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The extracytoplasmic functioning sigma factor σE is known to play an essential role for Salmonella enterica serovar Typhimurium to survive and proliferate in macrophages and mice. However, its regulatory network is not well characterized, especially during infection. Here we used microarray to identify genes regulated by σE in Salmonella grown in three conditions: a nutrient-rich condition and two others that mimic early and late intracellular infection. We found that in each condition σE regulated different sets of genes, and notably, several global regulators. When comparing nutrient-rich and infection-like conditions, large changes were observed in the expression of genes involved in Salmonella pathogenesis island (SPI)-1 type-three secretion system (TTSS), SPI-2 TTSS, protein synthesis, and stress responses. In total, the expression of 58% of Salmonella genes was affected by σE in at least one of the three conditions. An important finding is that σE up-regulates SPI-2 genes, which are essential for Salmonella intracellular survival, by up-regulating SPI-2 activator ssrB expression at the early stage of infection and down-regulating SPI-2 repressor hns expression at a later stage. Moreover, σE is capable of countering the silencing of H-NS, releasing the expression of SPI-2 genes. This connection between E and SPI-2 genes, combined with the global regulatory effect of σE, may account for the lethality of rpoE-deficient Salmonella in murine infection.

The alternative sigma factor σE functions to maintain bacterial homeostasis and membrane integrity in response to extracytoplasmic stress by regulating thousands of genes both directly and indirectly. The transcriptional regulatory network governed by σE in Salmonella and E. coli has been examined using microarray, however a genome-wide analysis of σE-binding sites in Salmonella has not yet been reported. We infected macrophages with Salmonella Typhimurium over a select time course. Using chromatin immunoprecipitation followed by high-throughput DNA sequencing (ChIP-seq), 31 σE-binding sites were identified. Seventeen sites were new, which included outer membrane proteins, a quorum-sensing protein, a cell division factor, and a signal transduction modulator. The consensus sequence identified for σE in vivo binding was similar to the one previously reported, except for a conserved G and A between the -35 and -10 regions. One third of the σE-binding sites did not contain the consensus sequence, suggesting there may be alternative mechanisms by which σE modulates transcription. By dissecting direct and indirect modes of σE-mediated regulation, we found that σE activates gene expression through recognition of both canonical and reversed consensus sequence. New σE regulated genes (greA, luxS, ompA and ompX) are shown to be involved in heat shock and oxidative stress responses.

Sarcoptic mange poses a serious conservation threat to endangered San Joaquin kit foxes (Vulpes macrotis mutica). After first appearing in Bakersfield, California in spring 2013, mange reduced the kit fox population approximately 50% until the epidemic ended with minimally detectable endemic cases after 2020. Mange is lethal and thus, with such a high force of infection and lack of immunity, it remains unclear why the epidemic did not burn itself out rapidly and how it persisted so long. Here we explored spatio-temporal patterns of the epidemic, analyzed historical movement data, and created a compartment metapopulation model (named "metaseir") to evaluate whether movement of foxes among patches and spatial heterogeneity would reproduce the eight years epidemic with 50% population reduction observed in Bakersfield. Our main findings from metaseir were that: 1) a simple metapopulation model can capture the Bakersfield-like disease epidemic dynamics even when there is no environmental reservoir or external spillover host, 2) the most impactful parameter on persistence and magnitude of the epidemic is the projection, β/αβ (transmission over decay rate of transmission over space), 3) heterogeneity in patch carrying capacities changes the critical value of the projection needed to achieve an epidemic but makes little difference to epidemic persistence time, and 4) the epidemic is relatively insensitive to birth rates and density vs. frequency-dependent transmission. Our model can help guide management and assessment of metapopulation viability of this vulpid subspecies, while the exploratory data analysis and model will also be valuable to understand mange in other, particularly den-occupying, species.

A cost-effective and efficacious influenza vaccine for use in commercial poultry farms would help protect against avian influenza outbreaks. Current influenza vaccines for poultry are expensive and subtype specific, and therefore there is an urgent need to develop a universal avian influenza vaccine. We have constructed a live bacterial vaccine against avian influenza by expressing a conserved peptide from the ectodomain of M2 antigen (M2e) on the surface of Lactococcus lactis (LL). Chickens were vaccinated intranasally with the lactococcal vaccine (LL-M2e) or subcutaneously with keyhole-limpet-hemocyanin conjugated M2e (KLH-M2e). Vaccinated and nonvaccinated birds were challenged with high pathogenic avian influenza virus A subtype H5N2. Birds vaccinated with LL-M2e or KLH-M2e had median survival times of 5.5 and 6.0 days, respectively, which were significantly longer than non-vaccinated birds (3.5 days). Birds vaccinated subcutaneously with KLH-M2e had a lower mean viral burden than either of the other two groups. However, there was a significant correlation between the time of survival and M2e-specific serum IgG. The results of these trials show that birds in both vaccinated groups had significantly (P

Strategic planning is the deliberative, disciplined effort to produce decisions and actions that shape and guide what an organization is, what it does, and why. [State] Cooperative Extension invested considerable time and effort in conducting a statewide process to engage internal and external stakeholders and nonusers. The strategic planning steering committee balanced negotiations in defining the process, determining who should be involved, and how to develop goals. The semi-structured interviews with the steering committee members, generated three themes: effectiveness of the team enhanced results; context and process can inhibit stakeholder participation, the steering committee needs a commitment to diverse voices.

Extension administrators discussed the competencies and characteristics of Extension professionals as they explored how Extension will need adapt to changing clientele, both in who they are and how they want to receive information. Extension education curriculum is not fully preparing future Extension employees in all required competencies, falling short on use of technology, diversity and pluralism, volunteer development, marketing, and public relations, risk management, and the community development process. Additionally, the Extension educator workforce development pipeline is not preparing a demographically representative population, leaving state administrators struggling to hire prepared professionals, especially those with in-culture competency (e.g., racial and ethnic minority and urban).

Academic resilience captures academic success despite adversity and thus is an important concept for promoting equity within education. However, our understanding of how and why rates of academic resilience differ between contexts is currently limited by variation in the ways that the construct has been operationalised in quantitative research. Similarly, comparing the strength of protective factors that promote academic resilience is hindered by differing approaches to the measurement of academic resilience. This methodological variation has complicated attempts to reconcile disparate findings about academic resilience. The current study applied six commonly used operationalisations of academic resilience that combined different thresholds of high risk and high achievement, to three international large-scale assessments, to explore how these different operationalisations impacted the findings produced. The context of Aotearoa New Zealand was chosen as a case study to further academic resilience research within this context and investigate how academic resilience manifests in an education system with relatively high levels of average achievement alongside low levels of educational equity. Within international large-scale assessment datasets, prevalence rates differed markedly across subject areas, grade levels, and collection cycles, as a function of the measure of academic resilience employed, while the strength of protective factors was more consistent. Thresholds that were norm-referenced produced more consistent findings across the different datasets compared to thresholds that were criterion-referenced. High levels of missing data prevented the analysis of some datasets, and differences in the way that key constructs were measured undermined the comparability of findings across international large-scale assessments. The findings emphasise the strengths and limitations of utilising international large-scale assessment data for the study of academic resilience, particularly within the Aotearoa New Zealand context. Furthermore, the study highlights that researchers' methodological decisions have important impacts on the conclusions drawn about academic resilience.