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Tolulope Joshua Ashaolu 《International Journal of Food Science & Technology》2021,56(8):3719-3725
Fervid interests on nanoparticles are increasing within the scientific and non-scientific communities, as they are utilised in food and non-food applications. The versatility of emerging applications of nanoparticles makes them potentially harmful to the food, healthcare and environment sectors, and thus necessitates the development of nanonutraceuticals from nutritional substances such as antioxidants, vitamins, fatty acids, fibres, probiotics and prebiotics. This review excavated state of the art on nanotechnology applications such as gold and selenium particles, nanolayers, nanobeads, nanoemulsions and nanofibers to probiotics and prebiotics for the synthesis of anticancer, antimicrobial, antioxidant and photo-reactive products among others, and finally delved into other noteworthy considerations like safety. It is concluded that available literature on the current status of nanoprobiotics and prebiotics are exhaustive, despite their huge potentials and applications. 相似文献
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Max J. Cotler Erin B. Rousseau Khalil B. Ramadi Joshua Fang Ann M. Graybiel Robert Langer Michael J. Cima 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(37)
Enhanced understanding of neuropathologies has created a need for more advanced tools. Current neural implants result in extensive glial scarring and are not able to highly localize drug delivery due to their size. Smaller implants reduce surgical trauma and improve spatial resolution, but such a reduction requires improvements in device design to enable accurate and chronic implantation in subcortical structures. Flexible needle steering techniques offer improved control over implant placement, but often require complex closed‐loop control for accurate implantation. This study reports the development of steerable microinvasive neural implants (S‐MINIs) constructed from borosilicate capillaries (OD = 60 µm, ID = 20 µm) that do not require closed‐loop guidance or guide tubes. S‐MINIs reduce glial scarring 3.5‐fold compared to prior implants. Bevel steered needles are utilized for open‐loop targeting of deep‐brain structures. This study demonstrates a sinusoidal relationship between implant bevel angle and the trajectory radius of curvature both in vitro and ex vivo. This relationship allows for bevel‐tipped capillaries to be steered to a target with an average error of 0.23 mm ± 0.19 without closed‐loop control. Polished microcapillaries present a new microinvasive tool for chronic, predictable targeting of pathophysiological structures without the need for closed‐loop feedback and complex imaging. 相似文献
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Silicon - This study focus on the effects of silicon inclusion carbonaceous particulate on the hardness and microstructural properties of carburized low carbon steel, at constant temperature of... 相似文献
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Russell C. Rockne Andrew D. Trister Joshua Jacobs Andrea J. Hawkins-Daarud Maxwell L. Neal Kristi Hendrickson Maciej M. Mrugala Jason K. Rockhill Paul Kinahan Kenneth A. Krohn Kristin R. Swanson 《Journal of the Royal Society Interface》2015,12(103)
Glioblastoma multiforme (GBM) is a highly invasive primary brain tumour that has poor prognosis despite aggressive treatment. A hallmark of these tumours is diffuse invasion into the surrounding brain, necessitating a multi-modal treatment approach, including surgery, radiation and chemotherapy. We have previously demonstrated the ability of our model to predict radiographic response immediately following radiation therapy in individual GBM patients using a simplified geometry of the brain and theoretical radiation dose. Using only two pre-treatment magnetic resonance imaging scans, we calculate net rates of proliferation and invasion as well as radiation sensitivity for a patient''s disease. Here, we present the application of our clinically targeted modelling approach to a single glioblastoma patient as a demonstration of our method. We apply our model in the full three-dimensional architecture of the brain to quantify the effects of regional resistance to radiation owing to hypoxia in vivo determined by [18F]-fluoromisonidazole positron emission tomography (FMISO-PET) and the patient-specific three-dimensional radiation treatment plan. Incorporation of hypoxia into our model with FMISO-PET increases the model–data agreement by an order of magnitude. This improvement was robust to our definition of hypoxia or the degree of radiation resistance quantified with the FMISO-PET image and our computational model, respectively. This work demonstrates a useful application of patient-specific modelling in personalized medicine and how mathematical modelling has the potential to unify multi-modality imaging and radiation treatment planning. 相似文献
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Timothy Zurrer Kenneth Wong Jonathan Horlyck Emma C. Lovell Joshua Wright Nicholas M. Bedford Zhaojun Han Kang Liang Jason Scott Rose Amal 《Advanced functional materials》2021,31(9):2007624
The vast chemical and structural tunability of metal–organic frameworks (MOFs) are beginning to be harnessed as functional supports for catalytic nanoparticles spanning a range of applications. However, a lack of straightforward methods for producing nanoparticle-encapsulated MOFs as efficient heterogeneous catalysts limits their usage. Herein, a mixed-metal MOF, NiMg-MOF-74, is utilized as a template to disperse small Ni nanoclusters throughout the parent MOF. By exploiting the difference in Ni O and Mg O coordination bond strength, Ni2+ is selectively reduced to form highly dispersed Ni nanoclusters constrained by the parent MOF pore diameter, while Mg2+ remains coordinated in the framework. By varying the ratio of Ni to Mg in the parent MOF, accessible surface area and crystallinity can be tuned upon thermal treatment, influencing CO2 adsorption capacity and hydrogenation selectivity. The resulting Ni nanoclusters prove to be an active catalyst for CO2 methanation and are examined using extended X-ray absorption fine structure and X-ray photoelectron spectroscopy. By preserving a segment of the Mg2+-containing MOF framework, the composite system retains a portion of its CO2 adsorption capacity while continuing to deliver catalytic activity. The approach is thus critical for designing materials that can bridge the gap between carbon capture and CO2 utilization. 相似文献
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Dams disrupt the flow of water and sediment and thus have the potential to affect the downstream geomorphic characteristics of a river. Though there are some well‐known and common geomorphic responses to dams, such as bed armouring, the response downstream from any particular dam is dependent on local conditions. Herein, we investigate the response of the upper Santa Ana River in southern California, USA, to the construction of a large dam at the transition from mountains to valley, using calculations of bedload transport capacity on the mainstem below the dam and for major tributaries. Approximate sediment budgets were constructed for downstream reaches to estimate deposition and erosion rates for sand, gravel, and cobble particle sizes. Our results indicate that the classical response of bed armouring and erosion is likely limited to a short reach immediately below the dam. Farther downstream, though transport capacity is reduced by flow regulation by the dam, the channel reaches are likely to remain depositional but with reduced deposition rates. Persistent deposition, as opposed to erosion, is the result of the replenishment of flow and sediment supply by large downstream tributaries. In addition, the calculations indicate that the composition of the bed is unlikely to change substantially in downstream reaches. A Monte Carlo approach was employed to estimate the uncertainty in the sediment budget predictions. The impacts of the dam on the geomorphic character of the river downstream could have implications for native fish that rely on coarse substrate that supports their food base. 相似文献
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Joshua C. Price Simon J. Levett Valentin Radu David A. Simpson Aina Mogas Barcons Christopher F. Adams Melissa L. Mather 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(22)
Fluorescent nanodiamonds (fNDs) containing nitrogen vacancy (NV) centers are promising candidates for quantum sensing in biological environments. This work describes the fabrication and implementation of electrospun poly lactic‐co‐glycolic acid (PLGA) nanofibers embedded with fNDs for optical quantum sensing in an environment, which recapitulates the nanoscale architecture and topography of the cell niche. A protocol that produces uniformly dispersed fNDs within electrospun nanofibers is demonstrated and the resulting fibers are characterized using fluorescent microscopy and scanning electron microscopy (SEM). Optically detected magnetic resonance (ODMR) and longitudinal spin relaxometry results for fNDs and embedded fNDs are compared. A new approach for fast detection of time varying magnetic fields external to the fND embedded nanofibers is demonstrated. ODMR spectra are successfully acquired from a culture of live differentiated neural stem cells functioning as a connected neural network grown on fND embedded nanofibers. This work advances the current state of the art in quantum sensing by providing a versatile sensing platform that can be tailored to produce physiological‐like cell niches to replicate biologically relevant growth environments and fast measurement protocols for the detection of co‐ordinated endogenous signals from clinically relevant populations of electrically active neuronal circuits. 相似文献
10.
Hammons Joshua A. Tumey Scott J. Idell Yaakov Jeffries Jason R. 《JOM Journal of the Minerals, Metals and Materials Society》2020,72(1):176-186
JOM - Alpha-radiation damage in metals is a concern for long-term radioactive storage and systems that produce nuclear energy. Accurate prediction of irradiated material properties and failure... 相似文献