RUI: Developing a regression model predicting the toxicity of metal nanoparticles against soil microbial community

活跃和多样的微生物群落对土壤至关重要;因此对农业，粮食安全和生态系统健康至关重要。 这些群落的变化可以显著影响土壤质量、健康和生产力。 本研究使用实验和统计/建模方法来调查和预测常见的金属纳米颗粒（铁，铜，和银），据报道，具有抗菌性能，对土壤微生物群落的影响。 主要研究目标是开发模型，可以帮助评估常见金属纳米颗粒的生态毒性，而不必对每个待测样品进行大量实验。 这项工作通过实验/建模相结合的方法实现了这一目标。 涉及十个重要的土壤参数（pH值，温度，纳米颗粒浓度，有机碳含量，土壤水分，以及各种阳离子和阴离子，如Na，Ca，Mg，硝酸盐和磷酸盐的浓度）对选定的商业购买的纳米颗粒和两个模型土壤之间的相互作用的毒性研究的实验，每个模型土壤都有其独特的微生物群落，将在微观世界中进行。 将使用三种不同的微生物健康和代谢活性指标评估纳米颗粒对微生物群落的毒性：PCR-DGGE、Biolog Ecoplates和总土壤FAME分析，从中可以确定单个生态毒性值。 实验矩阵的结果将用于开发一个线性回归模型，该模型将确定增加、减少或不影响土壤微生物毒性的环境参数。 将开发二次回归，建立线性模型的结果，以预测每个参数的潜在毒性，并确定和评估各种环境参数之间的相互作用。 该研究的更广泛的影响包括研究和教育的紧密结合，使大量本科生参与环境生物学研究，并利用研究来增加本科课程。 通过夏季的研究经验，该项目还将吸引南方大学的学生，南方大学是一所历史悠久的黑人大学，目前仍在从卡特里娜飓风的影响中恢复过来。 通过从道林学院少数民族教师发展和培训方案中心招募学生参加研究，也将增加代表性不足的群体在科学领域的参与。 还将举办为公众量身定制的免费公开讲座，以提高他们对环境影响的认识。

Active and diverse microorganism communities are essential for soil; and hence for agriculture, food security, and ecosystem health. Changes in these communities can significantly influence soil quality, health, and productivity. This research uses experimental and statistical/modeling approaches to investigate and predict the impact of common metal nanoparticles (iron, copper, and silver), which are reported to have anti-microbial properties, on soil microbial communities. The main research goal is to develop models that can help assess the ecotoxicity of common metal nanoparticles without having to resort to carrying out large numbers of experiments for each sample to be tested. This work accomplishes that goal with a combined experimental/modeling approach. Experiments involving the study of the toxicity of ten important soil parameters (pH, temperature, nanoparticle concentration, organic carbon content, soil moisture, and the concentration of various cations and anions like Na, Ca, Mg, nitrates, and phosphates) on the interaction between selected commercially purchased nanoparticles and two model soils, each with their unique microbial community, will be carried out in microcosms. The toxicity of the nanoparticles to microbial communities will be evaluated using three different indicators of microbial health and metabolic activity: PCR-DGGE, Biolog Ecoplates, and total soil FAME analyses from which a single ecotoxicity value can be determined. Results of the experimental matrix will be used to develop a linear regression model that will identify environmental parameters that increase, decrease, or have no influence on toxicity on the soil microbes. A quadratic regression will be developed that build off the results of the linear model to predict the toxic potential of each parameter and identify and assess interactions among the various environmental parameters. Broader impacts of the research include the strong integration of research and education, engaging large numbers of undergraduate students in environmental biology research, and using the research to augment undergraduate course curriculum. Through a summer research experience, the project will also engage students from Southern University, a historically black college that is still recovering from the effects of Hurricane Katrina. Participation of under-represented groups in the sciences will also be increased by recruiting students from the Dowling College Center for Minority Teacher Development and Training Program to participate in the research. Free public lectures tailored for the general public to increase their awareness of their impacts on the environment will also be presented.