium\u3c/i\u3e in its Native Range
Get PDFIn weeds, disturbance has been found to affect life history traits and mediate trophic interactions. In urban landscapes, mowing is an important disturbance, and we previously showed that continuous mowing leads to enhanced fitness and defense traits in Solanum elaeagnifolium, Silverleaf Nightshade (SLN). However, most studies have been focused on foliar defenses, ignoring floral defenses. In this study we examined whether continuous mowing affected floral defenses in SLN using mowed and unmowed populations in South Texas, their native range. We found flowers of mowed SLN plants larger but lighter than unmowed plants. Additionally, flowers on plants that were mowed frequently were both heavier and larger. Mowed plants had higher spine density and consequently unmowed flowers had higher herbivore damage. Additionally, early instar Manduca sexta fed on mowed flower-based artificial diets showed no difference in mass than the control and unmowed; however, later instars caterpillars on unmowed diets gained significantly more mass than the mowed treatment and control. Mowed plants had higher spine density which may shed light on why unmowed flowers experienced higher herbivore damage. We found caterpillars fed on high mowing frequency diets were heavier than those on low mowing frequency diets. Collectively, we show that mowing compromises floral traits and enhances plant defenses against herbivores and should be accounted for in management
AerialFormer: Multi-Resolution Transformer for Aerial Image Segmentation
Get PDFWhen performing remote sensing image segmentation, practitioners often encounter various challenges, such as a strong imbalance in the foreground–background, the presence of tiny objects, high object density, intra-class heterogeneity, and inter-class homogeneity. To overcome these challenges, this paper introduces AerialFormer, a hybrid model that strategically combines the strengths of Transformers and Convolutional Neural Networks (CNNs). AerialFormer features a CNN Stem module integrated to preserve low-level and high-resolution features, enhancing the model’s capability to process details of aerial imagery. The proposed AerialFormer is designed with a hierarchical structure, in which a Transformer encoder generates multi-scale features and a multi-dilated CNN (MDC) decoder aggregates the information from the multi-scale inputs. As a result, information is taken into account in both local and global contexts, so that powerful representations and high-resolution segmentation can be achieved. The proposed AerialFormer was benchmarked on three benchmark datasets, including iSAID, LoveDA, and Potsdam. Comprehensive experiments and extensive ablation studies show that the proposed AerialFormer remarkably outperforms state-of-the-art methods
Laughter and Effective Presidential Leadership: A Case Study of Ronald Reagan as the \u27Great Communicator\u27
Get PDFFormer United States President Ronald Reagan’s use of media and his charismatic connection with viewers earned him the moniker “the great communicator”. One aspect of his charisma, the influence of elicited laughter, during a highly critical 5-minute news story by CBS reporter Leslie Stahl during the 1984 US presidential election is examined here. Two experiments examining the effects of audience laughter on perceptions of charismatic leadership are reported. In the first experiment the effects of audience laughter in response to Reagan’s comments were investigated. Here, Reagan’s perceived warmth as an effective leader significantly diminished when strong laughter is removed, whereas perceptions of competence remained unaffected. The second study carried out on an older cohort replicated and extended the first in a pre-registered design by considering the perception of trait charisma. Here, the presence or absence of audience laughter did not affect judgements of charisma. Additionally, the affective response before, and then after, the presentation of the news story was measured. Emotions associated with a positive appraisal all decreased after being shown the news story while emotions associated negative appraisal all increased. However, only participant anger was significantly increased when audience laughter was removed. Taken together the findings of both studies converge on the fact that subtle changes in media presentation of political leaders can have a significant effect on viewers. The findings show that even after 40 years in office the social psychological effects of presidential charisma can still influence observers
Glass Ceilings, Step Stools, and Sticky Floors: The Racialized Gendered Promotion Process
Get PDFOrganizations play a central role in replicating societal inequalities. Despite theories of gendered and racialized organizations, evidence of unequal outcomes, and research on proposed mechanisms, we have few intersectional analyses demonstrating how the promotion process varies by race and gender across job levels in actual organizations. In this first-ever analysis of advancement in a U.S. firm by gender, race, and job, we run random effects logistic regression models on five years of novel longitudinal data from the software engineering workforce of a U.S.-based technology company. Results show intersectional performance-reward bias in patterns that help maintain the racialized gendered hierarchy so commonly observed in organizations: White men overrepresented at the top, women of color overrepresented at the bottom, and in the technology sector, men of Asian descent overrepresented in midlevel technical jobs and White women overrepresented in midlevel management positions. Findings suggest monitoring promotions by gender, race, and position to make visible biases that continue to impede workplace equity
Titration of Dietary Histidine During a 15 to 35 D Feeding Period in Male Cobb 500 Broilers
Get PDFDietary CP reductions in broilers can result in increased FCR when 6 or 7 feed-grade amino acids are allowed to enter formulation, and a partial explanation may be a dietary limitation of His. Histidine requirement data are sparce in the current body of literature, especially beyond 3 wk post-hatch. Therefore, a His dose-response experiment (expressed as a percentage of Lys) was conducted with male Cobb 500 broilers from 15 to 35 d post-hatch. A His deficient test diet was formulated to contain a digestible His to digestible Lys (dHis:dLys) ratio of 28.0%. Graded increments of L-His were added to the test diet to produce additional diets containing dHis:dLys ratios of 30.5, 33.0, 35.5, 38.0, 40.5, and 43.0%. A positive control (PC) diet was formulated to contain a dHis:dLys ratio of 38.0% met solely with intact protein. The PC diet outperformed the test diet in all live performance parameters and had a reduced peritoneal cavity fat yield. Linear responses to His were observed for final BW, BW gain, and FCR. In addition, a linear His response was observed for carcass yield and both linear and quadratic responses were observed for breast filet and tender yields. The 95% quadratic max method was used to derive the optimal dHis:dLys ratios of 39 and 37% for breast filet and tender yields, respectively. To accurately estimate quadratic asymptotes for live performance parameters, future His dose-response experiments may need to incorporate dHis:dLys ratios higher than 43%
Diet and Monensin Influence the Temporal Dynamics of the Rumen Microbiome in Stocker and Finishing Cattle
Get PDFBackground
Stocker cattle diet and management influence beef cattle performance during the finishing stage, but knowledge of the dynamics of the rumen microbiome associated with the host are lacking. A longitudinal study was conducted to determine how the feeding strategy from the stocker to the finishing stages of production affects the temporal dynamics of rumen microbiota. During the stocker phase, either dry hay or wheat pasture were provided, and three levels of monensin were administrated. All calves were then transported to a feedlot and received similar finishing diets with or without monensin. Rumen microbial samples were collected on d 0, 28, 85 during the stocker stage (S0, S28 and S85) and d 0, 14, 28, 56, 30 d before slaughter and the end of the trial during the finishing stage (F0, F14, F28, F56, Pre-Ba, and Final). The V4 region of the bacterial 16S rRNA gene of 263 rumen samples was sequenced. Results
Higher alpha diversity, including the number of observed bacterial features and the Shannon index, was observed in the stocker phase compared to the finishing phase. The bacterial amplicon sequence variants (ASVs) differentiating different sampling time points were identified. Dietary treatments during the stocker stage temporally impact the dynamics of rumen microbiota. For example, shared bacteria, including Bacteroidales (ASV19) and Streptococcus infantarius (ASV94), were significantly higher in hay rumen on S28, S85, and F0, while Bacteroidaceae (ASV11) and Limivicinus (ASV15) were more abundant in wheat. Monensin affected rumen microbial composition at a specific time. Transportation to feedlot significantly influenced microbiome structure and diversity in hay-fed calves. Bacterial taxa associated with body weight were classified, and core microbiotas interacted with each other during the trial. Conclusions
In summary, the temporal dynamics of the rumen microbiome in cattle at the stocker and finishing stage are influenced by multiple factors of the feeding strategy. Diet at the stocker phase may temporarily affect the microbial composition during this stage. Modulating the rumen microbiome in the steers at the stocker stage affects the microbial interactions and performance in the finishing stage
Engineering Central Substitutions in Heptamethine Dyes for Improved Fluorophore Performance
Get PDFAs a major family of red-shifted fluorophores that operate beyond visible light, polymethine dyes are pivotal in light-based biological techniques. However, methods for tuning this kind of fluorophores by structural modification remain restricted to bottom-up synthesis and modification using coupling or nucleophilic substitutions. In this study, we introduce a two-step, late-stage functionalization process for heptamethine dyes. This process enables the substitution of the central chlorine atom in the commonly used 4′-chloro heptamethine scaffold with various aryl groups using aryllithium reagents. This method borrows the building block and designs from the xanthene dye community and offers a mild and convenient way for the diversification of heptamethine fluorophores. Notably, this efficient conversion allows for the synthesis of heptamethine-X, the heptamethine scaffold with two ortho-substituents on the 4′-aryl modification, which brings enhanced stability and reduced aggregation to the fluorophore. We showcase the utility of this method by a facile synthesis of a fluorogenic, membrane-localizing fluorophore that outperforms its commercial counterparts with a significantly higher brightness and contrast. Overall, this method establishes the synthetic similarities between polymethine and xanthene fluorophores and provides a versatile and feasible toolbox for future optimizing heptamethine fluorophores for their biological applications