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PHENOTYPIC AND MOLECULAR CHARACTERIZATION OF FUNGICIDE SENSITIVITY IN SEVERAL PENICILLIUM SPECIES CAUSING BLUE MOLD OF POME FRUITS IN THE PACIFIC NORTHWEST
Full text linkBlue mold, caused by Penicillium spp., poses a substantial threat to apples and pears during storage, resulting in about 50% fruit loss in the Pacific Northwest (PNW). The primary approach to managing blue mold is through postharvest applications of four fungicides, i.e., thiabendazole (TBZ), difenoconazole (DIF), pyrimethanil (PYR), and fludioxonil (FDL). Between 2016 and 2018, a total of 162 Penicillium isolates were collected from decayed apples and pears from multiple packinghouses in the states of Washington and Oregon. These isolates included 31 P. expansum isolates and 131 isolates of 13 other Penicillium species referred to as non-expansum isolates. In vitro conidial germination and mycelial growth inhibition assessments were conducted to establish EC50 values of 162 Penicillium isolates to TBZ, DIF, PYR, and FDL. The results revealed a high in vitro tolerance of several non-expansum isolates compared to P. expansum isolates. Overall, the EC50 values were particularly high (>500 ฮผg/ml) for TBZ and FDL in non-expansum species including P. solitum, P. roqueforti, P. commune, P. paneum, P. crustosum and P. palitans, moderate (>10 ฮผg/ml) for PYR, and low (<2 ฮผg/ml) for DIF. Reduced sensitivity to multiple postharvest fungicides was observed for several Penicillium spp. The recommended label rates of TBZ, PYR, and FDL proved ineffective in inhibiting blue mold decay from at least six Penicillium species on detached apples after five months of storage at 1.5ยฐC. Sequencing of the ฮฒ-tubulin gene revealed mutations at codon 167 (F167Y) in 16TBZ-resistant isolates of six Penicillium species. Additionally, concurrent mutations were found at codons 198 and 240 in P. roqueforti and P. paneum isolates with high EC50 values. Sequencing of the CYP51, MDL1, NIKA and OS1 genes, known to confer resistance to DIF, PYR, and FDL in other fungi, identified several mutations that were not consistently linked to in vitro sensitivity and will necessitate further investigation. The high in vitro tolerance and the control failure observed on fruit highlight the potential risk posed by several โnon-expansumโ Penicillium species to pome fruit packers
Steam Methane Reforming TEA v1.0
No full textThis spreadsheet is a techno-economic analysis model that estimates the minimum selling price of hydrogen (MSPH) for a steam methane reforming facility, using ratio factors to estimate operating and maintenance costs (OSBL)and user-selected, location-specific assumptions. Users configure scenarios using drop-down menus and editable input cells. The model then generates MSPH results on the Output tab. Additionally, it calculates the carbon intensity of the hydrogen pathway and allows users to optionally account for incentives and carbon capture and storage configurations within each scenario
Cover crop mixtures vs. monoculturesย what the research shows
No full textThe primary challenge in agriculture remains how to provide enough food for a still-growing population without threatening future food production and without expanding agricultural land. Cover crops can help us achieve this by controlling soil erosion, improving soil health, nutrient cycling, weed suppression, and through other benefits. However, there is ongoing discussion about whether planting diverse cover crop mixtures offers greater advantages than single-species cover crops. This publication summarizes recent research findings to support informed decisions about cover crop selection
The Experiences of Native Americans After A Nonfatal Suicide Event and Healthcare
Full text linkNative Americans make up only 2% of the population, yet have one of the highest suicide rates of any ethnic or racial group in the United States. High suicide rates in Native American communities can be attributed to a number of factors including historical trauma, genocide, and lack of access to healthcare. The purpose of this study was to explore the experiences of Native Americans who had a nonfatal suicide attempt and their encounter with healthcare providers prior to receiving the Caring Contacts intervention.Five hundred and fifty-four Native American participants provided responses to three qualitative questions from the Client Satisfaction Questionnaire- 8 prior to receiving a culturally adapted suicide intervention. Thematic Analysis was used to interpret and identify patterns of meaning in the words of the Native participants. Through team analysis of the transcripts, an understanding of the participantโs experiences was developed. Thematic Analysis, with its idiographic focus, allowed for insight into the Native participantsโ experience and how they make sense of their experiences as a Native person that has attempted suicide. The information provided during the baseline interviews of the Native participants allowed for extrapolation of meaningful themes related to Communication (subthemes: Counseling, Characteristics of Communication, and Role of Staff Communication), Access (subthemes: Care Received, Access to Medications, and Access to Services), and Connection (subthemes: Provider-Patient Relationship, Coping Skills, Provider Consistency, and Culturally Congruent Care). The themes informed the patient perspective of the healthcare received.Healthcare workers, specifically nurses, may be the first person a Native person engages with post suicide attempt. It is imperative that nurses and all healthcare workers provide care to the Native patient after a suicide attempt that is culturally sensitive and void of stigma associated with suicide, race, ethnicity, and culture
SUBSTANCE USE RELATED LICENSURE DISCIPLINE IN NURSESย FACTORS AND TRENDS IN THE RETURN-TO-WORK PROCESS
Full text linkBackground: Substance use among Registered Nurses has significant consequences that can extend into their workplace and patient care delivery. Limited research has explored substance use in nurses and the return-to-work process that RNs must engage in after licensure discipline related to substance use. With the looming nursing shortage, it is critical to understand the factors that may be associated with substance use related licensure discipline and the barriers that RNs encounter when attempting to return to work. More research is needed to create evidence-based pathways that can facilitate successful reintegration to the workplace for RNs.Aims: 1) Describe the current state of substance use related licensure discipline among RNs in the United States in 2018-2023; 2) Describe and analyze RN self-reported barriers in returning to work after licensure discipline related to substance use; 3) Describe and analyze RN self-reported facilitators in returning to work after licensure discipline related to substance useMethods: The multi-method research, which was guided by the Neuman Systems Model, includes three studies: a retrospective analysis of substance use-related licensure discipline trends and characteristics using the National Practitioner Data Bank (Manuscript 1) and two Group Concept Mapping studies exploring the self-reported barriers (Manuscript 2) and facilitators (Manuscript 3) in the return-to-work process for nurses after licensure discipline related to substance use.Results: Comparisons of licensure discipline trends and characteristics between 2018 and 2023 found census region, age, and years of nursing experience to be significant variables across statistical tests. Substance use monitoring, as a disciplinary outcome, was the only action to have a statistically significant increase over the time period studied. In examining barriers and facilitators in the return-to-work process for nurses with a substance use monitoring agreement, 11 distinct themes emerged through the Group Concept Mapping studies. The five themes within the barriers were Work-Related Challenges, Financial Burden, Administrative Challenges, Impact on Mental Health, and Peer and Co-Worker Support. The six themes within facilitators were Monitoring Recommendations, Autonomy and Self-Efficacy, Caring for the Caregivers/Prevention, Nurses Helping Nurses, Reintroduction to Practice, and Positive Employer Factors.Significance: These results demonstrate significant regional differences in the application of licensure discipline, suggesting inequities likely exist for RNs regarding substance use. Using the voice and experiences of nurses affected by disciplinary actions, this research allowed for examination of their perceptions and values while also identifying ways to support their priorities. These studies lay the foundation for continued policy examination to support equitable disciplinary actions for nurses after substance use as well as programmatic evaluation and development for effective monitoring programs
The impact of soil erosion on corn yields: A spatial regression analysis
No full textThis study examines the impact of soil erosion on corn (Zea mays L.) yield across counties in the US Midwest. Using a novel county-level panel dataset that includes information on water erosion and corn yield, we analyze the direct and spatial spillover effects of erosion using a spatial regression framework. We find that increases in soil erosion have a statistically significant negative impact on corn yield. In addition, we find evidence of significant spatial spillover effects, indicating that erosion in one county can adversely affect agricultural productivity in surrounding areas. These findings confirm that the negative effects of soil erosion extend beyond the site of origin and are spatially diffused across regions. This study provides new empirical evidence on the broader yield-related consequences of soil erosion and highlights the importance of landscape-level conservation strategies to mitigate its long-term agricultural impacts
ADVANCING PROTEOMICS APPROACHES TO STUDY STRESS RESPONSE AND METABOLISM IN OLEAGINOUS BASIDIOMYCETE YEASTS
Full text linkBasidiomycetes are vital to environmental decomposition of plant litter. Oleaginous basidiomycete yeasts are particularly attractive for biorefineries given their capabilities to utilize diverse biomass-derived carbon sources, to store carbon as lipids, and to synthesize biofuels, chemicals, and proteins. However, ascomycete yeasts are frequently chassis for metabolic engineering and models for studying the oleaginous phenotype. For basidiomycete yeasts, the full extent of their metabolic capabilities and intricacies of metabolic regulation are understudied.This dissertation describes original research concerning nutrient-induced stress response and metabolic regulation in two oleaginous basidiomycete yeasts: Rhodotorula toruloides and Cutaneotrichosporon oleaginosum. Both these yeasts accumulate lipids as a result of nitrogen limitation, which is the primary bioprocessing strategy used for oil production. Their ability to accumulate lipids and the quality of the resulting oil is affected by the type and availability of carbonaceous nutrients. As building blocks of life, limiting access to these nutrients requires a cellular responses to adapt and survive. The resulting phenotypic changes are largely due to alterations in protein expression and regulation. In this work, advanced proteomics approaches are harnessed to provide insights into how cellular responses are orchestrated at the molecular level.This work demonstrates the first example of redox proteomics applied to an oleaginous yeast to study a protein modification called cysteine oxidation, which is an important type of cell signal and regulatory mechanism in response to nitrogen limitation. Antioxidants are indispensable for combatting protein oxidation during nutrient-limited stress but also protect fungi against reactive compounds they produce to deconstruct lignin, which is the most carbon-dense component of plant cell walls. Unlike previous research endeavors that focused on filamentous fungi and bacteria, the lignin-degrading capacity of a basidomycete yeast was studied herein. Whole-cell 2D 1H-13C NMR and fluorescence microscopy were used to analyze lignin structural changes and lignin transport, whereas novel secretomics and cellular proteomics methods were employed to highlight enzymes putatively involved lignin degradation. Due to the recalcitrance of lignin, the biochemical phenotype of the yeast cultivated with alkali-purified lignin was nonetheless reminiscent of carbon limitation. Taken together, this dissertation furthers our fundamental understanding of biotechnologically-relevant basidiomycete yeasts and provides original targets for genetic engineering
SOIL COMPACTION IMPACT ON SOIL FUNCTIONS IN DRYLAND PRODUCTION SYSTEMS OF THE PACIFIC NORTHWEST
Full text linkSoil compaction in agriculture is often overlooked and rarely measured. Once compaction occurs, restoring soil functionality is challenging and costly, and it varies in effectiveness based on soil texture and cropping system. Remediation techniques, including mechanical loosening and crop rotations aimed at breaking compacted layers, lack consistent validation due to limited reliable measurement tools. Compaction has been shown to reduce yield, primarily by limiting water availability; however, these effects fluctuate with weather conditions. The below-ground impact of compaction on roots and soil properties remains poorly understood, especially in rain-fed systems. This study addresses these gaps by linking compaction to critical agricultural functions, including yield, root growth, and soil water storage. Additionally, we introduced a field-scale protocol (10-500 ha) for measuring and mapping compaction. Compacted soils generally had higher water content but showed a decline of up to 20 mm in water depletion at 0-1.05 m depths. Increased compaction correlated with reduced root length density in wheat roots across all diameters (0.30-1.05 m), whereas in canola, responses were less consistent. Root length density, which was explained 9-42% by volumetric water content, showed stronger correlations at shallower depths, and reductions in root density were associated with a 0.14 Mg ha-1 yield decrease. High-traffic areas showed quality losses, with canola yield decreasing by 0.5 Mg ha-1 and wheat by 1.2 Mg ha-1, along with reduced canola oil content (-1.9%) and lower test weights in wheat (-0.78 lb bu-1). Compaction also raised grain protein content by 3.3% in canola and 1.1% in wheat. We implemented pedotransfer functions using penetrometer force, depth of insertion, and soil water content for bulk density predictions, alongside environmental and terrainvariables from proximal and remote sensing. Models achieved RMSEs of 0.09-0.81 Mg m-3 for profile and spatial bulk density predictions, though driest site predictions were less accurate. Our mapping protocol offered insights but also revealed challenges in accounting for spatial variability, suggesting the need for enhanced sampling. As the first study to link compaction with yield quality reductions, we propose that future research include quality traits as additional indicators of compaction. Furthermore, the potential impact of reduced root growth and biomass on carbon sequestration requires exploration
Mechanisms driving altitude- and latitude-dependent air quality variations from high-altitude NOx emissions
No full textThe environmental impact of nitrogen oxide (NOx) emissions varies with emission altitude and latitude. NOx emissions from subsonic aviation (9-12 km) contribute to net global ozone formation, whereas those from supersonic aircraft (above 14 km) lead to net global ozone depletion. However, the effects of NOx emission altitude on surface air quality remain understudied. We evaluate how NOx emissions at different altitudes (8-22 km) and latitudes influence near-surface concentrations of two known air pollutants: ozone and fine particulate matter (PM2.5). Using the global chemical transport model GEOS-Chem, we find that NOx emissions of 1 Tg N yr-1 at 8-10 km (30-60 degrees N) increase surface ozone (population-weighted) by 0.52 ppb and surface PM2.5 by 35 ng m-3, whereas emissions at 20-22 km reduce surface ozone by 1.73 ppb and increase surface PM2.5 by 310 ng m-3; this is nine times the PM2.5 increase per unit NOx from lower-altitude emissions. These effects stem from altitude-dependent mechanisms: at lower altitudes typical of subsonic aviation, NOx emissions increase upper tropospheric ozone which leads to enhanced surface ozone and nitrate aerosol. However, when emitted at higher altitudes NOx instead depletes ozone, permitting more ultraviolet light to reach the troposphere which boosts OH production and accelerates production of sulfate aerosol while destroying near-surface ozone. Our findings suggest that NOx emissions from high-altitude sources, including supersonic aircraft may not only contribute to stratospheric ozone depletion but also cause larger changes (albeit of mixed sign) in surface air quality than subsonic aviation per unit of NOx emitted
Assessing a sustainable aviation fuel supply chain from winter canola and its carbon intensity considering feedstock yield variations
No full textReplacing conventional aviation fuel (CAF) with sustainable aviation fuel (SAF) has been suggested as a vital means to decarbonize the aviation industry. We considered winter canola a feedstock for SAF production through the hydro-processed esters and fatty acids pathway in the Southeast United States. We incorporated feedstock yield variations in a stochastic mixed-integer linear programming model to optimize the SAF supply chain. Results suggest the potential SAF production for Nashville International Airport (BNA), from an existing oil extraction mill and 0.19 million hectares (ha) of winter canola cultivation, range from 129 million liters yearly (MLY) to 246 MLY with a 90ย % likelihood. With additional investment and expanded winter canola cultivation to 0.61 million ha, the expected SAF supply to BNA could increase to 348 MLY. An additional 212 MLY can be supplied to Memphis International Airport. After considering the co-product revenues, the expected breakeven cost for SAF is $1.1 per liter. The SAF's carbon intensity falls into the range from 31ย g of carbon dioxide equivalent per megajoule of fuel (g CO2e MJโ1) to 43ย g CO2e MJโ1, with 90ย % probability, which is at least 50ย % lower than CAF