250 research outputs found
Creating a more robust 5-hydroxymethylfurfural oxidase by combining computational predictions with a novel effective library design
Additional file 4: Figure S1. Michaelis–Menten graph of WT and 7xHMFO. Kinetic assay performed with HRP peroxidase in 50 mM phosphate buffer pH 8.0 at 25 °C using HMF as substrate
Managing Vegetation In Grassland Habitats To Enhance Livestock Or Wildlife Objectives
Sustainably stewarding grassland systems involves applying various practices to manipulate forage interactions with other plants, the environment, and grazing animals to meet resource manager objectives. These interactions can result in invasion or encroachment and increased abundance of weeds which hinder attainment of management objectives. Weeds influence the structure and function of pasture ecosystems whether forages are grown in improved pastures, rangeland, or grassland communities. They degrade pasture quality and reduce livestock performance by interfering with forage establishment, yield, and quality by competing for resources. Weeds reduce the feed value of forage, decrease pasture carrying capacity, and can be toxic or unpalatable to livestock. Managing weeds requires use of vegetation management tools that favor desirable forages. Herbicides can be a catalyst that expedite grassland renovation, improve the forage resource, and increase carrying capacity. Corteva Agriscience has a variety of herbicide products that provide superior control of herbaceous and woody weeds, while maintaining the desirable vegetation. These herbicides were designed and developed specifically for selective broadleaf weed control in rangeland, pastures, rights-of-way, non-cropland, and natural areas. Active ingredients historically used include aminopyralid, triclopyr, fluroxypyr, clopyralid, and picloram. Rinskor™ active and Arylex™ active are new herbicide active ingredients from Corteva Agriscience™ and are members of a unique synthetic auxin chemotype, the arylpicolinates (HRAC group O / WSSA group 4). Members of the arylpicolinate family demonstrate novel and differentiated characteristics in terms of use rate, spectrum, weed symptoms, environmental fate, and molecular interaction as compared to other auxin chemotypes. When applied as a stand-alone treatment or in various mixes these products are safe to desirable grass species and control key herbaceous and woody weeds in the genera Ambrosia, Acacia, Carduus, Centaurea, Cirsium, Mimosa, Prosopis, Ranunculus, Rumex, Sida, Solanum, Taraxacum, and more
Dissolved inorganic nutrients and chlorophyll on the narrow continental shelf of Eastern Brazil
The eastern Brazilian continental shelf is narrow and subject to the influence of a western boundary current system, presenting lower biological productivity than other regions. In this study, the distribution of water masses, dissolved inorganic nutrients, chlorophyll-a and total suspended solids (TSS) on the inner shelf (< 35 m depth), between Itacaré and Canavieiras, eastern Brazil, is presented. Sampling surveys were carried out in March and August 2006 and March 2007. Tropical water (TW) prevailed during March 2006 and August 2007 with the lower salinity waters (< 36) found in most samples taken in March 2007, reflecting the influence of continental outflow and rain in coastal waters. Low concentrations of dissolved inorganic nutrients and Chl-a found were typical of TW and results suggested that the inner shelf waters were depleted in dissolved inorganic nitrogen in August 2006 and March 2007, and in phosphate in March 2006, potentially affecting phytoplankton growth. Stratification of the water column was observed due to differences in dissolved nutrient concentrations, chlorophyll-a and TSS when comparing surface and bottom samples, possibly the result of a colder water intrusion and mixing on the bottom shelf and a deep chlorophyll maximum and/or sediment resuspension effect. Despite this stratification, oceanographic processes such as lateral mixing driven by the Brazil Current as well as a northward alongshore drift driven by winds and tides transporting Coastal Water can lead to an enhanced mixing of these waters promoting some heterogeneity in this oligotrophic environment
Queer In AI: A Case Study in Community-Led Participatory AI
Queerness and queer people face an uncertain future in the face of ever more widely deployed and invasive artificial intelligence (AI). These technologies have caused numerous harms to queer people, including privacy violations, censoring and downranking queer content, exposing queer people and spaces to harassment by making them hypervisible, deadnaming and outing queer people. More broadly, they have violated core tenets of queerness by classifying and controlling queer identities. In response to this, the queer community in AI has organized Queer in AI, a global, decentralized, volunteer-run grassroots organization that employs intersectional and community-led participatory design to build an inclusive and equitable AI future. In this paper, we present Queer in AI as a case study for community-led participatory design in AI. We examine how participatory design and intersectional tenets started and shaped this community’s programs over the years. We discuss different challenges that emerged in the process, look at ways this organization has fallen short of operationalizing participatory and intersectional principles, and then assess the organization’s impact. Queer in AI provides important lessons and insights for practitioners and theorists of participatory methods broadly through its rejection of hierarchy in favor of decentralization, success at building aid and programs by and for the queer community, and effort to change actors and institutions outside of the queer community. Finally, we theorize how communities like Queer in AI contribute to the participatory design in AI more broadly by fostering cultures of participation in AI, welcoming and empowering marginalized participants, critiquing poor or exploitative participatory practices, and bringing participation to institutions outside of individual research projects. Queer in AI’s work serves as a case study of grassroots activism and participatory methods within AI, demonstrating the potential of community-led participatory methods and intersectional praxis, while also providing challenges, case studies, and nuanced insights to researchers developing and using participatory methods
A Genomic Approach for the Identification and Classification of Genes Involved in Cell Wall Formation and its Regulation in Saccharomyces Cerevisiae
Using a hierarchical approach, 620 non-essential single-gene yeast deletants generated by
EUROFAN I were systematically screened for cell-wall-related phenotypes. By analyzing
for altered sensitivity to the presence of Calcofluor white or SDS in the growth medium,
altered sensitivity to sonication, or abnormal morphology, 145 (23%) mutants showing at
least one cell wall-related phenotype were selected. These were screened further to identify
genes potentially involved in either the biosynthesis, remodeling or coupling of cell wall
macromolecules or genes involved in the overall regulation of cell wall construction and to
eliminate those genes with a more general, pleiotropic effect. Ninety percent of the mutants
selected from the primary tests showed additional cell wall-related phenotypes. When
extrapolated to the entire yeast genome, these data indicate that over 1200 genes may
directly or indirectly affect cell wall formation and its regulation. Twenty-one mutants with
altered levels of β1,3-glucan synthase activity and five Calcofluor white-resistant mutants
with altered levels of chitin synthase activities were found, indicating that the
corresponding genes affect β1,3-glucan or chitin synthesis. By selecting for increased
levels of specific cell wall components in the growth medium, we identified 13 genes that
are possibly implicated in different steps of cell wall assembly. Furthermore, 14 mutants
showed a constitutive activation of the cell wall integrity pathway, suggesting that they
participate in the modulation of the pathway either directly acting as signaling components
or by triggering the Slt2-dependent compensatory mechanism. In conclusion, our screening
approach represents a comprehensive functional analysis on a genomic scale of gene
products involved in various aspects of fungal cell wall formation
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