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991.
Daniel Boon Loong Teh Akshaya Bansal Chou Chai Tan Boon Toh Robert Alan Jappy Tucker Gil Gerald Lasam Gammad Yanzhuang Yeo Zhendong Lei Xiang Zheng Fengyuan Yang John S. Ho Nagarjun Bolem Bing Cheng Wu Muthu Kumar Gnanasammandhan Lissa Hooi Gavin Stewart Dawe Camilo Libedinsky Wei-Yi Ong Barry Halliwell Edward Kai-Hua Chow Kah-Leong Lim Yong Zhang Brian K. Kennedy 《Advanced materials (Deerfield Beach, Fla.)》2020,32(29):2001459
Near-infrared (NIR) activatable upconversion nanoparticles (UCNPs) enable wireless-based phototherapies by converting deep-tissue-penetrating NIR to visible light. UCNPs are therefore ideal as wireless transducers for photodynamic therapy (PDT) of deep-sited tumors. However, the retention of unsequestered UCNPs in tissue with minimal options for removal limits their clinical translation. To address this shortcoming, biocompatible UCNPs implants are developed to deliver upconversion photonic properties in a flexible, optical guide design. To enhance its translatability, the UCNPs implant is constructed with an FDA-approved poly(ethylene glycol) diacrylate (PEGDA) core clad with fluorinated ethylene propylene (FEP). The emission spectrum of the UCNPs implant can be tuned to overlap with the absorption spectra of the clinically relevant photosensitizer, 5-aminolevulinic acid (5-ALA). The UCNPs implant can wirelessly transmit upconverted visible light till 8 cm in length and in a bendable manner even when implanted underneath the skin or scalp. With this system, it is demonstrated that NIR-based chronic PDT is achievable in an untethered and noninvasive manner in a mouse xenograft glioblastoma multiforme (GBM) model. It is postulated that such encapsulated UCNPs implants represent a translational shift for wireless deep-tissue phototherapy by enabling sequestration of UCNPs without compromising wireless deep-tissue light delivery. 相似文献
992.
Yeon Ui Lee Kanghoon Yim Steven Edward Bopp Junxiang Zhao Zhaowei Liu 《Advanced materials (Deerfield Beach, Fla.)》2020,32(28):2002387
Hyperbolic media strengthen numerous attractive applications in optics such as super-resolution imaging, enhanced spontaneous emission, and nanoscale waveguiding. Natural hyperbolic materials exist at visible frequencies; however, implementations of these materials suffer substantial compromises resulting from the high loss in the currently available candidates. Here, the first experimental and theoretical investigation of regioregular poly(3-alkylthiophenes) (rr-P3ATs), a naturally low-loss organic hyperbolic material (OHM) in the visible frequency range, is shown. These hyperbolic properties arise from a highly ordered structure of layered electron-rich conjugated thiophene ring backbones separated by insulating alkyl side chains. The optical and electronic properties of the rr-P3AT can be tuned by controlling the degree of crystallinity and alkyl side chain length. First-principles calculations support the experimental observations, which result from the rr-P3AT's structural and optical anisotropy. Conveniently, rr-P3AT-based OHMs are facile to fabricate, flexible, and biocompatible, which may lead to tremendous new opportunities in a wide range of applications. 相似文献
993.
In this age of public skepticism about science, sustainability science offers a way to increase the application of science in planning and policy. This paper explores the relationship between science and society and the emergence of sustainability science. A comparison of the theory and practice of sustainability science and planning reveals the potential for a natural partnership. Based on the analysis, I suggest ways that planning may bridge the gap and build on the opportunity to strengthen its purpose and impact. 相似文献
994.
Dr. Vladimir O. Talibov Dr. Edoardo Fabini Edward A. FitzGerald Dr. Daniele Tedesco Daniela Cederfeldt Martin J. Talu Moira M. Rachman Filip Mihalic Dr. Elisabetta Manoni Dr. Marina Naldi Dr. Paola Sanese Dr. Giovanna Forte Dr. Martina Lepore Signorile Prof. Xavier Barril Dr. Cristiano Simone Prof. Manuela Bartolini Dr. Doreen Dobritzsch Dr. Alberto Del Rio Prof. U. Helena Danielson 《Chembiochem : a European journal of chemical biology》2021,22(9):1597-1608
SMYD3 is a multifunctional epigenetic enzyme with lysine methyltransferase activity and various interaction partners. It is implicated in the pathophysiology of cancers but with an unclear mechanism. To discover tool compounds for clarifying its biochemistry and potential as a therapeutic target, a set of drug-like compounds was screened in a biosensor-based competition assay. Diperodon was identified as an allosteric ligand; its R and S enantiomers were isolated, and their affinities to SMYD3 were determined (KD=42 and 84 μM, respectively). Co-crystallization revealed that both enantiomers bind to a previously unidentified allosteric site in the C-terminal protein binding domain, consistent with its weak inhibitory effect. No competition between diperodon and HSP90 (a known SMYD3 interaction partner) was observed although SMYD3–HSP90 binding was confirmed (KD=13 μM). Diperodon clearly represents a novel starting point for the design of tool compounds interacting with a druggable allosteric site, suitable for the exploration of noncatalytic SMYD3 functions and therapeutics with new mechanisms of action. 相似文献
995.
Meysam Heydari Gharahcheshmeh Maxwell T. Robinson Edward F. Gleason Karen K. Gleason 《Advanced functional materials》2021,31(14):2008712
Engineering the texture and nanostructure to improve the electrical conductivity of semicrystalline conjugated polymers must address the rate-limiting step for charge carrier transport. In highly face-on orientation, the charge transport between chains within a crystallite becomes rate-limiting, which is highly sensitive to the π–π stacking distance and interchain charge transfer integral. Here, face-on oriented semicrystalline poly(3,4-ethylenedioxythiophene) (PEDOT) thin films are grown via water-assisted (W-A) oxidative chemical vapor deposition (oCVD). Combining W-A with the volatile oxidant, antimony pentachloride, yields an optimized electrical conductivity of 7520 ± 240 S cm−1, a record for PEDOT thin films. Systematic control of π–π stacking distance from 3.50 Å down to 3.43 Å yields an electrical conductivity enhancement of ≈ 1140%. The highest electrical conductivity also corresponds to minimum in Urbach energy of 205 meV, indicating superior morphological order. The figure of merit for transparent conductors, σdc/σop, reaches a maximum value of 94, which is 1.9 × and 6.7 × higher than oCVD PEDOT grown without W-A and utilizing vanadium oxytrichloride and iron chloride oxidizing agents, respectively. The W-A oCVD is single-step all-dry process and provides conformal coverage, allowing direct growth on mechanical flexible, rough, and structured surfaces without the need for complex and costly transfer steps. 相似文献
996.
Ric Hoefnagels Edward Smeets André Faaij 《Renewable & Sustainable Energy Reviews》2010,14(7):1661-1694
The aim of this study is to show the impact of different assumptions and methodological choices on the life-cycle greenhouse gas (GHG) performance of biofuels by providing the results for different key parameters on a consistent basis. These include co-products allocation or system expansion, N2O emissions from crop cultivation, conversion systems and co-product applications and direct land-use change emissions. The results show that the GHG performance of biofuels varies depending on the method applied and the system boundaries selected. Key factors include selected allocation procedures and the location of production and related yields, reference land and soil N2O emissions. 相似文献
997.
Aishwarya Srivastava Siddhant Aggarwal Amy Apon Edward Duffy Ken Kennedy Andre Luckow Brandon Posey Marcin Ziolkowski 《Software》2020,50(6):868-898
We investigate the challenges of building an end-to-end cloud pipeline for real-time intelligent visual inspection system for use in automotive manufacturing. Current methods of visual detection in automotive assembly are highly labor intensive, and thus prone to errors. An automated process is sought that can operate within the real-time constraints of the assembly line and can reduce errors. Components of the cloud pipeline include capture of a large set of high-definition images from a camera setup at the assembly location, transfer and storage of the images as needed, execution of object detection, and notification to a human operator when a fault is detected. The end-to-end execution must complete within a fixed time frame before the next car arrives in the assembly line. In this article, we report the design, development, and experimental evaluation of the tradeoffs of performance, accuracy, and scalability for a cloud system. 相似文献
998.
999.
Edward A. Chappell 《Vernacular Architecture》2018,49(1):79-98
Early-modern timber framing and associated finish vary significantly among the countless places settled by Europeans and Africans in the age of exploration. Most of these dots on maps of the western hemisphere remain essentially unstudied, as evidence for their vernacular architecture slips away. This is of more than local interest because the material offers opportunities to investigate how related populations share and alter cultural traits, and how the traits evolve in response to degrees of immigration, value of labour, environmental conditions and trade. This paper focuses on one of the dots, presenting new evidence for frame construction on the small British island of Bermuda, and addresses its role in the population’s economic evolution. 相似文献
1000.
Marcin Górny Edward Tyrała Gabriela Sikora Łukasz Rogal 《Metals and Materials International》2018,24(1):95-100
In the present work, the Mg2Cu precipitates in copper-alloyed austempered ductile iron (ADI) were identified by analyzing techniques such as TEM and SEM with EDS. It was revealed that, in castings made of ADI-containing copper, highly dispersed particles of Mg2Cu are formed, whose size does not exceed <1 μm. The research work was carried out on ductile iron that was austenitized at 900 °C, followed by austempering at 380 °C. The microstructure was investigated using various techniques, including optical microscopy, XRD, SEM, and TEM. In addition to this, the exhibited impact properties of castings with Cu, Ni, and Cu+Ni were also determined. This study casts a new light on the formation of the structure of Cu-alloyed ADI. The highly-dispersive and brittle Mg2Cu particles that are located in the vicinity of the graphite nodules have a negative effect on the impact properties of ADI. It has also been shown that impact strength decreases from levels of 160-180 J (for copper-free ADI) to 90-120 J (for copper-and copper-nickel-alloyed ADI). 相似文献