Alien Registration- Bisson, Mary A. (Gardiner, Kennebec County)

https://digitalmaine.com/alien_docs/29105/thumbnail.jp

How Characean algae take up needed and excrete unwanted ions – An overview explaining how insights from electrophysiology are useful to understand the ecology of aquatic macrophytes

Characean algae have been a model plant for electrophysiology for many decades, due to the large size of the internodal cells and their robust recovery from invasive manipulation. The information gained from them has provided a template for understanding the electrophysiology of many plant groups. The relative ability to take up or export ions, including nutrients and toxins, can be part of the explanation as to why certain macrophytes occur preferably in nutrient-rich or oligotrophic habitats, why some macrophytes can grow in brackish water or only in freshwater, or why growth is limited to a particular range of pH. The electrical characteristics of the macrophyte’s cells play a determining factor in these transport properties, yet electrophysiological results are seldom cited in ecological publications, perhaps due to difficulties of communication between fields with different research approaches and terminology. We here present main electrophysiological findings on the transport of ions in and out of cells, in a way that is more accessible to ecologists. We examine the mechanism by which Characean algae generate the electrical voltage difference across their membrane, its effect on the transport of ions, and the mechanisms by which ions can be moved against the gradients that determine passive movements. Finally, we use the example of salinity tolerance to show what we learn about the evolution of salt tolerance in plants by using electrophysiological techniques.publishedVersio

An Operational Overview of the EXport Processes In the Ocean From RemoTe Sensing (EXPORTS) Northeast Pacific Field Deployment

The goal of the EXport Processes in the Ocean from RemoTe Sensing (EXPORTS) field campaign is to develop a predictive understanding of the export, fate, and carbon cycle impacts of global ocean net primary production. To accomplish this goal, observations of export flux pathways, plankton community composition, food web processes, and optical, physical, and biogeochemical (BGC) properties are needed over a range of ecosystem states. Here we introduce the first EXPORTS field deployment to Ocean Station Papa in the Northeast Pacific Ocean during summer of 2018, providing context for other papers in this special collection. The experiment was conducted with two ships: a Process Ship, focused on ecological rates, BGC fluxes, temporal changes in food web, and BGC and optical properties, that followed an instrumented Lagrangian float; and a Survey Ship that sampled BGC and optical properties in spatial patterns around the Process Ship. An array of autonomous underwater assets provided measurements over a range of spatial and temporal scales, and partnering programs and remote sensing observations provided additional observational context. The oceanographic setting was typical of late-summer conditions at Ocean Station Papa: a shallow mixed layer, strong vertical and weak horizontal gradients in hydrographic properties, sluggish sub-inertial currents, elevated macronutrient concentrations and low phytoplankton abundances. Although nutrient concentrations were consistent with previous observations, mixed layer chlorophyll was lower than typically observed, resulting in a deeper euphotic zone. Analyses of surface layer temperature and salinity found three distinct surface water types, allowing for diagnosis of whether observed changes were spatial or temporal. The 2018 EXPORTS field deployment is among the most comprehensive biological pump studies ever conducted. A second deployment to the North Atlantic Ocean occurred in spring 2021, which will be followed by focused work on data synthesis and modeling using the entire EXPORTS data set

Patient Retention and Adherence to Antiretrovirals in a Large Antiretroviral Therapy Program in Nigeria: A Longitudinal Analysis for Risk Factors

Substantial resources and patient commitment are required to successfully scale-up antiretroviral therapy (ART) and provide appropriate HIV management in resource-limited settings. We used pharmacy refill records to evaluate risk factors for loss to follow-up (LTFU) and non-adherence to ART in a large treatment cohort in Nigeria.We reviewed clinic records of adult patients initiating ART between March 2005 and July 2006 at five health facilities. Patients were classified as LTFU if they did not return >60 days from their expected visit. Pharmacy refill rates were calculated and used to assess non-adherence. We identified risk factors associated with LTFU and non-adherence using Cox and Generalized Estimating Equation (GEE) regressions, respectively. Of 5,760 patients initiating ART, 26% were LTFU. Female gender (p < 0.001), post-secondary education (p = 0.03), and initiating treatment with zidovudine-containing (p = 0.004) or tenofovir-containing (p = 0.05) regimens were associated with decreased risk of LTFU, while patients with only primary education (p = 0.02) and those with baseline CD4 counts (cell/ml(3)) >350 and <100 were at a higher risk of LTFU compared to patients with baseline CD4 counts of 100-200. The adjusted GEE analysis showed that patients aged <35 years (p = 0.005), who traveled for >2 hours to the clinic (p = 0.03), had total ART duration of >6 months (p<0.001), and CD4 counts >200 at ART initiation were at a higher risk of non-adherence. Patients who disclosed their HIV status to spouse/family (p = 0.01) and were treated with tenofovir-containing regimens (p < or = 0.001) were more likely to be adherent.These findings formed the basis for implementing multiple pre-treatment visit preparation that promote disclosure and active community outreaching to support retention and adherence. Expansion of treatment access points of care to communities to diminish travel time may have a positive impact on adherence

Alien Registration- Bisson, Mary A. (Gardiner, Kennebec County)

https://digitalmaine.com/alien_docs/29105/thumbnail.jp