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Microfluidic fluorescence‐activated cell sorters (μFACS) have attracted considerable interest because of their ability to identify and separate cells in inexpensive and biosafe ways. Here a high‐performance μFACS is presented by integrating a standing surface acoustic wave (SSAW)‐based, 3D cell‐focusing unit, an in‐plane fluorescent detection unit, and an SSAW‐based cell‐deflection unit on a single chip. Without using sheath flow or precise flow rate control, the SSAW‐based cell‐focusing technique can focus cells into a single file at a designated position. The tight focusing of cells enables an in‐plane‐integrated optical detection system to accurately distinguish individual cells of interest. In the acoustic‐based cell‐deflection unit, a focused interdigital transducer design is utilized to deflect cells from the focused stream within a minimized area, resulting in a high‐throughput sorting ability. Each unit is experimentally characterized, respectively, and the integrated SSAW‐based FACS is used to sort mammalian cells (HeLa) at different throughputs. A sorting purity of greater than 90% is achieved at a throughput of 2500 events s?1. The SSAW‐based FACS is efficient, fast, biosafe, biocompatible and has a small footprint, making it a competitive alternative to more expensive, bulkier traditional FACS.  相似文献   
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A boronic acid-based anthracene fluorescent probe was functionalised with an acrylamide unit to incorporate into a hydrogel system for monosaccharide detection. In solution, the fluorescent probe displayed a strong fluorescence turn-on response upon exposure to fructose, and an expected trend in apparent binding constants, as judged by a fluorescence response where D-fructose>D-galactose>D-mannose>D-glucose. The hydrogel incorporating the boronic acid monomer demonstrated the ability to detect monosaccharides by fluorescence with the same overall trend as the monomer in solution with the addition of D-fructose resulting in a 10-fold enhancement (≤0.25 mol/L).  相似文献   
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Microbial growth and fluctuations in environmental conditions have been shown to cause microbial contamination and deterioration of food. Thus, it is paramount to develop reliable strategies to effectively prevent the sale and consumption of contaminated or spoiled food. Responsive packaging systems are designed to react to specific stimuli in the food or environment, such as microorganisms or temperature, then implement an informational or corrective response. Informative responsive packaging is aimed at continuously monitoring the changes in food or environmental conditions and conveys this information to the users in real time. Meanwhile, packaging systems with the capacity to control contamination or deterioration are also of great interest. Encouragingly, corrective responsive packaging attempting to mitigate the adverse effects of condition fluctuations on food has been investigated. This packaging exerts its effects through the triggered release of active agents by environmental stimuli. In this review, informative and corrective responsive packaging is conceptualized clearly and concisely. The mechanism and characteristics of each type of packaging are discussed in depth. This review also summarized the latest research progress of responsive packaging and objectively appraised their advantages. Evidently, the mechanism through which packaging systems respond to microbial contamination and associated environmental factors was also highlighted. Moreover, risk concerns, related legislation, and consumer perspective in the application of responsive packaging are discussed as well. Broadly, this comprehensive review covering the latest information on responsive packaging aims to provide a timely reference for scientific research and offer guidance for presenting their applications in food industry.  相似文献   
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Journal of Mathematical Imaging and Vision - The ability to handle large scale variations is crucial for many real-world visual tasks. A straightforward approach for handling scale in a deep...  相似文献   
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Public housing is one of few sources of low‐income rental housing in inner‐city Melbourne, Australia. Most of this housing is easily identifiable high‐rise estates. Some of these estates have become established centres of heroin dealing and drug use. This has had significant consequences: applicants reject offers of housing on the estates; tenants apply for transfers; and housing officers face workplace occupational health and safety issues. In sum, the presence of the drug trade is undermining the provision of affordable, well‐located public housing. This paper contributes to discussions that seek to restore the value of this common resource. It does so by drawing on qualitative interviews and focus groups conducted with heroin users who live in and/or use public housing. The experience of these individuals gives insight into the current relationship between the illicit drug trade and public housing, as well as some understanding of the resilience of the illicit drug trade. The paper looks at measures that have been implemented to address this problem, before questioning whether there is room for an innovative, regulatory response to illicit drug use.  相似文献   
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ABSTRACT

Many planning agencies worldwide now see climate change response as unavoidable. This paper proposes that a central task for contemporary planning theory is to guide planning practice as it develops multi-dimensional responses. We examine three theoretical constructs: anticipatory governance, legitimacy and social-ecological resilience. We argue that each conceptualises challenges climate change presents to planning practice, while providing theoretically informed options for responses. Building on this, we utilize Friedmann’s [2008. “The Uses of Planning Theory: A Bibliographic Essay.” Journal of Planning Education and Research 28 (2): 247–257. doi:10.1177/0739456X08325220] tasks for planning theory as a framework to assess the utility of planning theories to guide climate change response through practice. Associated issues are discussed, including the influence of translatable planning theories and the value of importing knowledge from other disciplines. The paper concludes that more sophisticated interplay between planning theory and practice may improve planning responses to the climate change threat. The need for planning theory to translate its conceptual discoveries to the domain of practice is key.  相似文献   
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