Estimating the costs and benefits of providing free public transit passes to students in Los Angeles County: lessons learned in applying a health lens to decision-making.

In spite of increased focus by public health to engage and work with non-health sector partners to improve the health of the general as well as special populations, only a paucity of studies have described and disseminated emerging lessons and promising practices that can be used to undertake this work. This article describes the process used to conduct a Health Impact Assessment of a proposal to provide free public transportation passes to students in Los Angeles County. This illustrative case example describes opportunities and challenges encountered in working with an array of cross-sector partners and highlights four important lessons learned: (1) the benefits and challenges associated with broad conceptualization of public issues; (2) the need for more comprehensive, longitudinal data systems and dynamic simulation models to inform decision-making; (3) the importance of having a comprehensive policy assessment strategy that considers health impacts as well as costs and feasibility; and (4) the need for additional efforts to delineate the interconnectivity between health and other agency priorities. As public health advances cross-sector work in the community, further development of these priorities will help advance meaningful collaboration among all partners

California TRV-based VIGS vectors mediate gene silencing at elevated temperatures but with greater growth stunting

BACKGROUND: Tobacco rattle virus (TRV) based virus-induced gene silencing (VIGS), a widely used functional genomics tool, requires growth temperatures typically lower than those of the plant’s native environment. Enabling VIGS under native conditions in the field according to applicable safety regulations could be a revolutionary advance for ecological research. RESULTS: Here, we report the development of an enhanced thermal tolerant VIGS vector system based on a TRV California isolate. cDNA clones representing the whole viral genome were sequenced and used to construct separate binary plant transformation vectors for functional elements of RNA1 (6765 nt) and RNA2 (3682 nt). VIGS of target genes was induced by transient transformation of the host plant with both vectors or by treating the host plant with sap from already VIGS induced plants. In Nicotiana attenuata the silencing efficiency of the PDS (phytoene desaturase) gene was 90% at 28 °C and 78% at 30 °C. Silencing at these temperatures was more prominent and durable than silencing induced by the widely used TRV PpK20-based pBINTRA6/pTV00 system, but was associated with a viral phenotype. Differences in the suppressor protein and RNA dependent RNA polymerase sequences between the TRV California isolate and PpK20 may be the reason for their different thermal tolerance. CONCLUSIONS: The new TRV California-based VIGS vectors induce gene silencing in Nicotiana attenuata at higher temperatures than the existing pBINTRA6/pTV00 vector system, but cause greater growth defects. The new vector system opens up an avenue to study genes functions in planta under field conditions. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12870-021-03324-8

Research and Design of a Two-Stage Supersonic Rocket

This report documents the entire design process for a two-stage vertical launch vehicle and highlights the team’s research, design work, testing, and construction of the launch vehicle. Every major system of the launch vehicle, including motors, electronics systems, interior and exterior structures, and recovery, will be individually analyzed and assessed during the design process. The launch vehicle will compete at the 2020 Spaceport America Cup in Las Cruces, New Mexico. Undergoing this project will allow the team members to further develop the skills learned throughout the Mechanical Engineering curriculum and Aerospace Systems Engineering curriculum at the University of Akron. Additionally, the findings of this report will provide a basis for future innovation within the University of Akron’s Akronauts Rocket Design Team

Increasing the reliability of fully automated surveillance for central line–associated bloodstream infections

OBJECTIVETo increase reliability of the algorithm used in our fully automated electronic surveillance system by adding rules to better identify bloodstream infections secondary to other hospital-acquired infections.METHODSIntensive care unit (ICU) patients with positive blood cultures were reviewed. Central line–associated bloodstream infection (CLABSI) determinations were based on 2 sources: routine surveillance by infection preventionists, and fully automated surveillance. Discrepancies between the 2 sources were evaluated to determine root causes. Secondary infection sites were identified in most discrepant cases. New rules to identify secondary sites were added to the algorithm and applied to this ICU population and a non-ICU population. Sensitivity, specificity, predictive values, and kappa were calculated for the new models.RESULTSOf 643 positive ICU blood cultures reviewed, 68 (10.6%) were identified as central line–associated bloodstream infections by fully automated electronic surveillance, whereas 38 (5.9%) were confirmed by routine surveillance. New rules were tested to identify organisms as central line–associated bloodstream infections if they did not meet one, or a combination of, the following: (I) matching organisms (by genus and species) cultured from any other site; (II) any organisms cultured from sterile site; (III) any organisms cultured from skin/wound; (IV) any organisms cultured from respiratory tract. The best-fit model included new rules I and II when applied to positive blood cultures in an ICU population. However, they didn’t improve performance of the algorithm when applied to positive blood cultures in a non-ICU population.CONCLUSIONElectronic surveillance system algorithms may need adjustment for specific populations.Infect. Control Hosp. Epidemiol. 2015;36(12):1396–1400</jats:sec

Microarrays in ecological research: A case study of a cDNA microarray for plant-herbivore interactions

BACKGROUND: Microarray technology allows researchers to simultaneously monitor changes in the expression ratios (ERs) of hundreds of genes and has thereby revolutionized most of biology. Although this technique has the potential of elucidating early stages in an organism's phenotypic response to complex ecological interactions, to date, it has not been fully incorporated into ecological research. This is partially due to a lack of simple procedures of handling and analyzing the expression ratio (ER) data produced from microarrays. RESULTS: We describe an analysis of the sources of variation in ERs from 73 hybridized cDNA microarrays, each with 234 herbivory-elicited genes from the model ecological expression system, Nicotiana attenuata, using procedures that are commonly used in ecologic research. Each gene is represented by two independently labeled PCR products and each product was arrayed in quadruplicate. We present a robust method of normalizing and analyzing ERs based on arbitrary thresholds and statistical criteria, and characterize a "norm of reaction" of ERs for 6 genes (4 of known function, 2 of unknown) with different ERs as determined across all analyzed arrays to provide a biologically-informed alternative to the use of arbitrary expression ratios in determining significance of expression. These gene-specific ERs and their variance (gene CV) were used to calculate array-based variances (array CV), which, in turn, were used to study the effects of array age, probe cDNA quantity and quality, and quality of spotted PCR products as estimates of technical variation. Cluster analysis and a Principal Component Analysis (PCA) were used to reveal associations among the transcriptional "imprints" of arrays hybridized with cDNA probes derived from mRNA from N. attenuata plants variously elicited and attacked by different herbivore species and from three congeners: N. quadrivalis, N. longiflora and N. clevelandii. Additionally, the PCA revealed the contribution of individual gene ERs to the associations among arrays. CONCLUSIONS: While the costs of 'boutique' array fabrication are rapidly declining, familiar methods for the analysis of the data they create are still missing. The case history illustrated here demonstrates the ease with which this powerful technology can be adapted to ecological research

Two-fold differences are the detection limit for determining transgene copy numbers in plants by real-time PCR

BACKGROUND: After transformation, plants that are homozygous and contain one copy of the transgene are typically selected for further study. If real-time PCR is to be used to determine copy number and zygosity, it must be able to distinguish hemizygous from homozygous and one-copy from two-copy plants. That is, it must be able to detect two-fold differences. RESULTS: When transgenic Nicotiana attenuata plants which had been previously determined by Southern analysis to contain one or two copies of the transgene, were analyzed by real-time PCR (2(-ΔΔCt )method), the method failed to confirm the results from the Southern analysis. In a second data set we analyzed offspring of a hemizygous one-copy plant, which were expected to segregate into three groups of offspring in a 1:2:1 ratio: no transgene, hemizygous, homozygous. Because it was not possible to distinguish homozygous from hemizygous plants with real-time PCR, we could not verify this segregation ratio. CONCLUSIONS: Detection of two-fold differences by real-time PCR is essential if this procedure is to be used for the characterization of transgenic plants. However, given the high variability between replicates, a detection of two-fold differences is in many cases not possible; in such cases Southern analysis is the more reliable procedure

Youths\u27 Perspectives on the Reasons Underlying School Truancy and Opportunities to Improve School Attendance

School truancy is common in the United States; however, youths’ perspectives on the underlying reasons for and the best ways to curtail this phenomenon are lacking. This project sought to better understand what factors contribute to youths’ decisions to skip classes or ditch full days of school over time and to solicit youths’ recommendations on how to reduce truancy and improve system functioning. We used a community partnered qualitative descriptive approach to conduct in-depth interviews with 39 youths with a history of truancy from South and East Los Angeles. Youths’ experiences and recommendations illustrate the multiple factors that influence school truancy and suggest potential leverage points for reducing truancy, including modifications to the school environment to increase student engagement; a more effective school response to address truancy; and further involvement and engagement of parents. Researchers, policy makers, and school practitioners can use results to help inform efforts to address school truancy

An unbiased approach elucidates variation in (S)-(+)-linalool, a context-specific mediator of a tri-trophic interaction in wild tobacco

Plant volatile organic compounds (VOCs) mediate many interactions, and the function of common VOCs is especially likely to depend on ecological context. We used a genetic mapping population of wild tobacco, Nicotiana attenuata, originating from a cross of 2 natural accessions from Arizona and Utah, separated by the Grand Canyon, to dissect genetic variation controlling VOCs. Herbivory-induced leaf terpenoid emissions varied substantially, while green leaf volatile emissions were similar. In a field experiment, only emissions of linalool, a common VOC, correlated significantly with predation of the herbivore Manduca sexta by native predators. Using quantitative trait locus mapping and genome mining,we identified an (S)-(+)-linalool synthase (NaLIS). Genome resequencing, gene cloning, and activity assays revealed that the presence/absence of a 766-bp sequence in NaLIS underlies the variation of linalool emissions in 26 natural accessions. We manipulated linalool emissions and composition by ectopically expressing linalool synthases for both enantiomers, (S)-(+)- and (R)-(−)-linalool, reported to oppositely affect M. sexta oviposition, in the Arizona and Utah accessions.We used these lines to test ovipositingmoths in increasingly complex environments. The enantiomers had opposite effects on oviposition preference, but themagnitude of the effect depended strongly both on plant genetic background, and complexity of the bioassay environment. Our study reveals that the emission of linalool, a common VOC, differs by orders-of-magnitude among geographically interspersed conspecific plants due to allelic variation in a linalool synthase, and that the response of a specialist herbivore to linalool depends on enantiomer, plant genotype, and environmental complexity