Tenacity Key to Success

When Andrew Webber ’10 gets excited, words tumble from his mouth so rapidly that it’s hard to keep up

Thermal reaction norms and the scale of temperature variation: latitudinal vulnerability of intertidal Nacellid limpets to climate change

The thermal reaction norms of 4 closely related intertidal Nacellid limpets, Antarctic (Nacella concinna), New Zealand (Cellana ornata), Australia (C. tramoserica) and Singapore (C. radiata), were compared across environments with different temperature magnitude, variability and predictability, to test their relative vulnerability to different scales of climate warming. Lethal limits were measured alongside a newly developed metric of “duration tenacity”, which was tested at different temperatures to calculate the thermal reaction norm of limpet adductor muscle fatigue. Except in C. tramoserica which had a wide optimum range with two break points, duration tenacity did not follow a typical aerobic capacity curve but was best described by a single break point at an optimum temperature. Thermal reaction norms were shifted to warmer temperatures in warmer environments; the optimum temperature for tenacity (Topt) increased from 1.0°C (N. concinna) to 14.3°C (C. ornata) to 18.0°C (an average for the optimum range of C. tramoserica) to 27.6°C (C. radiata). The temperature limits for duration tenacity of the 4 species were most consistently correlated with both maximum sea surface temperature and summer maximum in situ habitat logger temperature. Tropical C. radiata, which lives in the least variable and most predictable environment, generally had the lowest warming tolerance and thermal safety margin (WT and TSM; respectively the thermal buffer of CTmax and Topt over habitat temperature). However, the two temperate species, C. ornata and C. tramoserica, which live in a variable and seasonally unpredictable microhabitat, had the lowest TSM relative to in situ logger temperature. N. concinna which lives in the most variable, but seasonally predictable microhabitat, generally had the highest TSMs. Intertidal animals live at the highly variable interface between terrestrial and marine biomes and even small changes in the magnitude and predictability of their environment could markedly influence their future distributions

Alumni Profile

Feature about a Linfield alumnus or alumna. In this issue, Michelle Johnston-Holthaus \u2795: Tenacity Key to Success

Investing in Young Men of Color as Community Assets

Living in resource-poor communities, many young men of color have less access to high-performing and adequately funded schools, opportunities to work, positive youth development experiences, and social capital. However, many young men of color in poor and low-income communities are thriving; their resilience and tenacity, as well as local leadership, positive adult connections, and effective programs, have helped them overcome the odds

Cotton breeding in French-speaking Africa: Milestones and prospects

When cotton breeding programmes were first set up in French-speaking Africa in 1946, breeders were already taking the needs of different cotton stakeholders into account. The main breeding targets were productivity, resistance to pests and major cotton diseases, ginning outturn and fibre quality. The aim of this paper is to demonstrate how breeding has enhanced the performance of African cotton subsectors through presentation of results and experimental data from multilocation trials. Briefly, breeders have focused on Gossypium hirsutum cultivars, thus giving rise to plants with a relatively long growth cycle, that are vegetative and very floriferous, with delayed boll ripening (facilitating manual harvest), with a capacity to adapt to biotic and abiotic stress conditions, and with resistance to bacteriosis. Substantial gains were achieved in terms of productivity, ginning outturn and fibre quality (length, tenacity, fineness, and colorimetry). More than 90 cotton cultivars have been bred and released over a 60-year period. Genetic progress has, however, been limited in the last decade and African breeders will have to adopt new technologies to achieve further improvement in important traits. (Résumé d'auteur

Mechanical properties of wool and cotton yarns used in twenty-first century tapestry: preparing for the future by understanding the present

The conservation of historic tapestries is a complex and highly skilled task. Tapestries now being woven will need conservation in years to come. Can we, by understanding the properties of these contemporary works, assist the conservators of the future? The recreation of the Hunt of the Unicorn tapestries being undertaken by the West Dean Tapestry Studio offers a unique opportunity to access the materials being used and to create a body of data on their initial properties. This study uses tensile testing of the warp and weft materials to determine their maximum load at break, extension at maximum load, and specific stress (tenacity). Wool weft yarns from two different sources and of two thicknesses were examined. These wools were dyed ‘in house’ and the effect of the different dyes used was also assessed. These parameters all showed some significant (P < 0.05) differences. Cotton warp yarns of differing thickness and a gold thread were also tested. The comparison of how cotton and wool break demonstrates that when a tapestry is put under sufficient stress the cotton will snap but the wool may only stretch. However, this could often be beyond its recovery range resulting in a failure to return to shape

Study the effect of scouring time on Grewia asiatica (Phalsa) fibres properties

This research work was carried out to investigate the influence of treatment time period on physical properties of water retted Grewia asiatica (Phalsa) fibres. The extracted fibres were subjected to chemical scouring with sodium hydroxide (20g/l) and ammonium oxalate (5g/l) at 100º C for 30 mins. and 60 mins. and their effect on tensile strength, elongation and fibres fineness was studied. It was found that as the time period for scouring increased from 30 mins. to 60 mins. elongation and fineness improved, whereas in case of tenacity for 30 mins. treatment, tenacity improved but 60 mins. scouring decreased the tenacity of the fibres

Climate 2030: A National Blueprint for a Clean Energy Economy (Executive Summary)

Courage of conviction, unyielding stamina to underscore the dangerous realities of unchanging lifestyle habits and doing business as usual in today’s world, and unfettered tenacity necessary to build an ever-growing network of dedicated individuals and scientists struggling to express the need for public awareness and governmental action, describes this nationwide group. The Union of Concerned Scientists, primarily headquartered in Cambridge, Massachusetts, presents its forecast for 2030 – complete with the recipe needed to be undertaken for individuals and businesses to both survive and thrive