CATMoS: Collaborative Acute Toxicity Modeling Suite.

BACKGROUND: Humans are exposed to tens of thousands of chemical substances that need to be assessed for their potential toxicity. Acute systemic toxicity testing serves as the basis for regulatory hazard classification, labeling, and risk management. However, it is cost- and time-prohibitive to evaluate all new and existing chemicals using traditional rodent acute toxicity tests. In silico models built using existing data facilitate rapid acute toxicity predictions without using animals. OBJECTIVES: The U.S. Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM) Acute Toxicity Workgroup organized an international collaboration to develop in silico models for predicting acute oral toxicity based on five different end points: Lethal Dose 50 (LD50 value, U.S. Environmental Protection Agency hazard (four) categories, Globally Harmonized System for Classification and Labeling hazard (five) categories, very toxic chemicals [LD50 (LD50≤50mg/kg)], and nontoxic chemicals (LD50>2,000mg/kg). METHODS: An acute oral toxicity data inventory for 11,992 chemicals was compiled, split into training and evaluation sets, and made available to 35 participating international research groups that submitted a total of 139 predictive models. Predictions that fell within the applicability domains of the submitted models were evaluated using external validation sets. These were then combined into consensus models to leverage strengths of individual approaches. RESULTS: The resulting consensus predictions, which leverage the collective strengths of each individual model, form the Collaborative Acute Toxicity Modeling Suite (CATMoS). CATMoS demonstrated high performance in terms of accuracy and robustness when compared with in vivo results. DISCUSSION: CATMoS is being evaluated by regulatory agencies for its utility and applicability as a potential replacement for in vivo rat acute oral toxicity studies. CATMoS predictions for more than 800,000 chemicals have been made available via the National Toxicology Program's Integrated Chemical Environment tools and data sets (ice.ntp.niehs.nih.gov). The models are also implemented in a free, standalone, open-source tool, OPERA, which allows predictions of new and untested chemicals to be made. https://doi.org/10.1289/EHP8495

Sharing and community curation of mass spectrometry data with Global Natural Products Social Molecular Networking

The potential of the diverse chemistries present in natural products (NP) for biotechnology and medicine remains untapped because NP databases are not searchable with raw data and the NP community has no way to share data other than in published papers. Although mass spectrometry techniques are well-suited to high-throughput characterization of natural products, there is a pressing need for an infrastructure to enable sharing and curation of data. We present Global Natural Products Social molecular networking (GNPS, http://gnps.ucsd.edu), an open-access knowledge base for community wide organization and sharing of raw, processed or identified tandem mass (MS/MS) spectrometry data. In GNPS crowdsourced curation of freely available community-wide reference MS libraries will underpin improved annotations. Data-driven social-networking should facilitate identification of spectra and foster collaborations. We also introduce the concept of ‘living data’ through continuous reanalysis of deposited data

Orchard floor management effects on nitrogen fertility and soil biological activity in a newly established organic apple orchard.

Abstract This study addresses the often-competing goals of organic fertility and weed control by evaluating alternative orchard floor management strategies for their impact on N cycling, tree performance, and soil biological activity in a newly established apple (Malus domestica Borkh.) orchard. The standard tillage weed control practice resulted in satisfactory tree growth with desirable levels of leaf N and most other nutrients; however, soil biological activity did not improve. Maintenance of a living cover understory increased soil N concentration and availability and improved soil biological activity; however, tree growth was less than in other treatments likely in response to competition with the living cover understory for space and water. Application of wood chip mulch resulted in exceptional tree growth which may have resulted from greater water availability, but available soil N was lower, and consequently, tree leaf N concentration was low; in addition, soil biological activity was not improved. Clove oil organic herbicide provided poor weed control resulting in lower leaf N and tree growth and did not improve soil biological activity. Brassicaceae seed meal applications enhanced N availability and soil nematode abundance, but leaf N and many other nutrients were below desirable levels, and additional research is needed to optimize this treatment. We conclude that meeting the multiple objectives of weed control, optimal tree health, and increased soil biological activity may require employment of different orchard floor management strategies at different times during the life of the orchard

Características produtivas da batata-doce em função de doses de P2O5, de espaçamentos e de sistemas de plantio Yield characteristic of sweet potato affected by P2O5 levels, in the spacings and planting systems

Com o objetivo de avaliar a influência da adubação fosfatada, espaçamentos e sistemas de plantio na produção de raízes de batata-doce cv. Rainha Branca, conduziu-se um experimento no período de fevereiro a julho de 2004 em um NEOSSOLO REGOLÍTICO Psamítico típico, textura areia-franca, na Universidade Federal da Paraíba, Areia-PB. O delineamento experimental empregado foi de blocos casualizados em parcelas subdivididas com quatro repetições. Nas parcelas, foram testados vinte tratamentos formados por cinco doses de P2O5 (0, 100, 200, 300 e 400 kg ha-1), combinado fatorialmente com quatro espaçamentos entre plantas (0,20, 0,30, 0,40 e 0,50 m) por 0,80 m entre linhas; e nas subparcelas, dois sistemas de plantio (uma e duas ramas/cova). A maior produção de raízes comerciais/planta (662 g) foi obtida no sistema de plantio com uma rama/cova, no espaçamento de 0,80 m x 0,50 m (25.000 plantas ha-1), na dose estimada de 180 kg ha-1 de P2O5, enquanto que a menor (108 g), no espaçamento de 0,80 m x 0,20 m com duas ramas/cova, na ausência de P2O5. A produtividade comercial de raízes de batata-doce, em resposta às doses de fósforo no sistema de plantio com uma rama/cova, foi de 18,7 t ha-1, obtida com 210 kg de P2O5 ha-1. No sistema de plantio com duas ramas/cova, essa produtividade foi de 18,9 t ha-1, alcançada com 231 kg de P2O5 ha-1. A maior produtividade de raízes comerciais em função dos espaçamentos (19,64 t ha-1) foi obtida com 0,30 m entre plantas, no sistema de plantio com duas ramas/cova (83.330 plantas ha-1).<br>The influence of phosphate fertilization, spacing and planting systems were evaluated on the yield of sweet potato roots Rainha Branca cv. The experiment was carried out from February to July/2004 in Quartz Psamment soil, in the Universidade Federal of Paraíba, Areia-PB, Brazil. It was used experimental design of randomized blocks in sub divided plots in four replications. In the main plots, twenty treatments were tested forming five levels of P2O5 (0, 100, 200, 300 and 400 kg ha-1), combined factorially with four spacing among plants (0.20, 0.30, 0.40 and 0.50 m) for 0.80 m among lines; and in subplots, two planting for ms (one and two stems/hole). The largest production of commercial/plant roots (662 g) was obtained in planting system with a stems/hill, in the spacing of 0.80 m x 0.50 m (25.000 plants ha-1) with 180 kg ha-1 of P2O5. The commercial roots productivity of sweet potato roots, considering P2O5 levels at planting system with one stems/hole, were 18.7 t ha-1 obtained with 210 kg ha-1 of P2O5. The productivity in the planting system using two stems/hole were 18.9 t ha-1, and it was reached with 231 kg ha-1 of P2O5. The largest productivity on spacing function (19.64 t ha-1) was obtained with 0.30 m among plants, in the planting system with two stems/holes (83.330 plants ha-1)