9,890 research outputs found
Toxicogenomics to Improve Comprehension of the Mechanisms Underlying Responses of In Vitro and In Vivo Systems to Nanomaterials: A Review
No full textEngineered nanomaterials are commonly defined as materials with at least one dimension of 100 nanometers or less. Such materials typically possess nanostructure-dependent properties (e.g., chemical, mechanical, electrical, optical, magnetic, biological), which make them desiderable for commercial or medical application. However, these same properties may potentially lead to nanostructure-dependent biological activity that differs from and is not directly predicted by the bulk properties of the constitutive chemicals and compounds. Nanoparticles and nanomaterials can be on the same scale of living cells components, including proteins, nucleic acids, lipids and cellular organelles. When considering nanoparticles it must be asked how man-made nanostructures can interact with or influence biological systems. Carbon nanotubes (CNTs) are an example of carbon-based nanomaterial, which has won a huge spreading in nanotechnology. The incorporation of CNTs in living systems has raised many concerns because of their hydrophobicity and tendency to aggregate and accumulate into cells, organs, and tissues with dangerous effects. Applications of toxicogenomics to both investigative and predictive toxicology will contribute to the in-depth investigation of molecular mechanisms or the mode of nanomaterials action that is achieved by using conventional toxicological approaches. Parallel toxicogenomic technologies will promote a valuable platform for the development of biomarkers, in order to predict possible nanomaterial's toxicity. The potential of characteristic gene expression profiles ("fingerprint") of exposure or toxicological response to nanoparticles will be discussed in the review to enhance comprehension of the molecular mechanism of in vivo and in vitro system exposed to nanomaterials
Metadata Representations for Queryable ML Model Zoos
No full textMachine learning (ML) practitioners and organizations are building model zoos of pre-trained models, containing metadata describing properties of the ML models and datasets that are useful for reporting, auditing, reproducibility, and interpretability purposes. The metatada is currently not standardised; its expressivity is limited; and there is no interoperable way to store and query it. Consequently, model search, reuse, comparison, and composition are hindered. In this paper, we advocate for standardized ML model metadata representation and management, proposing a toolkit supported to help practitioners manage and query that metadata.Web Information SystemsHuman-Centred Artificial Intelligenc
A Manifesto of Nodalism
No full textThis paper proposes the notion of Nodalism as a means describing contemporary culture and of understanding my own creative practice in electronic music composition. It draws on theories and ideas from Kirby, Bauman, Bourriaud, Deleuze, Guatarri, and Gochenour, to demonstrate how networks of ideas or connectionist neural models of cognitive behaviour can be used to contextualize, understand and become a creative tool for the creation of contemporary electronic music
Optimizing ML Inference Queries Under Constraints
No full textThe proliferation of pre-trained ML models in public Web-based model zoos facilitates the engineering of ML pipelines to address complex inference queries over datasets and streams of unstructured content. Constructing optimal plan for a query is hard, especially when constraints (e.g. accuracy or execution time) must be taken into consideration, and the complexity of the inference query increases. To address this issue, we propose a method for optimizing ML inference queries that selects the most suitable ML models to use, as well as the order in which those models are executed. We formally define the constraint-based ML inference query optimization problem, formulate it as a Mixed Integer Programming (MIP) problem, and develop an optimizer that maximizes accuracy given constraints. This optimizer is capable of navigating a large search space to identify optimal query plans on various model zoos.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Web Information SystemsHuman-Centred Artificial Intelligenc
Polymeric micelles for cutaneous delivery of resveratrol
No full textPurpose: The efficacy of resveratrol (RES) in preventing skin aging and protecting epidermis from damages induced by UVA and UVB has been recently demonstrated (Soeur et al., 2015). Considering the low skin penetration of UV rays, the design of delivery systems able to promote the RES localization into the epidermis resulted of interest to guarantee skin protection. The present study aimed to evaluate the feasibility of poloxamer micelles for enhancing the RES penetration in the upper skin layers.
Methods: 0.1% w/v RES-loaded polymeric micelles were prepared using solvent diffusion method (acetone solution/water: 1/10 v/v). Poloxamer 118 (P118) and 407 (P407) were selected as excipients because of their high solubility in water, other than the different molecular weight and HLB value. To study the impact of polymer composition on the physical properties and stability of RES-loaded polymeric micelles, different formulations were prepared using different concentrations of polymers (0.1-1.0% w/v), as single polymer or 1:1 mixture. The resulting nanosystems were characterized in terms of particle size, ζ-potential and apparent solubility of RES in water. Their physical stability was also checked over 1 month at room temperature. Release studies through artificial membrane (i.e., Cuprophan®) and in vitro permeation studies through full-thickness porcine ear skin were performed over 24 h by using Franz cells.
Results: Poloxamers can auto-assemble in nano-micelles when RES was added to the formulation. The size of micelles ranged from 30 to 300 nm, as function of their compositions; ζ-potential was almost neutral for all formulations. In micellar systems containing P407, the RES apparent solubility significantly increased (1.05±0.7 mg/mL) with respect to a saturated solution (0.04±0.00 mg/mL). Similar results were observed with P118, but it had a lower solubilizing efficiency (0.36±0.33 mg/mL). The release study suggested that micelles could act as nano-reservoir systems for RES. Indeed, the RES amount diffused through Cuprophan® membrane within 8h (<5%) was six-time lower for polymeric micelles in comparison to the control solution (≈30%). Among micellar systems, the diffused RES amounts increased in the order: P407 < P118/P407 (1:1) ≈ P118. In vitro permeation study demonstrated that the RES permeation through full-thickness porcine skin was negligible for all tested formulations and the RES retention in the deep epidermal and dermal layers resulted lower than 1% of total RES loaded. Nevertheless, the stripping technique revealed that micellar formulations were more efficient in promoting the penetration and retention of RES than control (p < 0.01) in the upper epidermal layers. Interestingly, micelles made of P188 and P407 (1:1) could enhance the permeation of RES in the lower epidermal layers more than other micellar systems and control (p < 0.05).
Conclusions: Poloxamers can auto-assemble in presence of RES to form micellar systems, enhancing significantly its apparent solubility in water. Micelles made of P188 and P407 resulted promising nanocarriers for enhancing the skin partition of RES and its localization in the upper skin layers.
References
Soeur J et al. Skin resistance to oxidative stress induced by resveratrol: From Nrf2 activation to GSH biosynthesis. Free Radical Biology and Medicine 2015, 78, 213-223
PomA mutation or deletion suppressed <i>sepH1</i> defects in septation and conidiation.
No full text(A) Colony morphologies of the wild type (TN02A7), sepH1, ΔpomA, PomAL1265S, sepH1 ΔpomA and sepH1 PomAL1265S strains cultured on YUU at 30 or 42 °C for 2 days. (B) Septa comparison in hyphal cells stained with CFW in the indicated strains cultured in liquid rich media YUU at 42 °C for 20 h. Arrows indicate the locations of septa. Bars, 10 μm. (C) Localization of GFP-PomA under control of the alcA conditional promoter when strain ZXA14 was cultured with liquid minimal media PGRT. Bars, 10 μm. (D) Colony morphologies of the indicated strains cultured on YAG medium or YAG medium supplemented with 1 M KCl, 1 M NaCl, calcofluor white (CFW) (50 μg/ml), Congo red (CR) (100 μg/ml) and caspofungin (1.25 μg/ml) at 37 °C for 2 days. (E) Germling morphological comparison by differential interference contrast (DIC) images of the parental wild type (TN02A7) and ΔpomA strains cultured in liquid media YUU for 8 h. Bars, 10 μm. (F) Morphological comparison of hyphal cells labeled with an RFP-histone H2A tag showing nuclei distribution and strained with CFW showing septa in the related strains cultured in liquid medium YUU at 37 °C for 7 h. Bars, 10 μm. (G) Comparison of formed septa in hyphal cells stained with CFW in the parental wild type (TN02A7) and OE::pomA strains cultured in liquid media YUU at 37 °C for 10 h. Bars, 10 μm.</p
Cytotoxicity and Genotoxicity of Ceria Nanoparticles on Different Cell Lines in Vitro
No full textOwing to their radical scavenging and UV-filtering properties, ceria nanoparticles (CeO2-NPs) are currently used for various applications, including as catalysts in diesel particulate filters. Because of their ability to filter UV light, CeO2-NPs have garnered significant interest in the medical field and, consequently, are poised for use in various applications. The aim of this work was to investigate the effects of short-term (24 h) and long-term (10 days) CeO2-NP exposure to A549, CaCo2 and HepG2 cell lines. Cytotoxicity assays tested CeO2-NPs over a concentration range of 0.5 mu g/mL to 5000 mu g/mL, whereas genotoxicity assays tested CeO2-NPs over a concentration range of 0.5 mu g/mL to 5000 mu g/mL. In vitro assays showed almost no short-term exposure toxicity on any of the tested cell lines. Conversely, long-term CeO2-NP exposure proved toxic for all tested cell lines. NP genotoxicity was detectable even at 24-h exposure. HepG2 was the most sensitive cell line overall; however, the A549 line was most sensitive to the lowest concentration tested. Moreover, the results confirmed the ceria nanoparticles' capacity to protect cells when they are exposed to well-known oxidants such as H2O2. A Comet assay was performed in the presence of both H2O2 and CeO2-NPs. When hydrogen peroxide was maintained at 25 mu M, NPs at 0.5 mu g/mL, 50 mu g/mL, and 500 mu g/mL protected the cells from oxidative damage. Thus, the NPs prevented H2O2-induced genotoxic damage
Building a generalisable ML pipeline at ING
No full textAdvances in data science have caused an increase in the use of Artificial Intelligence (AI), specifically Machine Learning (ML), throughout various fields. Not only in research but in the industry as well, has ML been receiving increasing amounts of interest. Many companies rely on ML models to increase the efficiency of existing processes or offer new services and products. The industry, however, is facing several additional challenges compared to the academic context. One of those challenges is applying the Development Operations (DevOps) model to an ML application, also referred to as MLOps. This thesis sets out to find the specific challenges that practitioners encounter while operationalising ML models. To do so, we perform a single-case case study on an ML pipeline built by the Trade & Communication Surveillance team at the ING bank. This case study consists of conducting a set of interviews and performing a manual code inspection of the pipeline. The team faces challenges ranging from having insufficient time for operationalising each ML project individually to operating in the highlyregulated fintech context. Their pipeline is able to deploy a single ML model but it does not generalise well to other projects. We present the first version of an application that mitigates these challenges. The application is able to deploy ML models to the development environment at ING and can be operated by data scientists to reduce the effort of operationalising an ML model. Computer Science | Software Technolog
'Project smells' - Experiences in Analysing the Software Quality of ML Projects with mllint
No full textMachine Learning (ML) projects incur novel challenges in their development and productionisation over traditional software applications, though established principles and best practices in ensuring the project's software quality still apply. While using static analysis to catch code smells has been shown to improve software quality attributes, it is only a small piece of the software quality puzzle, especially in the case of ML projects given their additional challenges and lower degree of Software Engineering (SE) experience in the data scientists that develop them. We introduce the novel concept of project smells which consider deficits in project management as a more holistic perspective on software quality in ML projects. An open-source static analysis tool mllint was also implemented to help detect and mitigate these. Our research evaluates this novel concept of project smells in the industrial context of ING, a global bank and large software- and data-intensive organisation. We also investigate the perceived importance of these project smells for proof-of-concept versus production-ready ML projects, as well as the perceived obstructions and benefits to using static analysis tools such as mllint. Our findings indicate a need for context-aware static analysis tools, that fit the needs of the project at its current stage of development, while requiring minimal configuration effort from the user. Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Software EngineeringSoftware Technolog
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