Public Health Panel

8 graduate student/recent graduate presentations on varying topics related to public health. Moderated by Dr. Jessica Prodger. Reporting of panel done by current GHS students of the 2021 class. Abstracts can be found under Africa-Western Collaborations Day 2020 Abstracts . Presenters as follows: Roger Antabe et al., HIV Prevention Among Heterosexual Blackmen in Ontario: The Need to Revisit Provincial Policy Ayah Karra-Aly, Adaku Ohuruogu, Georgia Raithby, Jasandeep Sehra, The Power of Poop Ryan LaPenna et al., Using a One Health Approach to Address the Challenges Posed by Rabies to Animals and People in Rurals Areas in Victoria Falls, Zimbabwe Gurleen Saini, Anusheh Khan, Priscilla Matthews, Malaria Elimination Zhongtian (Eric) Shao et al., Effect of Physical Maturation and Sexual Debut on HIV Susceptibility in Adolescent Males in Rakai, Uganda Steven Trothen et al., Evaluation of Cytokine Profiles within the Endocervical Tract of HIV-1 Infected Females Jason Were et al., The Epidemiology of Overweight and Obesity in Ghana: Examination of Predictors and Risk Groups among Women of Childbearing Age Bianca Ziegler et al., Antenatal Care Utilization in the Fragile and Conflict-Affected Context of the Democratic Republic of Cong

SPATIAL AND TEMPORAL VARIABILITY OF SANDY BEACH SEDIMENT GRAIN SIZE AND SORTING

Beach grain size plays a major role in controlling beach slope and sediment transport rates and is a crucial criterion in selecting the appropriate fill material for beach nourishment. Yet, little is known about how and why beach grain size (and sorting) varies both spatially and temporally on high-energy sandy beaches. Therefore, in this PhD research project, the presence, magnitude and predictability of any spatio-temporal sediment variability was investigated on a number of contrasting high-energy (average significant wave height = 0.8 to 3.5 m), predominantly macrotidal (MSR = 3.1 – 6.2 m), sandy (0.26 – 0.64 mm) beach sites around the southwest peninsula of the United Kingdom (UK). The spatial extent of the data collected ranges from regional (one off snapshot of the sediment conditions on 53 beaches over 485 km of coastline) to local scales (repeated high-resolution samples from across the inter- and subtidal zone of a single high-energy sandy beach; Perranporth, UK). The temporal scales of the sampling ranges from tidal scale (~12 hours) up to monthly (long-term monitoring since 2008). A combination of traditional and modern field data collection methods has provided new insights into the sediment dynamics of sandy beaches. Surface and 0.25 m core sediment samples from the 53 beaches around the southwest UK and high-resolution digital measurements with longer 1 m sand cores from the intertidal zone, plus grab samples from the subtidal zone, at Perranporth, indicated the presence of three quasi-permanent spatial trends. On all sandy beaches, surface sediments became coarser (and better sorted) in the seaward direction across the intertidal zone. Peak sediment sizes were observed on the lower beach around mean low water springs, which were an average 19% coarser (and 8% better sorted) than sediments sampled on the upper intertidal beach. Sediment size (and sorting) also increased (improved) with distance down the sediment column over the top 0.25 m to 1 m. Peak sediment sizes at depth were an average 16% coarser (and 16% better sorted) than surface sediments. In the subtidal zone, surface sediments became finer and poorer sorted with increasing offshore distance. Minimum sediment size occurred on the subtidal bar crest and were an average 21% finer (and 51% poorer sorted) than the lower beach sediments and 5% finer (and 38% poorer sorted) than upper beach sediments. The coarsest sediments were usually the best sorted at all locations. The intertidal coarsening was deterministically linked to the location and amount of breaking wave-induced turbulence. The peak sediment sizes (and sorting) on the lower beach correlated with the location of peak wave dissipation (sediment size to amount of wave dissipation, r2 = 0.86) and the finer sediment sizes on the upper beach and bar were coincident with reduced amounts of wave dissipation in these regions. Long-term seasonal monitoring of the surface sediments at Perranporth indicated a background seasonality, where the winter months were an average 35% coarser and 22% better sorted than samples collected in summer. This seasonal pattern was punctuated by episodic storm events that promoted a significant coarsening (up to 112% in the extreme winter storms of 2014) of the surface sediments and significant beach erosion up to 175 m3/m. An empirical model forced by the degree of disequilibrium between an instantaneous and antecedent (weighted average) wave steepness time series was able to capture up to 86% of the sediment grain size and sorting variability, incorporating both the seasonal and storm driven change. The same model, applied to daily observations of sediment size and sorting changes was able to explain 72% of the variability. A conceptual model is proposed that extends the cross-shore sediment transport shape functions to include the various sediment (size and sorting) responses alongside the morphodynamic evolution during persistently high and low wave steepness conditions. Under high steepness waves, the finer material is preferentially removed from the lower intertidal beach, leaving behind coasrer sediments. This fine material is transported to the subtidal bar, which becomes finer (and more poorly sorted) inversely with the coarsening (and improved sorting) of the intertidal zone sediments. Under low steepness waves, this fine material is returned from the bar to the intertidal beach. This work provides a detailed, quantitative insight into the magnitude of sediment grain size and sorting changes exhibited by sandy beaches on a number of spatial and temporal scales. Several consistent trends were observed on a range of sandy beaches despite their different environmental conditions and geological histories. This improved understanding of sediment grain size and sorting changes on beaches will hopefully aid future research efforts and ensure that this fundamental aspect of coastal science is not overlooked or oversimplified

Sustaining warm and inclusive transitions across the early years: insights from the START project

Le buone transizioni positive tra casa, ECEC e istruzione scolastica obbligatoria (CSE) sono fondamentali per promuovere lo sviluppo ed il successo scolastico dei bambini, in particolare nel caso di bambini provenienti da background migrante. Tuttavia, a causa di pratiche istituzionali obsolete per quanto radicate e alla mancanza di aggiornamento rispetto a questo tema da parte dei diversi gruppi di professionisti coinvolti, il modo in cui le transizioni sono gestite tende a favorire involontariamente i bambini provenienti da contesti più avvantaggiati, le cui famiglie sanno come 'muoversi' nel sistema educativo, anche in situazioni di criticità. L'articolo presenta i risultati di uno studio transnazionale di azione-ricerca partecipativa (START) condotto in quattro paesi (Italia, Slovenia, Inghilterra, Belgio), discutendo di come un approccio inclusivo di gestione delle pratiche di continuità educativa e scolastica possa meglio rispondere alle esigenze dei bambini migranti e delle famiglie in modo olistico modo.Positive transitions across home, ECEC and compulsory school education (CSE) are critical in promoting children's development and educational achievement: this seems especially the case for children from migrant backgrounds. However, as a consequence of entrenched institutional practices and lack of ownership the issues by the different groups of professionals involved, the way transitions are managed tends to unintentionally favour children from more advantaged backgrounds, whose families know how to navigate the educational system, including its flaws. The article presents the findings from a transnational participatory action-research study (START) carried out in four countries (Italy, Slovenia, England, Belgium), discussing how an inclusive transition approach can better address the needs of migrant children and families in a holistic way

Penile anaerobic dysbiosis as a risk factor for HIV infection

Sexual transmission of HIV requires exposure to the virus and infection of activated mucosal immune cells, specifically CD4+ T cells or dendritic cells. The foreskin is a major site of viral entry in heterosexual transmission of HIV. Although the probability of acquiring HIV from a sexual encounter is low, the risk varies even after adjusting for known HIV risk factors. The genital microbiome may account for some of the variability in risk by interacting with the host immune system to trigger inflammatory responses that mediate the infection of mucosal immune cells. We conducted a case-control study of uncircumcised participants nested within a randomized-controlled trial of male circumcision in Rakai, Uganda. Using penile (coronal sulcus) swabs collected by study personnel at trial enrollment, we characterized the penile microbiome by sequencing and real-time PCR and cytokine levels by electrochemiluminescence assays. The absolute abundances of penile anaerobes at enrollment were associated with later risk of HIV seroconversion, with a 10-fold increase in Prevotella, Dialister, Finegoldia, and Peptoniphilus increasing the odds of HIV acquisition by 54 to 63%, after controlling for other known HIV risk factors. Increased abundances of anaerobic bacteria were also correlated with increased cytokines, including interleukin-8, which can trigger an inflammatory response that recruits susceptible immune cells, suggesting a mechanism underlying the increased risk. These same anaerobic genera can be shared between heterosexual partners and are associated with increased HIV acquisition in women, pointing to anaerobic dysbiosis in the genital microbiome and an accompanying inflammatory response as a novel, independent, and transmissible risk factor for HIV infection. IMPORTANCE We found that uncircumcised men who became infected by HIV during a 2-year clinical trial had higher levels of penile anaerobes than uncircumcised men who remained HIV negative. We also found that having higher levels of penile anaerobes was also associated with higher production of immune factors that recruit HIV target cells to the foreskin, suggesting that anaerobes may modify HIV risk by triggering inflammation. These anaerobes are known to be shared by heterosexual partners and are associated with HIV risk in women. Therefore, penile anaerobes may be a sexually transmissible risk factor for HIV, and modifying the penile microbiome could potentially reduce HIV acquisition in both men and women

Addressing an HIV cure in LMIC

HIV-1 persists in infected individuals despite years of antiretroviral therapy (ART), due to the formation of a stable and long-lived latent viral reservoir. Early ART can reduce the latent reservoir and is associated with post-treatment control in people living with HIV (PLWH). However, even in post-treatment controllers, ART cessation after a period of time inevitably results in rebound of plasma viraemia, thus lifelong treatment for viral suppression is indicated. Due to the difficulties of sustained life-long treatment in the millions of PLWH worldwide, a cure is undeniably necessary. This requires an in-depth understanding of reservoir formation and dynamics. Differences exist in treatment guidelines and accessibility to treatment as well as social stigma between low- and-middle income countries (LMICs) and high-income countries. In addition, demographic differences exist in PLWH from different geographical regions such as infecting viral subtype and host genetics, which can contribute to differences in the viral reservoir between different populations. Here, we review topics relevant to HIV-1 cure research in LMICs, with a focus on sub-Saharan Africa, the region of the world bearing the greatest burden of HIV-1. We present a summary of ART in LMICs, highlighting challenges that may be experienced in implementing a HIV-1 cure therapeutic. Furthermore, we discuss current research on the HIV-1 latent reservoir in different populations, highlighting research in LMIC and gaps in the research that may facilitate a global cure. Finally, we discuss current experimental cure strategies in the context of their potential application in LMICs