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151.
Jingwen Song Chengqian Yuan Tifeng Jiao Ruirui Xing Mengyao Yang Dave J. Adams Xuehai Yan 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(8)
There is a real need for new antibiotics against self‐evolving bacteria. One option is to use biofriendly broad‐spectrum and mechanically tunable antimicrobial hydrogels that can combat multidrug‐resistant microbes. Whilst appealing, there are currently limited options. Herein, broad‐spectrum antimicrobial biometallohydrogels based on the self‐assembly and local mineralization of Ag+‐coordinated Fmoc‐amino acids are reported. Such biometallohydrogels have the advantages of localized delivery and sustained release, reduced drug dosage and toxicity yet improved bioavailability, prolonged drug effect, and tunable mechanical strength. Furthermore, they can directly interact with the cell walls and membrane, resulting in the detachment of the plasma membrane and leakage of the cytoplasm. This leads to cell death, triggering a significant antibacterial effect against both Gram‐negative (Escherichia coli) and Gram‐positive (Staphylococcus aureus) bacteria in cells and mice. This study paves the way for developing a multifunctional integration platform based on simple biomolecules coordinated self‐assembly toward a broad range of biomedical applications. 相似文献
152.
Scott V. Jermain Dave Miller Angela Spangenberg Xingyu Lu Chaeho Moon Yongchao Su 《Drug development and industrial pharmacy》2019,45(5):724-735
KinetiSol® is a high-shear, fusion-based technology capable of producing stable amorphous solid dispersions (ASDs) without the assistance of solvent. KinetiSol® has proven successful with multiple challenging BCS class II and IV drugs, where drug properties like thermal instability or lack of appreciable solubility in volatile solvents make hot melt extrusion or spray drying unfeasible. However, there is a necessity to characterize the ASDs like those made by the KinetiSol® process, in order to better understand whether KinetiSol® is capable of homogeneously dispersing drug throughout a carrier in a short (<40?s) processing time. Our study utilized the high melting point, BCS class II drug, meloxicam, in order to evaluate the degree of homogeneity of 1, 5, and 10% w/w KinetiSol®-processed samples. Powder blend homogeneity and content uniformity were evaluated, and all samples demonstrated a meloxicam concentration % relative standard deviation of ≤2.0%. SEM/EDS was utilized to map elemental distribution of the processed samples, which confirmed KinetiSol®-processed materials were homogeneous at a 25 µm2 area. Utilizing Raman spectroscopy, we were able to verify the amorphous content of the processed samples. Finally, we utilized ssNMR 1?H spin-lattice relaxation measurement to evaluate the molecular miscibility of meloxicam with the polymer at 1% w/w drug load, for the first time, and determined the processed sample was highly miscible at ~200?nm scale. In conclusion, we determined the KinetiSol® process is capable of producing ASDs that are homogeneously and molecularly well-dispersed drug-in-polymer at drug concentrations as low as 1% w/w. 相似文献
153.
非磁性粘性颗粒在添加磁性大颗粒磁场流化床中的流化性能 总被引:3,自引:0,他引:3
通过添加磁性大颗粒,破碎活塞及沟流,显著改善了非磁性粘性颗粒在磁场流化床中的流化性能。为了评价非磁性粘性颗粒在磁场流化床中的流化性能,测量了最小流化速度、床层压力降和床膨胀高度。实验结果表明,非磁性粘性颗粒的最小流化速度,由于添加磁性大颗粒,而显著降低。磁性大颗粒添加量对非磁性粘性颗粒的最小流化速度有较大影响,随磁性大颗粒添加量的增加,最小流化速度降低,但当磁性大颗粒添加量增大到40%后,非磁性粘性颗粒和磁性大颗粒的混合物的最小流化速度就不再降低。 相似文献
154.
155.
Routine production or symbolic analysis? India and the globalisation of architectural services 总被引:1,自引:0,他引:1
Developments in information technology have reduced the need for spatial proximity in the geography of architectural employment: computer-based drafting allows for better standardisation and more efficient production of project information, whilst electronic communication links make the immediate transfer of this information possible across long distances. The ability to compress time and space may be paving the way to the relocation of architectural production facilities from higher-wage to lower-wage regions: numerous examples already exist of firms that have adopted this strategy to reduce their overheads.
Thus far, discussion of the viability and desirability of this emerging trend has been hampered by its close focus on the type of work carried out, and a consequently narrow view of its costs and benefits. Remote drafting is seen as a cheap form of professional north-south exploitation in architecture's intellectual circles that should be ignored if not deplored. By stressing the connection between the task and the culture in which it is developed, this paper seeks to produce a broader, alternative perspective, which identifies the several limitations of current off-shore collaborations but also points out possible future strengths, development strategies, and necessary environmental conditions.
The Indian context provides an opportunity to highlight analogies and differences between the recent growth of the export-oriented IT industry and the construction of a colonial professional practice at the turn of the twentieth century. If properly acknowledged by the domestic profession and considered by policy-makers, the development of a framework for distant architectural collaborations could be used not only to support the local design sector and bring the contested components of its post-colonial tradition in sharper focus and possibly closer together, but also to respond to the many challenges posed by the country's economic policies, growth, and infrastructural conditions. 相似文献
Thus far, discussion of the viability and desirability of this emerging trend has been hampered by its close focus on the type of work carried out, and a consequently narrow view of its costs and benefits. Remote drafting is seen as a cheap form of professional north-south exploitation in architecture's intellectual circles that should be ignored if not deplored. By stressing the connection between the task and the culture in which it is developed, this paper seeks to produce a broader, alternative perspective, which identifies the several limitations of current off-shore collaborations but also points out possible future strengths, development strategies, and necessary environmental conditions.
The Indian context provides an opportunity to highlight analogies and differences between the recent growth of the export-oriented IT industry and the construction of a colonial professional practice at the turn of the twentieth century. If properly acknowledged by the domestic profession and considered by policy-makers, the development of a framework for distant architectural collaborations could be used not only to support the local design sector and bring the contested components of its post-colonial tradition in sharper focus and possibly closer together, but also to respond to the many challenges posed by the country's economic policies, growth, and infrastructural conditions. 相似文献
156.
Most of the existing VANET routing protocols rely on information collected from beacons for making routing decisions such as next neighbor selection. Beacons are very small size hello messages that each vehicle broadcasts periodically. Owing to very small payload size of beacons as compared to the payload size of a data message, they can easily pass through even very weak links, through which a data message could never pass. Therefore, the use of beacon information for making routing decisions in a highly dynamic scenario such as VANETs may cause selection of routes through which data message can never be sent. Several researchers have given solutions that do not use beacon information for making routing decisions. But most of these solutions incorporate a large number of broadcasts to forward the data packets, causing wastage of bandwidth. In this paper, we present a beacon information independent geographic routing algorithm called BIIR, which reduces the number of broadcasts to forward the data packets by making intelligent use of information collected by the vehicle during previous route discovery attempts for a destination. Our simulation results have shown that the proposed algorithm outperforms the existing beacon less routing protocols in terms of the average number of broadcasts per data packet forwarding, packet delivery ratio and end to end delay experienced by the data messages. 相似文献
157.
Lee J Chen Q Zhang Q Reichard K Ditto D Mazurowski J Hackert M Yin S 《Applied optics》2007,46(28):6984-6989
We report laboratory test results of a long period grating (LPG) that can maintain a constant resonant peak depth over an enhanced tuning range when it is coated with an indium tin oxide (ITO) electrode that has optimized thickness and refractive index. The authors have experimentally demonstrated a LPG coated with ITO that can be tuned in excess of 200 nm with an ambient refractive index change of less than 0.01. To the best of the authors' knowledge, this is the highest sensitivity reported for a LPG to date. In addition to the tuning performance, the resonant peak remains within 1 dB of its maximum depth for at least 100 nm of the tuning range. 相似文献
158.
159.
160.
Ming-Ting Sun Dave Boyer Mike Lukacs 《International journal of imaging systems and technology》1997,8(5):427-431
With the growth of video conferencing, the need for multipoint conferences is also growing. In a multipoint videoconference over a wide-area network, the users are connected to a multipoint control unit (MCU) in a central office. A video bridge in the MCU combines the input video streams into a suitable format for presentation. In this article, we discuss various approaches of video bridging for continuous presence multipoint video conferencing. We also discuss the video quality issues and describe some multipoint video bridge prototypes we have developed. © 1997 John Wiley & Sons, Inc. Int J Imaging Syst Technol, 8, 427–431, 1997 相似文献