Developmental Reaction Norms for Water Stressed Seedlings of Succulent Cacti

Succulent cacti are remarkable plants with capabilities to withstand long periods of drought. However, their adult success is contingent on the early seedling stages, when plants are highly susceptible to the environment. To better understand their early coping strategies in a challenging environment, two developmental aspects (anatomy and morphology) in Polaskia chichipe and Echinocactus platyacanthus were studied in the context of developmental reaction norms under drought conditions. The morphology was evaluated using landmark based morphometrics and Principal Component Analysis, which gave three main trends of the variation in each species. The anatomy was quantified as number and area of xylem vessels. The quantitative relationship between morphology and anatomy in early stages of development, as a response to drought was revealed in these two species. Qualitatively, collapsible cells and collapsible parenchyma tissue were observed in seedlings of both species, more often in those subjected to water stress. These tissues were located inside the epidermis, resembling a web of collapsible-cell groups surrounding turgid cells, vascular bundles, and spanned across the pith. Occasionally the groups formed a continuum stretching from the epidermis towards the vasculature. Integrating the morphology and the anatomy in a developmental context as a response to environmental conditions provides a better understanding of the organism's dynamics, adaptation, and plasticity

Seed germination of Trichocereus terscheckii (Cactaceae): Light, temperature and gibberellic acid effects

In this paper, we evaluated the effect of light and temperature and addition of gibberellic acid (GA(3)) in the germination of seeds of Trichocerelis terscheckii in order to provide information about Germination requirements which could be use for conservation studies. The germination response within a temperature gradient was evaluated for seeds arising from two populations: La Pedrera and Cuesta del Obispo (Salta, Argentina). Seeds of T terscheckii germinated within a range from 15 to 35 degrees C. Maximum germination percentages were found under white light and no germination was recorded in darkness. GA(3) at any concentration promoted germination either in white light or darkness neither at a constant temperature nor at an alternating one. (c) 2006 Elsevier Ltd. All rights reserved

Lessons from Two Latino Communities Working with Academic Partners to Increase Access to COVID-19 Testing.

ObjectiveWe sought to examine the experiences of community partners in a community-academic partnership to promote COVID-19 testing in two majority Latino communities.MethodsWe conducted semistructured, in-depth interviews in English and Spanish with community-based organization leaders and community health workers/promotoras (n = 10) from June to July 2021. Interviews focused on identifying partner roles in planning and testing implementation and evaluating communication among partners. Interviews were transcribed and analyzed in ATLAS.ti version 8.4.5. Analyses involved deductive and inductive approaches to identify key themes.ResultsParticipants described both strengths and challenges to the collaborative approach within each of three core themes: building relationships in the time of COVID-19; uplifting existing community leadership; and commitment of the academic partners and community-based organizations to conduct partnership activities in Spanish.ConclusionCommunity-academic partnerships that invest in strong relationships, community leadership, and a commitment to the community's preferred language offer a promising approach to addressing COVID-19 testing barriers. Findings provide direction for future research on how community members and academic partners can come together to inform strategies to continue addressing the COVID-19 pandemic

Reproducibility and implementation of a rapid, community-based COVID-19 "test and respond" model in low-income, majority-Latino communities in Northern California.

ObjectiveTo evaluate implementation of a community-engaged approach to scale up COVID-19 mass testing in low-income, majority-Latino communities.MethodsIn January 2021, we formed a community-academic "Latino COVID-19 Collaborative" with residents, leaders, and community-based organizations (CBOs) from majority-Latinx, low-income communities in three California counties (Marin/Merced/San Francisco). The collaborative met monthly to discuss barriers/facilitators for COVID-19 testing, and plan mass testing events informed by San Francisco's Unidos en Salud "test and respond" model, offering community-based COVID-19 testing and post-test support in two US-census tracts: Canal (Marin) and Planada (Merced). We evaluated implementation using the RE-AIM framework. To further assess testing barriers, we surveyed a random sample of residents who did not attend the events.ResultsFifty-five residents and CBO staff participated in the Latino collaborative. Leading facilitators identified to increase testing were extended hours of community-based testing and financial support during isolation. In March-April 2021, 1,217 people attended mass-testing events over 13 days: COVID-19 positivity was 3% and 1% in Canal and Planada, respectively. The RE-AIM evaluation found: census tract testing coverage of 4.2% and 6.3%, respectively; 90% of event attendees were Latino, 89% had household income ConclusionCommunity-engaged mass "test and respond" events offer a reproducible approach to rapidly increase COVID-19 testing access in low-income, Latinx communities