Epidemiologic Approaches to Understanding Gonorrhea Transmission Dynamics and the Development of Antimicrobial Resistance

Globally, the incidence of infection caused by Neisseria gonorrhoeae is the second highest among the bacterial sexually transmitted infections. In Canada, declining rates during the 1990s suggested progress toward curbing gonorrhea; however, those have been increasing since 1999, with rates in Saskatchewan among the highest in the country. Infection can cause serious complications in men and women, and reported resistance to third-generation cephalosporins could lead to potentially untreatable infections. Increased understanding of gonorrhea transmission dynamics, sexual networks, and predictors of antimicrobial resistance development is needed to inform the development of improved approaches to prevention and treatment. The research presented herein draws upon data from Shanghai, China, and Saskatchewan, Canada, to compare and contrast varying epidemiologic approaches to enhancing understanding of gonorrhea in the two settings. Using traditional statistical approaches, multi-level statistical modeling, social network analysis, and dynamic simulation modeling, questions related to sexual behavior, partner presentation, and antimicrobial resistance development are explored. Each technique is evaluated for its potential contribution to overall understanding of the issues related to the ongoing gonorrhea epidemic, globally, and in Saskatchewan. The relative strengths and limitations of the application of the analytical approaches in the different settings are described. Socio-demographic characteristics provided useful indicators of antimicrobial resistant infection among patients with gonorrhea from Shanghai. Further, socio-demographic characteristics were also useful for predicting presentation of a partner for testing and treatment and the use of condoms during intercourse, among this study population. In Saskatchewan, socio-demographic characteristics were useful in predicting coinfection with gonorrhea and chlamydia at the time of diagnosis as well as repeat infection with gonorrhea. Social network analysis of the Saskatchewan dataset provided little additional understanding of the gonorrhea epidemic in the province. This result was largely related to how STI data are collected and stored in the province. The utility of dynamic simulation modeling to investigate the potential impact of antimicrobial resistance in Saskatchewan was also limited due to the same data constraints. However, the insight gained from the model building process and findings from the working model did offer a starting point for conversations around the best ways to postpone the development of antimicrobial resistance in N. gonorrhoeae in Saskatchewan, as well as contribute additional information about how the ways in which STI data are collected and stored in the province considerably restrict the applicability of otherwise powerful epidemiologic tools. With persistently high rates of disease transmission, and the threat of untreatable infections due to antimicrobial resistance, N. gonorrhoeae remains a substantial public health threat locally and globally. The research presented herein describes various approaches to understanding and controlling this disease, applied in contrasting settings. There are a wide variety of elements that should be considered when choosing the appropriate tool(s) to address gonorrhea in a given population; there is no “one size fits all” solution. The local epidemiology of disease, cultural and behavioural norms, the characteristics of the notifiable disease reporting and information systems, and the availability of suitable data all affect the relative strengths and weaknesses of the available analytic methods and disease control approaches

Project apollo. ship-shore communications using radio satellite relay

Requirements for antennas, radio and terminal equipment aboard Apollo communication and tracking ships to communicate with land stations by satellite rela

Infant and toddler care

The purpose of this review of recent research is to identify the quality of care that infants and toddlers are receiving in both home-based and center-based care settings. The review will also identify how infant and toddler caregivers perceive their work, and ways that professional development opportunities can positively impact the quality of care for infant and toddlers. The conclusion of this literature review includes recommendations for future action and education policies based on the research reviewed

Investigating the impact of poverty on colonization and infection with drug-resistant organisms in humans: a systematic review

Background Poverty increases the risk of contracting infectious diseases and therefore exposure to antibiotics. Yet there is lacking evidence on the relationship between income and non-income dimensions of poverty and antimicrobial resistance. Investigating such relationship would strengthen antimicrobial stewardship interventions. Methods A systematic review was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed, Ovid, MEDLINE, EMBASE, Scopus, CINAHL, PsychINFO, EBSCO, HMIC, and Web of Science databases were searched in October 2016. Prospective and retrospective studies reporting on income or non-income dimensions of poverty and their influence on colonisation or infection with antimicrobial-resistant organisms were retrieved. Study quality was assessed with the Integrated quality criteria for review of multiple study designs (ICROMS) tool. Results Nineteen articles were reviewed. Crowding and homelessness were associated with antimicrobial resistance in community and hospital patients. In high-income countries, low income was associated with Streptococcus pneumoniae and Acinetobacter baumannii resistance and a seven-fold higher infection rate. In low-income countries the findings on this relation were contradictory. Lack of education was linked to resistant S. pneumoniae and Escherichia coli. Two papers explored the relation between water and sanitation and antimicrobial resistance in low-income settings. Conclusions Despite methodological limitations, the results suggest that addressing social determinants of poverty worldwide remains a crucial yet neglected step towards preventing antimicrobial resistance

Quantifying the effects of daily light integral or photoperiod on maize tassel morphology across developmental stages

ABSTRACT Maize (Zea mays L.) is an important agronomic crop throughout the world. Maize seed production and trait introgression is performed in both field and greenhouse settings (which allow for continual production seasons). The winter months within the greenhouses produce maize tassels with increased barren tassel branches (suppressed anther production) and the hypothesis is that the most limiting factor is daily light integral (DLI). Growing maize year-round in temperate regions, such as the northern part of the United States, requires the use-of greenhouse production. The low light intensities of these regions in the winter months creates a need for supplemental lighting for crops such as maize, that are high-light species. Utilizing a controlled environment, such as a greenhouse, also allows for control over the environmental factors such as temperature, light, moisture, gases and nutrients. Temperature, moisture, and nutrients can be supplied as needed, and maize does not require CO2 regulation because it is a C4 plant. The last factor, light, is most limited on cloudy or winter days, therefore plants require supplemental lighting to provide the additional light needed to produce a high-quality maize tassel. Our objectives were to investigate how the maize plant grows and develops in response to lower DLI levels. After determining the impact that DLI has on maize quality we aimed to quantify the threshold of low DLI needed before tassel barrenness increases, and to explore opportunities to prevent the low DLI stress from occurring. This thesis describes research that was carried out to achieve these objectives and provides a discussion on the implications of these results.</p