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1.
Ferroptosis is gaining followers as mechanism of selective killing cancer cells in a non-apoptotic manner, and novel nanosystems capable of inducing this iron-dependent death are being increasingly developed. Among them, polydopamine nanoparticles (PDA NPs) are arousing interest, since they have great capability of chelating iron. In this work, PDA NPs were loaded with Fe3+ at different pH values to assess the importance that the pH may have in determining their therapeutic activity and selectivity. In addition, doxorubicin was also loaded to the nanoparticles to achieve a synergist effect. The in vitro assays that were performed with the BT474 and HS5 cell lines showed that, when Fe3+ was adsorbed in PDA NPs at pH values close to which Fe(OH)3 begins to be formed, these nanoparticles had greater antitumor activity and selectivity despite having chelated a smaller amount of Fe3+. Otherwise, it was demonstrated that Fe3+ could be released in the late endo/lysosomes thanks to their acidic pH and their Ca2+ content, and that when Fe3+ was co-transported with doxorubicin, the therapeutic activity of PDA NPs was enhanced. Thus, reported PDA NPs loaded with both Fe3+ and doxorubicin may constitute a good approach to target breast tumors.  相似文献   
2.
The self‐assembly of specific polymers into well‐defined nanoparticles (NPs) is of great interest to the pharmaceutical industry as the resultant materials can act as drug delivery vehicles. In this work, a high‐throughput method to screen the ability of polymers to self‐assemble into NPs using a picoliter inkjet printer is presented. By dispensing polymer solutions in dimethyl sulfoxide (DMSO) from the printer into the wells of a 96‐well plate, containing water as an antisolvent, 50 suspensions are screened for nanoparticle formation rapidly using only nanoliters to microliters. A variety of polymer classes are used and in situ characterization of the submicroliter nanosuspensions shows that the particle size distributions match those of nanoparticles made from bulk suspensions. Dispensing organic polymer solutions into well plates via the printer is thus shown to be a reproducible and fast method for screening nanoparticle formation which uses two to three orders of magnitude less material than conventional techniques. Finally, a pilot study for a high‐throughput pipeline of nanoparticle production, physical property characterization, and cytocompatibility demonstrates the feasibility of the printing approach for screening of nanodrug delivery formulations. Nanoparticles are produced in the well plates, characterized for size and evaluated for effects on metabolic activity of lung cancer cells.  相似文献   
3.
To keep optimally connected, all electrolysis cell elements is one of the most important design criteria. The optimal distribution of the clamping points is crucial to increasing cell performance. In this work, the compression pressure distribution inside of a 25 cm2 PEM electrolysis cell was evaluated, using different materials: Teflon®, Viton®, ethylene propylene diene monomer rubber (EPDM), and nitrile rubber. Sealing material evaluation was performed taking as performance indicators: total compressed area (%) and compression pressure, for different torques applied. Pressure distribution was obtained by using pressure-sensitive films, analyzing the distribution of pressure points from three-dimensional plots (3D), and quantifying intensities of the images obtained. Results showed that pressure points distribution depends on the stiffness and thickness of the gasket materials. For a tightening torque of 3.70 N m, a pressure of 2.23 MPa is obtained with 85% of the membrane area compressed using nitrile rubber-EPDM gaskets.  相似文献   
4.
Nutritional research is currently entering the field of personalized nutrition, to a large extent driven by major technological breakthroughs in analytical sciences and biocomputing. An efficient launching of the personalized approach depends on the ability of researchers to comprehensively monitor and characterize interindividual variability in the activity of the human gastrointestinal tract. This information is currently not available in such a form. This review therefore aims at identifying and discussing published data, providing evidence on interindividual variability in the processing of the major nutrients, i.e., protein, fat, carbohydrates, vitamins, and minerals, along the gastrointestinal tract, including oral processing, intestinal digestion, and absorption. Although interindividual variability is not a primary endpoint of most studies identified, a significant number of publications provides a wealth of information on this topic for each category of nutrients. This knowledge remains fragmented, however, and understanding the clinical relevance of most of the interindividual responses to food ingestion described in this review remains unclear. In that regard, this review has identified a gap and sets the base for future research addressing the issue of the interindividual variability in the response of the human organism to the ingestion of foods.  相似文献   
5.
This study describes the hardware and software systems of the Micro Aerial Vehicle (MAV) platforms used by the ETH Zurich team in the 2017 Mohamed Bin Zayed International Robotics Challenge (MBZIRC). The aim was to develop robust outdoor platforms with the autonomous capabilities required for the competition, by applying and integrating knowledge from various fields, including computer vision, sensor fusion, optimal control, and probabilistic robotics. This paper presents the major components and structures of the system architectures and reports on experimental findings for the MAV‐based challenges in the competition. Main highlights include securing the second place both in the individual search, pick, and place the task of Challenge 3 and the Grand Challenge, with autonomous landing executed in less than 1 min and a visual servoing success rate of over for object pickups.  相似文献   
6.
Acetobacter pasteurianus, a member of the Alphaproteobacteria, is an acetic acid-producing bacterium present on sugar-rich substrates such as such as fruits, flowers and vegetables and traditionally used in the production of fermented food. The preferred living habitat associated with acid conditions makes the structure of the bacterial cell wall interesting to study, due to expected uncommon features. We have used a combination of chemical, analytical and NMR spectroscopy approaches to define the complete structure of the core oligosaccharide from A. pasteurianus CIP103108 LPS. Interestingly, the core oligosaccharide displays a high concentration of negatively charged groups, structural features that might contribute to reinforcing the bacterial membrane.  相似文献   
7.
8.
Wireless Personal Communications - The integration of everyday objects into the Internet represents the foundation of the forthcoming Internet of Things (IoT). Smart objects will be the building...  相似文献   
9.
The purpose of this paper is to present the structural design procedure of a low‐speed, horizontal axis, bio‐inspired wind turbine blade made of carbon/epoxy. The methodology initiates with the mechanical characterization of the carbon fiber composite material. An aerodynamic simulation using Computational Fluid Dynamics (CFD) method is performed in order to obtain the pressure distribution profile of the blade. This result is coupled with a Finite Element Analysis (FEA) to carry out an iterative design process through a Fluid‐Structure Interaction (FSI) simulation. Different stacking sequences of laminates are evaluated to find a configuration which allows balance between aerodynamic and dynamic inertial loads, ensuring an almost undeformed geometry during wind turbine's operation. The final structural design of the blade consists in six regions with different laminates. These are balanced and symmetric with distinct thickness characteristics and stacking sequences, which vary in three different orientations: 0°, ± 45° and 90°, achieving a minimum deflection at the tip close to 3.11 cm, and a total weight of 3.6 kg of a 1.8 m radius blade, even with the restrictions imposed by the non‐conventional geometry. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
10.
We report the monitoring of porous silicon (pSi) degradation in aqueous solutions using a consumer-grade digital camera. To facilitate optical monitoring, the pSi samples were prepared as one-dimensional photonic crystals (rugate filters) by electrochemical etching of highly doped p-type Si wafers using a periodic etch waveform. Two pSi formulations, representing chemistries relevant for self-reporting drug delivery applications, were tested: freshly etched pSi (fpSi) and fpSi coated with the biodegradable polymer chitosan (pSi-ch). Accelerated degradation of the samples in an ethanol-containing pH 10 aqueous basic buffer was monitored in situ by digital imaging with a consumer-grade digital camera with simultaneous optical reflectance spectrophotometric point measurements. As the nanostructured porous silicon matrix dissolved, a hypsochromic shift in the wavelength of the rugate reflectance peak resulted in visible color changes from red to green. While the H coordinate in the hue, saturation, and value (HSV) color space calculated using the as-acquired photographs was a good monitor of degradation at short times (t < 100 min), it was not a useful monitor of sample degradation at longer times since it was influenced by reflections of the broad spectral output of the lamp as well as from the narrow rugate reflectance band. A monotonic relationship was observed between the wavelength of the rugate reflectance peak and an H parameter value calculated from the average red-green-blue (RGB) values of each image by first independently normalizing each channel (R, G, and B) using their maximum and minimum value over the time course of the degradation process. Spectrophotometric measurements and digital image analysis using this H parameter gave consistent relative stabilities of the samples as fpSi > pSi-ch.  相似文献   
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