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This study aimed to develop poly(lactic acid) (PLA) biodegradable film containing sodium nitrite and α-tocopherol, and to examine its effect on dark-cutting beef color attributes. Using a twin-screw extruder, PLA pellets were manufactured as a low-concentration (LC) PLA pellet containing 0.12% sodium nitrite and 0.5% α-tocopherol or a high-concentration (HC) PLA pellet containing 0.6% sodium nitrite and 2.5% α-tocopherol. Extruded PLA pellets were oven-dried before being compressed and molded into film sheets using a hot press. In this study, 7 normal-pH and 7 dark-cutting strip loins were selected from a commercial processor. Loins were sliced into 2.54-cm thick steaks and randomly assigned to the respective loin-type treatments. The packaging treatments include normal-pH polyvinyl chloride (PVC), dark-cutting PVC, dark-cutting vacuum, LC-PLA dark-cutting in vacuum, and HC-PLA dark-cutting in vacuum. Normal-pH steaks were packaged with PVC overwrap, while dark-cutting control steaks were packaged in PVC overwrap and vacuum-sealed. The respective PLA films (LC or HC) were placed directly on the surface of the dark-cutting steak surface before vacuum packaging, resulting in LC-PLA and HC-PLA treatments. All steaks were placed in a simulated retail dis-play maintained at 2±1°C for 6 d, during which their surface color was evaluated every 24 h using a HunterLab spectrophotometer and a trained panel (n=6). Half of the steaks were removed from display on d 5 and cooked to 71°C on a George Foreman grill to evaluate the cooked color. The remaining steaks were evaluated on d 6 for microbial growth and lipid oxidation. A significant increase (P0.05) compared to dark-cutting steaks in control vacuum packages (without nitrite). There were no differences (P>0.05) in aerobic plate count and lipid oxidation between nitrite-embedded and control vacuum dark-cutting treatments. Results indicate that using lower concentrations of sodium nitrite (0.12%) andα-tocopherol (0.5%) in PLA films can help improve the surface color of raw dark-cutting steaks while minimizing unpleasant cooked color associated with nitrite-embedded film.

Breeding sorghum to withstand droughts is pivotal to secure crop production in regions vulnerable to water scarcity. Limited transpiration (LT) restricts water demand at high vapor pressure deficit, saving water for use in critical periods later in the growing season. Here we evaluated the hypothesis that LT would increase sorghum grain yield in the United States. We used a process-based crop model, APSIM, which simulates interactions of genotype, environment, and management (G × E × M). In this study, the G component includes the LT trait (GT) and maturity group (GM), the EW component entails water deficit patterns, and the MP component represents different planting dates. Simulations were conducted over 33 years (1986-2018) for representative locations across the US sorghum belt (Kansas, Texas, and Colorado) for three planting dates and maturity groups. The interaction of GT x EW indicated a higher impact of LT sorghum on grain for late drought (LD), mid-season drought (MD), and early drought (ED, 8%), than on well-watered (WW) environments (4%). Thus, significant impacts of LT can be achieved in western regions of the sorghum belt. The lack of interaction of GT × GM × MP suggested that an LT sorghum would increase yield by around 8% across maturity groups and planting dates. Otherwise, the interaction GM × MP revealed that specific combinations are better suited across geographical regions. Overall, the findings suggest that breeding for LT would increase sorghum yield in the drought-prone areas of the US without tradeoffs.

ABSTRACT Enterohemorrhagic Escherichia coli (EHEC) is a group of pathogenic bacteria responsible for several foodborne-associated outbreaks of human diarrheal disease. Although EHEC is a major cause of morbidity as well as the condition known as hemolytic uremic syndrome, linked to the production of Shiga toxins (Stx), there are no licensed vaccines approved for human use. Fully assessing vaccine efficacy against EHEC infections is challenging because conventional adult mice are inherently resistant to EHEC infection and do not develop hallmark symptoms of the disease. Therefore, in this study, we utilized a strain of the murine pathogen Citrobacter rodentium that has been lysogenized to produce Stx2d, which consistently causes lethal infection and other measurable disease outcomes following oral challenge, to further evaluate the protective efficacy of our previously formulated EHEC gold nanoparticle (AuNP) vaccines. Using this model, along with a non-Stx2d-producing C. rodentium strain, we assessed the protection conferred by AuNPs conjugated to three EHEC antigens: EscC, LomW, and intimin (Eae). We demonstrated that intranasally immunizing mice with AuNP-Eae provides partial protection against mortality caused by Stx2d-producing C. rodentium and that AuNP-EscC and AuNP-Eae moderately reduce intestinal burden of the non-Stx2d-producing C. rodentium strain compared with adjuvant-only-treated mice. Additionally, the AuNP-protein vaccines induced antigen- and pathogen-specific serum IgG and fecal IgA against both EHEC and C. rodentium while in vitro functional assays indicate that the elicited antibodies are bactericidal and prevent adherence of C. rodentium to intestinal epithelial cells. We propose that C. rodentium murine data could translate into correlates of protection. IMPORTANCE Enterohemorrhagic Escherichia coli (EHEC) remains an important cause of diarrheal disease and complications worldwide, especially in children, yet there are no available vaccines for human use. Inadequate pre-clinical evaluation due to inconsistent animal models remains a major barrier to novel vaccine development. We demonstrate the usefulness of Stx2d-producing Citrobacter rodentium in assessing vaccine effectiveness because it more closely recapitulates human disease caused by EHEC.

The population decline of American Eels (Anguilla rostrata) in North America represents multiple crises: ecosystem destruction, industrial impact, forced relocation, cultural disenfranchisement, water degradation, and biodiversity loss. Once a key component of Indigenous societies, trade routes, economies, and ceremonial cycles, today Eels experience migration barriers and habitat degradation stemming from waterway abuse and land use alteration. The development of agricultural and industrial social norms has led to dramatic reductions in Eel populations across North America. Fishery agencies familiar with Eel life cycles often list species as depleted, and disappearance of Eels is well-accepted in all sectors. Related species of Anguillid Eels are in decline globally. Yet, in some areas, American Eels continue to migrate, grow, and even thrive. This article proposes Eel continuity as powerful survivorship in troubled times, a counter-narrative to overwhelming stories of environmental pessimism. Although Eels are often discredited, reviled, and disrespected by Americans and Canadians alike, their contributions to marine and aquatic zones are underestimated and poorly understood. This article employs a reflexive method of dialogue and commentary from two Eel advocates with interdisciplinary training and backgrounds, who envision relational, wisdom-based practices that meaningfully integrate Indigenous, community, academic, and other forms of knowledge about Eels and about water.

Background: Lyme disease (LD) and other tick-borne diseases are emerging across Canada. Spatial and temporal LD risk is typically estimated using acarological surveillance and reported human cases, the former not considering human behavior leading to tick exposure and the latter occurring after infection. Objectives: The primary objective was to explore, at the census subdivision level (CSD), the associations of self-reported tick exposure, alternative risk indicators (predicted tick density, eTick submissions, public health risk level), and ecological variables (Ixodes scapularis habitat suitability index and cumulative degree days > 0 °C) with incidence proportion of LD. A secondary objective was to explore which of these predictor variables were associated with self-reported tick exposure at the CSD level. Methods: Self-reported tick exposure was measured in a cross-sectional populational health survey conducted in 2018, among 10,790 respondents living in 116 CSDs of the Estrie region, Quebec, Canada. The number of reported LD cases per CSD in 2018 was obtained from the public health department. Generalized linear mixed-effets models accounting for spatial autocorrelation were built to fulfill the objectives. Results: Self-reported tick exposure ranged from 0.0 % to 61.5 % (median 8.9 %) and reported LD incidence rates ranged from 0 to 324 cases per 100,000 person-years, per CSD. A positive association was found between self-reported tick exposure and LD incidence proportion (ß = 0.08, CI = 0.04,0.11, p

Tau aggregates contribute to neurodegenerative diseases, including frontotemporal dementia and Alzheimer's disease (AD). Although RNA promotes tau aggregation in vitro, whether tau aggregates in cells contain RNA is unknown. We demonstrate, in cell culture and mouse brains, that cytosolic and nuclear tau aggregates contain RNA with enrichment for small nuclear RNAs (snRNAs) and small nucleolar RNAs (snoRNAs). Nuclear tau aggregates colocalize with and alter the composition, dynamics, and organization of nuclear speckles, membraneless organelles involved in pre-mRNA splicing. Moreover, several nuclear speckle components, including SRRM2, mislocalize to cytosolic tau aggregates in cells, mouse brains, and brains of individuals with AD, frontotemporal dementia (FTD), and corticobasal degeneration (CBD). Consistent with these alterations, we observe that the presence of tau aggregates is sufficient to alter pre-mRNA splicing. This work identifies tau alteration of nuclear speckles as a feature of tau aggregation that may contribute to the pathology of tau aggregates.

The ranger workforce is currently characterized by an extreme gender skew. Exact data—or even reliable estimates—are scarce, but the general understanding is that only 3–11% of the global ranger workforce is female, with considerable local variation (Belecky et al. 2019). Although consideration of the gender context for a workforce often starts with numbers, achieving greater gender balance requires a much more comprehensive understanding of the problems and a wide-net approach to solutions. Bringing women into the ranger workforce is an important human rights and equality goal in itself. Further, there is evidence that women bring skill sets and strengths to the ranger workforce that are different from those of men. Bringing gender equality into the workforce can improve conservation, relationships with communities, park management, and wildlife management. The Chitwan Declaration (World Ranger Congress 2019) commits to broad gender-related goals: gender-equal opportunities in hiring, pay, and promotion in the ranger workforce, as well as appropriate measures to provide safety and support for female rangers. This paper, based in part on interviews with men and women in the current ranger workforce, analyzes the state of the gender imbalance in the ranger workforce, provides a contextual assessment, and advances recommendations for moving towards these Chitwan goals.

Citizen science, an emerging research tool employed worldwide, can encourage nonprofessionals to engage in scientific exploration. Additionally, the research strategy presents great potential to serve as a learning platform for students, supporting diverse contributions to science on public lands. Citizen science also has potential to encourage connections to place. This article focused on the Rocky Mountain Sustainability and Science Network (RMSSN), a program using citizen science projects as a strategy to promote student place-based learning in U.S. National Parks. This study not only examines the practice of leveraging citizen science for learning, but it also assesses participants' place attachment as a result of the experience using a mixed methods approach. Place attachment is defined as the intersection of two elements: place identity which considers the emotional bonding to a place, as well as place dependence, which encompasses the function of the place for attachment. The Place Attachment Inventory (PAI) was used to quantitatively evaluate student connections with the parks following the experience, and focus groups yielded additional insights into the learning experience. Findings indicated that the short-term citizen science experience supported learning among a diverse group of participants, which resulted in an enhanced appreciation and deeper connections with the parks, and with participants recognizing them as special places.

Enterohemorrhagic E. coli (EHEC) is a group of pathogenic bacteria that is associated with worldwide human foodborne diarrheal illnesses and the development of hemolytic uremic syndrome, a potentially deadly condition associated with Shiga toxins (Stxs). Currently, approved vaccines for human prophylaxis against infection do not exist, and one barrier preventing the successful creation of EHEC vaccines is the absence of dependable animal models, including mice, which are naturally resistant to EHEC infection and do not manifest the characteristic signs of the illness. Our lab previously developed gold nanoparticle (AuNP)-based EHEC vaccines, and assessed their efficacy using Citrobacter rodentium, which is the mouse pathogen counterpart of EHEC, along with an Stx2d-producing strain that leads to more consistent disease kinetics in mice, including lethality. The purpose of this study was to continue evaluating these vaccines to increase protection. Here, we demonstrated that subcutaneous immunization of mice with AuNPs linked to the EHEC antigens EscC and intimin (Eae), either alone or simultaneously, elicits functional robust systemic humoral responses. Additionally, vaccination with both antigens together showed some efficacy against Stx2d-producing C. rodentium while AuNP-EscC successfully limited infection with non-Stx2d-producing C. rodentium. Overall, the collected results indicate that our AuNP vaccines have promising potential for preventing disease with EHEC, and that evaluation of novel vaccines using an appropriate animal model, like C. rodentium described here, could be the key to finally developing an effective EHEC vaccine that can progress into human clinical trials.

Grinding is a finishing process typically done in most metallic manufacturing centers, primarily to achieve precision and surface improvement. Currently, the grinding process of titanium alloys generally requires flood coolant application. Electron Beam Powder Bed Fusion (EB-PBF) is an additive manufacturing process that uses an electron beam as the heat source to melt and fuse powder particles to build layer by layer to build a three-dimensional component. Grinding is a major secondary process applied to additively manufactured metals, but with the current methodologies, grinding may impart tensile residual stress on the surface, and thus the performance of the material under fatigue conditions is reduced. In this paper, a targeted cutting fluid application approach for grinding an additively manufactured titanium alloy is used to possibly impart a compressive residual stress upon the subsurface while also providing an improved surface roughness. This study uses samples ground with a traditional flood coolant and samples with targeted cutting fluid applications developed by the researchers. Metrics such as surface residual stress, surface roughness, microstructure, and microhardness were used to determine imparted qualities using the various grinding cooling methodologies. The results show that the subsurface maximum principal residual stresses decreased by 108%, the average surface roughness decreased by 33%, and the microhardness at 5 μm increased by 1% using targeted air as the cutting fluid compared to flood cooling while grinding additively manufactured Ti6Al4V. Overall, the targeted grinding cooling fluid application induced compressive subsurface residual stresses and reduced the average surface roughness.

Summary: Climate and land use change are two of the largest drivers of worldwide biodiversity loss, but detecting drivers of insect decline is more complex. Online data sources can elucidate such responses while identifying systematic data gaps. Using a systematic review, we found 119 studies that document bumble bee and butterfly responses to climate change. While bee literature was limited, there is high confidence that species are emerging earlier (∼17 days), mismatching with floral resources (100% of studies), and changing range distributions (−25%). More butterfly literature was available but did not yield consistent responses. Evidence shows earlier emergences (∼5 days), decreasing range distributions (−19%), and population shifts amongst generalist (87% increase) versus specialist (65% decrease) groups. We argue that the effect of changing climates on floral emergence, abundance, and distribution may be more significant than the impact of climate change on biodiversity; however, further research is required, particularly within the Southern Hemisphere.

Variability in ALS disease onset and progression are poorly understood. Our work identifies three distinct molecular states in post-mortem tissue that capture some of the observed differences in patient age of onset and survival.

Abstract Background Despite widespread restrictions on residents’ mobility to limit the COVID-19 pandemic, controlled impact evaluations on such restrictions are rare. While Colombia imposed a National Lockdown, exceptions and additions created variations across municipalities and over time. Methods We analyzed how weekend and weekday mobility affected COVID-19 cases and deaths. Using GRANDATA from the United Nations Development Program (UNDP) we examined movement in 76 Colombian municipalities, representing 60% of Colombia's population, from March 2, 2020 through October 31, 2020. We combined the mobility data with Colombia’s National Epidemiological Surveillance System (SIVIGILA) and other databases and simulated impacts on COVID-19 burden. Results During the study period, Colombians stayed at home more on weekends compared to weekdays. In highly dense municipalities, people moved less than in less dense municipalities. Overall, decreased movement was associated with significant reductions in COVID-19 cases and deaths two weeks later. If mobility had been reduced from the median to the threshold of the best quartile, we estimate that Colombia would have averted 17,145 cases and 1,209 deaths over 34.9 weeks, reductions of 1.63% and 3.91%, respectively. The effects of weekend mobility reductions (with 95% confidence intervals) were 6.40 (1.99–9.97) and 4.94 (1.33–19.72) times those of overall reductions for cases and deaths, respectively. Conclusions We believe this is the first evaluation of day-of-the week mobility on COVID-19. Weekend behavior was likely riskier than weekday behavior due to larger gatherings and less social distancing or protective measures. Reducing or shifting such activities outdoors would reduce COVID-19 cases and deaths.

This article examined a unique collaborative initiative between a team of graduate level faculty to improve the quality of course development and delivery using a collaborative review process. The collaborative review of teaching has become a widely accepted means for assuring quality distance learning coursework and for the purpose of evaluating the effectiveness of online teaching. The criteria of the "Quality Online Learning and Teaching (QOLT) Assessment for Peer Reviewers" instrument were used to measure the quality indicators that address good teaching and learning practices. The authors outline the steps in the process of developing and managing such an online graduate distance learning program.

While motor and cortical neurons are affected in C9orf72 amyotrophic lateral sclerosis and frontotemporal dementia (ALS/FTD), it remains largely unknown if and how non-neuronal cells induce or exacerbate neuronal damage. We differentiated C9orf72 ALS/FTD patient-derived induced pluripotent stem cells into microglia (iPSC-MG) and examined their intrinsic phenotypes. Similar to iPSC motor neurons, C9orf72 ALS/FTD iPSC-MG mono-cultures form G4C2 repeat RNA foci, exhibit reduced C9orf72 protein levels, and generate dipeptide repeat proteins. Healthy control and C9orf72 ALS/FTD iPSC-MG equally express microglial specific genes and perform microglial functions, including inflammatory cytokine release and phagocytosis of extracellular cargos, such as synthetic amyloid beta peptides and healthy human brain synaptoneurosomes. RNA sequencing analysis revealed select transcriptional changes of genes associated with neuroinflammation or neurodegeneration in diseased microglia yet no significant differentially expressed microglial-enriched genes. Moderate molecular and functional differences were observed in C9orf72 iPSC-MG mono-cultures despite the presence of C9orf72 pathological features suggesting that a diseased microenvironment may be required to induce phenotypic changes in microglial cells and the associated neuronal dysfunction seen in C9orf72 ALS/FTD neurodegeneration.

Although wetlands contain a disproportionately high amount of earth’s total soil carbon, many regions are still poorly mapped and with unquantified carbon stocks. The tropical Andes contain a high concentration of wetlands consisting mostly of wet meadows and peatlands, yet their total organic carbon stocks are poorly quantified, as well as the carbon fraction that wet meadows store compared to peatlands. Therefore, our goal was to quantify how soil carbon stocks vary between wet meadows and peatlands for a previously mapped Andean region, Huascarán National Park, Peru. Our secondary goal was to test a rapid peat sampling protocol to facilitate field sampling in remote areas. We sampled soil to calculate carbon stocks of four wetland types: cushion peat, graminoid peat, cushion wet meadow, and graminoid wet meadow. Soil sampling was conducted by using a stratified randomized sampling scheme. Wet meadows were sampled to the mineral boundary using a gouge auger, and we used a combination of full peat cores and a rapid peat sampling procedure to estimate peat carbon stocks. In the lab, soils were processed for bulk density and carbon content, and total carbon stock of each core was calculated. We sampled 63 wet meadows and 42 peatlands. On a per hectare basis, carbon stocks varied strongly between peatlands (avg. 1092 MgC ha-1) and wet meadows (avg. 30 MgC ha-1). Overall, wetlands in Huascarán National Park contain 24.4 Tg of carbon with peatlands storing 97% of the total wetland carbon and wet meadows accounting for 3% of the wetland carbon in the park. In addition, our results show that rapid peat sampling can be an effective method for sampling carbon stocks in peatlands. These data are important for countries developing land use and climate change policies as well as providing a rapid assessment method for wetland carbon stock monitoring programs.

Summary: BRIDE OF DOUBLETIME (BDBT) interacts with the circadian kinase DOUBLETIME (DBT) and accumulates in eye foci during the dark of a light:dark cycle. BDBT foci are shown here to be broadly expressed in constant dark and low in constant light. Analysis of circadian photoreceptor cry and visual photoreceptor ninaE mutants showed that disappearance of eye BDBT foci requires both the CRYPTOCHROME and the RHODOPSIN-1 pathways. The arr1 and arr2 mutants, which affect rhodopsin quenching, eliminated BDBT foci under dark conditions. arr1 and arr2 mutants also caused increased nuclear PER protein. The changes in BDBT foci do not result from altered BDBT levels in the eye but from changes in its immunodetection. Knockdown of BDBT specifically in the eye produced constitutively nuclear PER and constitutively cytosolic DBT. The results show that BDBT is necessary for co-transport of DBT and PER into the nucleus and suggest that this process is regulated by a light-dependent mechanism.

The "National School Library Standards" stress the importance of the school library as "a third space for learning, a space between the classroom and home" (AASL 2018, 11). Over the past year and a half, there has been no guarantee that the physical school library will be accessible to provide this essential third space for learning. This article discusses ways a school library's third space can expand into cyberspace.

The authors present a new approach to show how interdisciplinary collaborations among a group of institutions can provide a unique opportunity for students to engage across the science-policy nexus using the framework of the Sustainable Development Goals and the United Nations Framework Convention on Climate Change. Through collaboration across seven higher education institutions in the United States and Australia, virtual student research teams worked together across disciplines such as economics, ecology, and other earth and social sciences to address research questions centered on sustainable development goals. The teams presented their findings in person to diplomats and delegates at the 2019 United Nations Conference of the Parties meeting in Madrid, which also had strong qualitative impacts on their perceptions of international science-policy interfaces.

Women in STEM are underrepresented and face challenges in balancing work and family. Therefore, mentoring is an important career intervention that focuses on individual's well-being and professional career. This study introduces a voluntary, flexible, context-sensitive and informal peer-based mentoring model. Twenty-six female STEM professors from Jordanian universities participated in the program for an academic year, self-identifying as mentors/mentees, creating a unique mentoring network across institutions. This case study uses multiple data sources to illustrate opportunities and challenges inherent in the model. Most participants found the program enriching, exciting and a challenging learning experience. Mentors reported increases in self-confidence and satisfaction derived from contributing to the academic community. Mentees emphasized their continuous learning and improved prioritisation skills. Both reflected on the importance of peer-mentoring for women in academia. The flexibility and organic growth possibility of the model is promising and holds important implications for policy makers and practitioners for future implementation.

The Wisconsin School Violence and Bullying Prevention Study, funded by the National Institutes of Justice (NIJ), was a two-year case-control study in 24 Wisconsin middle schools (11 experimental; 13 control) seeking to understand the impact of a comprehensive bullying prevention program on bullying victimization rates. Participating schools' bullying prevention programs were assessed at baseline and project-end using the Wisconsin Bullying Prevention Program Assessment Tool (BPPAT). This self-assessment tool, developed prior to the start of the research project, was developed by the Wisconsin Department of Public Instruction (DPI) and partners throughout Wisconsin. The BPPAT is an open-source 42-item assessment tool across 9 topic areas focused on policies and procedures with minimal financial and logistical burdens towards implementation. By design, it acknowledges wide variance across schools and districts for current practices and provides guidance, going forward, for program improvement. In the accompanying study, experimental schools were instructed to, with technical assistance, enhance their program by filling gaps identified through their completion of the BPPAT over two school years. A significant enhancement resulted among all schools, experimental and control, between 2015 and 2017 with a spill-over effect due to data collection requirements reducing programmatic differences between groups. Experimental schools reported significant declines in verified incidents of bullying with a non-significant decline among control schools. From this project, researchers determined that (1) schools are able to make program improvements in a short time period and (2) this concerted, and largely non-prescriptive, effort can have a positive and measurable impact on bullying victimization at this age group. Broader implications for the BPPAT and its use are preliminary and next steps are discussed and recommendations made.