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Although water is essential for life, as per the United Nations, around 2 billion people in this world lack access to safely managed drinking water services at home. Herein we report the development of a two-dimensional (2D) fluorinated graphene oxide (FGO) and polyethylenimine (PEI) based three-dimensional (3D) porous nanoplatform for the effective removal of polyfluoroalkyl substances (PFAS), pharmaceutical toxins, and waterborne pathogens from contaminated water. Experimental data show that the FGO-PEI based nanoplatform has an estimated adsorption capacity (qm) of â¼219 mg g-1 for perfluorononanoic acid (PFNA) and can be used for 99% removal of several short- and long-chain PFAS. A comparative PFNA capturing study using different types of nanoplatforms indicates that the qm value is in the order FGO-PEI > FGO > GO-PEI, which indicates that fluorophilic, electrostatic, and hydrophobic interactions play important roles for the removal of PFAS. Reported data show that the FGO-PEI based nanoplatform has a capability for 100% removal of moxifloxacin antibiotics with an estimated qm of â¼299 mg g-1. Furthermore, because the pore size of the nanoplatform is much smaller than the size of pathogens, it has a capability for 100% removal of Salmonella and Escherichia coli from water. Moreover, reported data show around 96% removal of PFAS, pharmaceutical toxins, and pathogens simultaneously from spiked river, lake, and tap water samples using the nanoplatform.
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The accessibility and popularity of additive manufacturing (AM) has increased over the past decade. Environmental hazard assessment and safety data sheets for 3D printer feedstocks has lagged technology development. Vat photopolymerization may have unique risks relative to other AM technologies due to mishandling of uncured monomers/oligomer feedstocks and its decreasing cost enabling uninformed residential use. The acute and chronic toxicity of six uncured resins to Ceriodaphnia dubia was explored. Two-day acute toxicity (LC50) ranged from 2.6 to 33 mg/L and inhibition concentrations (IC25) values for reproduction ranged from 0.33 to 16 mg/L. Cleaning and waste management procedures recommended in user guides could be the most hazardous handling scenario as use of isopropyl alcohol increases miscibility and thus the fate, transport and bioavailability of the uncured resins. Residential users may often be poorly informed about potential toxicity and the need for a plan for use, handling, and waste management of uncured resins.
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Cladocera , Poluentes Químicos da Água , Animais , Testes de Toxicidade Crônica , Poluentes Químicos da Água/toxicidade , Cladocera/fisiologia , Impressão TridimensionalRESUMO
INTRODUCTION: Rural communities often face chronic challenges of high rates of serious health conditions coupled with inadequate access to health care services-challenges exacerbated by the COVID-19 pandemic. One strategy with the potential to mitigate these problems is the increased use of telehealth technology. A feature of telehealth applications-collaboration between health care providers for consultation and other purposes-referred to herein as Rural Provider-to-Provider Telehealth (RPPT), introduces important expertise that may not exist locally in rural communities. Literature indicates that RPPT is operationalized through many methods with an array of purposes. While RPPT is a promising strategy that brings additional expertise to patient-centered rural care delivery, there is limited evidence addressing important considerations, including how patient access and outcomes, provider satisfaction and performance, and payment may be affected by its use. METHODS: Recognizing the significant potential of RPPT and the need for more information associated with its use, the National Institutes of Health convened a Pathways to Prevention (P2P) workshop to further understand RPPT's effectiveness and impact on improving health outcomes in rural settings. The P2P initiative, supported by several federal health agencies, engaged rural health stakeholders and experts to examine four key questions, identify related knowledge gaps, and provide recommendations to advance understanding of the use and impact of RPPT. RESULTS: Included in this report is a description of the process used to generate information about RPPT, the identification of key knowledge gaps, and specific recommendations to further build needed evidence. DISCUSSION: The emerging use of RPPT is an important tool for bridging gaps in access to care that impacts rural populations. However, to fully understand the value and effects of RPPT, new research is needed to fill the knowledge gaps identified in this report. Additionally, this report should help engage providers, payors, and policymakers interested in supporting evidence-informed RPPT practice, policy, and payment, with the ultimate aim of improving access to health care and health status of rural communities in the United States and worldwide.
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This study examined natural composite structures within the remarkably strong exoskeleton of the southwestern ironclad beetle (Z. haldemani). Structural and nanomechanical analyses revealed that the exoskeleton's extraordinary resistance to external forces is provided by its exceptional thickness and multi-layered structure, in which each layer performed a distinct function. In detail, the epicuticle, the outmost layer, comprised 3%-5% of the overall thickness with reduced Young's moduli of 2.2-3.2 GPa, in which polygonal-shaped walls (2-3µm in diameter) were observed on the surface. The next layer, the exocuticle, consisted of 17%-20% of the total thickness and exhibited the greatest Young's moduli (â¼15 GPa) and hardness (â¼800 MPa) values. As such, this layer provided the bulk of the mechanical strength for the exoskeleton. While the endocuticle spanned 70%-75% of the total thickness, it contained lower moduli (â¼8-10 GPa) and hardness (â¼400 MPa) values than the exocuticle. Instead, this layer may provide flexibility through its specifically organized chitin fiber layers, known as Bouligand structures. Nanoindentation testing further reiterated that the various fibrous layer orientations resulted in different elastic moduli throughout the endocuticle's cross-section. Additionally, this exoskeleton prevented delamination within the composite materials by overlapping approximately 5%-19% of each fibrous stack with neighboring layers. Finally, the innermost layer, the epidermis contributing 5%-7 % of the total thickness, contains attachment sites for muscle and soft tissue that connect the exoskeleton to the beetle. As such, it is the softest region with reduced Young's modulus of â¼2-3 GPa and hardness values of â¼290 MPa. These findings can be applied to the development of innovative, fiber-reinforced composite materials.
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Besouros , Exoesqueleto Energizado , Animais , Módulo de Elasticidade , DurezaRESUMO
The overall goal of this study is to employ quantitative magnetic resonance imaging (MRI) data to constrain a patient-specific, computational fluid dynamics (CFD) model of blood flow and interstitial transport in breast cancer. We develop image processing methodologies to generate tumor-related vasculature-interstitium geometry and realistic material properties, using dynamic contrast enhanced MRI (DCE-MRI) and diffusion weighted MRI (DW-MRI) data. These data are used to constrain CFD simulations for determining the tumor-associated blood supply and interstitial transport characteristics unique to each patient. We then perform a proof-of-principle statistical comparison between these hemodynamic characteristics in 11 malignant and 5 benign lesions from 12 patients. Significant differences between groups (i.e., malignant versus benign) were observed for the median of tumor-associated interstitial flow velocity ( P = 0.028 ), and the ranges of tumor-associated blood pressure (P = 0.016) and vascular extraction rate (P = 0.040). The implication is that malignant lesions tend to have larger magnitude of interstitial flow velocity, and higher heterogeneity in blood pressure and vascular extraction rate. Multivariable logistic models based on combinations of these hemodynamic data achieved excellent differentiation between malignant and benign lesions with an area under the receiver operator characteristic curve of 1.0, sensitivity of 1.0, and specificity of 1.0. This image-based model system is a fundamentally new way to map flow and pressure fields related to breast tumors using only non-invasive, clinically available imaging data and established laws of fluid mechanics. Furthermore, the results provide preliminary evidence for this methodology's utility for the quantitative characterization of breast cancer.
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Neoplasias da Mama , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Meios de Contraste , Imagem de Difusão por Ressonância Magnética , Feminino , Hemodinâmica , Humanos , Hidrodinâmica , Imageamento por Ressonância Magnética , Curva ROC , Estudos Retrospectivos , Sensibilidade e EspecificidadeRESUMO
We investigate computationally the role of Stone-Wales (SW) defects on the interfacial interactions among graphene, carbon nanotubes (CNTs), and Nylon 6 using density functional theory (DFT) and the empirical force-field. Our first-principles DFT calculations were performed using the Quantum ESPRESSO electronic structure code with the highly accurate van der Waals functional (vdW-DF2). Both pristine and SW-defected carbon nanomaterials were investigated. The computed results show that the presence of SW defects on CNTs weakens the CNT-graphene interactions. Our result that CNT-graphene interaction is much stronger than CNT-CNT interaction indicates that graphene would be able to promote the dispersion of CNTs in the polymer matrix. Our results demonstrate that carbon nanomaterials form stable complexes with Nylon 6 and that the van der Waals interactions, as revealed by the electronic charge density difference maps, play a key stabilizing role on the interfacial interactions among graphene, CNTs, and Nylon 6. Using the density of states calculations, we observed that the bandgaps of graphene and CNTs were not significantly modified due to their interactions with Nylon 6. The Young's moduli of complexes were found to be the averages of the moduli of their individual constituents.
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This article presents the strain-based experimental data for Ti-6Al-4V ELI under non-constant amplitude cyclic loading. Uniaxial strain-controlled fatigue experiments were conducted under three different loading conditions, including two-level block loading (i.e. high-low and low-high), periodic overload, and variable amplitude loading. Tests were performed under fully-reversed, and mean strain/stress conditions. For each test conducted, two sets of data were collected; the cyclic stress-strain response (i.e. hysteresis loops) in log10 increments, and the peak and valley values of stress and strain for each cycle. Residual fatigue lives are reported for tests with two-level block loading, while for periodic overload and variable amplitude experiments, fatigue lives are reported in terms of number of blocks to failure.
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The unique behavior of engineered nanomaterials (ENM) in aqueous media and dynamic changes in particle settling, agglomeration and dissolution rates is a challenge to the consistency, reliability and interpretation of standard aquatic hazard bioassay results. While the toxicological endpoints (e.g., survival, growth, reproduction, etc.) in ecotoxicity bioassays are largely applicable to ENMs, the standard methods as written for dissolved substances are confounded by the dynamic settling, agglomeration and dissolution of particulate ENMs during the bioassay. A testing framework was designed to serve as a starting point to identify approaches for the consistent conduct of aquatic hazard tests that account for the behavior of ENMs in test media and suitable data collection to support representative exposure metrology. The framework was demonstrated by conducting three case studies testing ENMs with functionally distinct characteristics and behaviors. Pretests with a temporal sampling of particle concentration, agglomeration and dissolution were conducted on each ENM in test media. Results indicated that a silver nanoparticle (AgNP) powder was not dispersible, a nano-TiO2 powder was dispersible but unstable, and a polyvinylpyrrolidinone-coated AgNP was relatively stable in test media. Based on these functional results, Ceriodaphnia dubia bioassays were conducted to compare different exposure summary methods (nominal, arithmetic average, geometric average, time-weighted average) for calculating and expressing toxicity endpoints. Results indicated that while arithmetic means were effective for expressing the toxicity of more stable materials, time-weighted averaged concentrations were appropriate for the unstable nano-TiO2.
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Daphnia/efeitos dos fármacos , Ecotoxicologia/métodos , Nanopartículas/toxicidade , Prata/toxicidade , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Bioensaio , Reprodutibilidade dos Testes , Solubilidade , Testes de Toxicidade/métodosRESUMO
Neuroendocrine tumors in gastrointestinal (GI) tract are a rare source of GI malignancy with an estimated incidence of 2.5 - 5 per 100,000 people per year and the prevalence of 35 per 100,000. In the GI tract, they are located in decreasing order of frequency in appendix, ileum, rectum, stomach, and colon. Those found in the anal region represent just 1% of all malignancies of the anal canal. Their clinical presentation can be widely varying, sometimes being found incidentally with metastatic disease and an unknown primary source. We report a case of a 60-year-old male who presented with a 2-week history of intermittent bright red blood per rectum and anal pain. He was found to have a lesion in the perianal area which was subsequently diagnosed has a poorly differentiated large cell type neuroendocrine carcinoma (NEC) with hepatic metastasis.
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The United Nations (UN) estimates that more than one billion people in this world do not have access to safe drinking water due to microbial hazards and it kills more than 7.6 million children every year via waterborne diseases. Driven by the need for the removal and inactivation of waterborne pathogens in drinking water, we report the chemical design and details of microscopic characterization of a bio-conjugated chitosan attached carbon nanotube based three dimensional (3D) nanoporous architecture, which has the capability for effective separation and complete disinfection of waterborne pathogens from environmental water samples. In the reported design, chitosan, a biodegradable antimicrobial polysaccharide with an architecture-forming ability has been used for the formation of 3D pores as channels for water passage, as well as to increase the permeability on the inner and outer architectures for killing Rotavirus and Shigella waterborne pathogens. On the other hand, due to their large surface area, CNTs have been wrapped by chitosan to enhance the adsorption capability of the architecture for the separation and removal of pathogens from water. The reported data show that the anti-Rotavirus VP7 antibody and LL-37 antimicrobial peptide conjugated chitosan-CNT architecture can be used for efficient separation, identification and 100% eradication of Rotavirus and Shigella waterborne pathogens from water samples of different sources. A detailed mechanism for the separation and inactivation of waterborne pathogens using the bio-conjugated chitosan based 3D architecture has been discussed using microscopic and spectroscopic studies. Reported experimental data demonstrate that the multifunctional bio-conjugated 3D architecture has good potential for use in waterborne pathogen separation and inactivation technology.
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Tuberculous osteomyelitis is rare and usually involves the vertebrae but is seldom found in the foot. The uncommon site and ability to mimic other disorders clinically and radiographically leads to diagnostic and therapeutic delays. We report a case of a 40-year-old man who initially presented to his podiatrist with intermittent pain and swelling of his right ankle and foot that lasted for a year. He also started to exhibit significant weight loss and unexplained fevers and was subsequently hospitalized for cellulitis of his right foot. On further workup, patient was found to have miliary tuberculosis (TB) and acquired immunodeficiency syndrome (AIDS). Patient was treated with anti-TB therapy for 9 months and highly active anti-retroviral therapy. Our patient presented with ongoing chronic right foot and ankle pain that was proven to be secondary to TB osteomyelitis of cuneiform bones of the right ankle in the setting of AIDS. The patient's clinical presentation was unusual due to symptom duration and lack of systemic characteristics. Like our case, reported incidence of osteomyelitis of bone/joint in extrapulmonary TB is estimated to be 10%, and out of all bones/joint TB cases, only 1% are found to be in the foot.
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We report a 35-year-old healthy male who developed central nervous system inflammatory demyelinating disease consistent with tumefactive multiple sclerosis. About 2 weeks after onset of symptoms and prior to initiation of therapy, the patient had lymphopenia and low CD4 and CD8 levels. His lymphocyte count was 400 cells/µl (850-3,900 cells/µl), CD4 was 193 cells/µl (490-1,740 cells/µl) and CD8 was 103 cells/µl (180-1,170 cells/µl). He was treated with intravenous methylprednisolone followed by therapeutic plasma exchange, the levels of CD4 and CD8 normalized, and ultimately, he recovered completely.
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In this study a woodpecker's hyoid apparatus was characterized to determine its impact mitigation mechanism using finite element (FE) analysis. The woodpecker's hyoid apparatus, comprising bone and muscle, has a unique geometry compared to those of other birds. The hyoid starts at the beak tip, surrounds the woodpecker's skull, and ends at the upper beak/front head intersection while being surrounded by muscle along the whole length. A FE model of the hyoid apparatus was created based on the geometry, microstructure, and mechanical properties garnered from our experimental measurements. We compared the impact mitigation capabilities of the hyoid apparatus with an idealized straight cylinder and a tapered cylinder. The results showed that the hyoid geometry mitigated a greater amount of pressure and impulse compared to the straight or tapered cylinders. The initially applied longitudinal wave lost its strength from attenuation and conversion to transverse shear waves. This is due to the spiral curvature and tapered geometry, which induced lateral displacement in the hyoid bone. The lateral displacement of the bony hyoid induced strains on the adjacent muscle, where the energy dissipated due to the muscle's viscoelasticity. Quantitatively, as the stress wave traveled from the anterior to the posterior end of the hyoid apparatus, its pressure decreased 75% and the associated impulse decreased 84%. The analysis of the woodpecker's hyoid apparatus provides a novel perspective on impact mitigation mediated by a spiral-shaped structure and viscoelastic biocomposite.
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Bico/fisiologia , Materiais Biomiméticos , Osso Hioide/fisiologia , Passeriformes/fisiologia , Crânio/fisiologia , Estresse Fisiológico/fisiologia , Animais , Bico/anatomia & histologia , Fenômenos Biomecânicos/fisiologia , Dissecação/métodos , Dissecação/veterinária , Análise de Elementos Finitos , Osso Hioide/anatomia & histologia , Passeriformes/anatomia & histologia , Crânio/anatomia & histologiaRESUMO
Metallic tungsten (W) was initially assumed to be environmentally benign and a green alternative to lead. However, subsequent investigations showed that fishing weights and munitions containing elemental W can fragment and oxidize into complex monomeric and polymeric tungstate (WO4) species in the environment; this led to increased solubility and mobility in soils and increased bioaccumulation potential in plant and animal tissues. Here we expand on the results of our previous research, which examined tungsten toxicity, bioaccumulation, and compartmentalization into organisms, and present in this research that the bioaccumulation of W was related to greater than 50% reduction in the mechanical properties of the snail (Otala lactea), based on depth-sensing nanoindentation. Synchrotron-based X-ray fluorescence maps and X-ray diffraction measurements confirm the integration of W in newly formed layers of the shell matrix with the observed changes in shell biomechanical properties, mineralogical composition, and crystal orientation. With further development, this technology could be employed as a biomonitoring tool for historic metals contamination since unlike the more heavily studied bioaccumulation into soft tissue, shell tissue does not actively eliminate contaminants.
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Exoesqueleto/metabolismo , Monitoramento Ambiental/métodos , Gastrópodes/metabolismo , Fenômenos Mecânicos , Nanotecnologia/métodos , Tungstênio/metabolismo , Exoesqueleto/efeitos dos fármacos , Animais , Fenômenos Biomecânicos/efeitos dos fármacos , Dieta/efeitos adversos , Poluentes Ambientais/metabolismo , Poluentes Ambientais/toxicidade , Gastrópodes/anatomia & histologia , Gastrópodes/efeitos dos fármacos , Pele/efeitos dos fármacos , Pele/metabolismo , Tungstênio/toxicidadeRESUMO
Nanoscale ingredients in commercial products represent a point of emerging environmental concern due to recent findings that correlate toxicity with small particle size. A weight-of-evidence (WOE) approach based upon multiple lines of evidence (LOE) is developed here to assess nanomaterials as they exist in consumer product formulations, providing a qualitative assessment regarding the presence of nanomaterials, along with a baseline estimate of nanoparticle concentration if nanomaterials do exist. Electron microscopy, analytical separations, and X-ray detection methods were used to identify and characterize nanomaterials in sunscreen formulations. The WOE/LOE approach as applied to four commercial sunscreen products indicated that all four contained at least 10% dispersed primary particles having at least one dimension <100 nm in size. Analytical analyses confirmed that these constituents were comprised of zinc oxide (ZnO) or titanium dioxide (TiO2). The screening approaches developed herein offer a streamlined, facile means to identify potentially hazardous nanomaterial constituents with minimal abrasive processing of the raw material.
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Nanopartículas/análise , Queimadura Solar/prevenção & controle , Protetores Solares/química , Titânio/análise , Óxido de Zinco/análise , Humanos , Tamanho da PartículaRESUMO
In this study, the effects of microstructural inclusions on fatigue life of polyether ether ketone (PEEK) was investigated. Due to the versatility of its material properties, the semi-crystralline PEEK polymer has been increasingly adopted in a wide range of applications particularly as a biomaterial for orthopedic, trauma, and spinal implants. To obtain the cyclic behavior of PEEK, uniaxial fully-reversed strain-controlled fatigue tests were conducted at ambient temperature and at 0.02 mm/mm to 0.04 mm/mm strain amplitudes. The microstructure of PEEK was obtained using the optical and the scanning electron microscope (SEM) to determine the microstructural inclusion properties in PEEK specimen such as inclusion size, type, and nearest neighbor distance. SEM analysis was also conducted on the fracture surface of fatigue specimens to observe microstructural inclusions that served as the crack incubation sites. Based on the experimental strain-life results and the observed microstructure of fatigue specimens, a microstructure-sensitive fatigue model was used to predict the fatigue life of PEEK that includes both crack incubation and small crack growth regimes. Results show that the employed model is applicable to capture microstructural effects on fatigue behavior of PEEK.
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Cetonas/química , Fenômenos Mecânicos , Polietilenoglicóis/química , Benzofenonas , Teste de Materiais , Modelos Teóricos , Polímeros , Estresse MecânicoRESUMO
Gelatinous bone marrow transformation (GMT), also known as starvation marrow, represents a rare pathological entity of unclear etiology, in which bone marrow histopathology demonstrates hypoplasia, fat atrophy, and gelatinous infiltration. The finding of gelatinous marrow transformation lacks disease specificity; rather, it is an indicator of severe illness and a marker of poor nutritional status, found in patients with eating disorders, acute febrile illnesses, acquired immunodeficiency syndrome, alcoholism, malignancies, and congestive heart failure. We present a middle-aged woman with a history of alcoholism, depression, and anorexia nervosa who presented with failure to thrive and macrocytic anemia, with bone marrow examination demonstrative of gelatinous transformation, all of which resolved with appropriate treatment. To our knowledge, there are very few cases of GMT which have been successfully treated; thus, our case highlights the importance of proper supportive management.
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The interlinked fish scales of Atractosteus spatula (alligator gar) and Polypterus senegalus (gray and albino bichir) are effective multilayered armor systems for protecting fish from threats such as aggressive conspecific interactions or predation. Both types of fish scales have multi-layered structures with a harder and stiffer outer layer, and softer and more compliant inner layers. However, there are differences in relative layer thickness, property mismatch between layers, the property gradations and nanostructures in each layer. The fracture paths and patterns of both scales under microindentation loads were different. In this work, finite element models of fish scales of A. spatula and P. senegalus were built to investigate the mechanics of their multi-layered structures under penetration loads. The models simulate a rigid microindenter penetrating the fish scales quasi-statically to understand the observed experimental results. Study results indicate that the different fracture patterns and crack paths observed in the experiments were related to the different stress fields caused by the differences in layer thickness, and spatial distribution of the elastic and plastic properties in the layers, and the differences in interface properties. The parametric studies and experimental results suggest that smaller fish such as P. senegalus may have adopted a thinner outer layer for light-weighting and improved mobility, and meanwhile adopted higher strength and higher modulus at the outer layer, and stronger interface properties to prevent ring cracking and interface cracking, and larger fish such as A. spatula and Arapaima gigas have lower strength and lower modulus at the outer layers and weaker interface properties, but have adopted thicker outer layers to provide adequate protection against ring cracking and interface cracking, possibly because weight is less of a concern relative to the smaller fish such as P. senegalus.
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Modelos Biológicos , Pele/química , Estresse Mecânico , Animais , Análise de Elementos Finitos , PeixesRESUMO
The hierarchical architecture of protective biological materials such as mineralized fish scales, gastropod shells, ram's horn, antlers, and turtle shells provides unique design principles with potentials for guiding the design of protective materials and systems in the future. Understanding the structure-property relationships for these material systems at the microscale and nanoscale where failure initiates is essential. Currently, experimental techniques such as nanoindentation, X-ray CT, and SEM provide researchers with a way to correlate the mechanical behavior with hierarchical microstructures of these material systems1-6. However, a well-defined standard procedure for specimen preparation of mineralized biomaterials is not currently available. In this study, the methods for probing spatially correlated chemical, structural, and mechanical properties of the multilayered scale of A. spatula using nanoindentation, FTIR, SEM, with energy-dispersive X-ray (EDX) microanalysis, and X-ray CT are presented.
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Peixes/anatomia & histologia , Animais , Tegumento Comum/anatomia & histologia , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Relação Estrutura-Atividade , Tomografia Computadorizada por Raios XRESUMO
Although nanotechnology advancements should be fostered, the environmental health and safety (EHS) of nanoparticles used in technologies must be quantified simultaneously. However, most EHS studies assess the potential implications of the free nanoparticles which may not be directly applicable to the EHS of particles incorporated into in-use technologies. This investigation assessed the aquatic toxicological implications of copper oxide (CuO) nanospheres relative to CuO nanorods used in nanoenergetic applications to improve combustion. Particles were tested in both the as-received form and following combustion of a CuO/aluminum nanothermite. Results indicated nanospheres were more stable in water and slowly released ions, while higher surface area nanorods initially released more ions and were more toxic but generally less stable. After combustion, particles sintered into larger, micrometer-scale aggregates, which may lower toxicity potential to pelagic organisms due to deposition from water to sediment and reduced bioavailability after complexation with sediment organic matter. Whereas the larger nanothermite residues settled rapidly, implying lower persistence in water, their potential to release dissolved Cu was higher which led to greater toxicity to Ceriodaphnia dubia relative to parent CuO material (nanosphere or rod). This study illustrates the importance of considering the fate and toxicology of nanoparticles in context with their relevant in-use applications.