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1.
Dr. Liam J. Stephens Dr. Aviva Levina Dr. Iman Trinh Dr. Victoria L. Blair Dr. Melissa V. Werrett Prof. Peter A. Lay Prof. Philip C. Andrews 《Chembiochem : a European journal of chemical biology》2020,21(8):1188-1200
RuII-arene complexes provide a versatile scaffold for novel anticancer drugs. Seven new RuII-arene-thiocarboxylato dimers were synthesized and characterized. Three of the complexes ( 2 a , b and 5 ) showed promising antiproliferative activities in MDA-MB-231 (human invasive breast cancer) cells, and were further tested in a panel of fifteen cancerous and noncancerous cell lines. Complex 5 showed moderate but remarkably selective activity in MDA-MB-231 cells (IC50=39±4 μm Ru). Real-time proliferation studies showed that 5 induced apoptosis in MDA-MB-231 cells but had no effect in A549 (human lung cancer, epithelial) cells. By contrast, 2 a and b showed moderate antiproliferative activity, but no apoptosis, in either cell line. Selective cytotoxicity of 5 in aggressive, mesenchymal-like MDA-MB-231 cells over many common epithelial cancer cell lines (including noninvasive breast cancer MCF-7) makes it an attractive lead compound for the development of specifically antimetastatic Ru complexes with low systemic toxicity. 相似文献
2.
Koay Seong Chun Chan Ming Yeng Chou Pui May Tshai Kim Yeow Ong Thai Kiat Cheah Kean How 《乙烯基与添加剂工艺杂志》2020,26(1):10-16
Chrysanthemum flower is among one of the highly sought after and widely planted flower crops, in particular for cultural and religious ceremonies. However, the chrysanthemum stem and stalk have little value and usually discard as by‐product waste from floristry. The objective of this research is to investigate the potential value of utilizing chrysanthemum stem and stalk as reinforcing fillers for thermoplastic composites. In this study, 2‐mm thick composite sheet containing predefined formulations of polylactic acid (PLA), chrysanthemum waste filler (CWF) ranging from 15 to 60 phr, and maleated polyethylene (MAPE) coupling agent up to 5 phr were prepared with the aid of Haake internal mixer and compression molding. The effect of MAPE loading on tensile, thermal, and morphological properties of PLA/CWF composites was investigated. The findings revealed that PLA/CWF composite attained improved tensile modulus compared to the neat PLA, and the tensile modulus increases with higher concentration of CWF. However, both tensile strength and elongation at break reduces with increase loading of CWF. Overall, PLA/CWF composites with MAPE shows better performance compared to those without MAPE, where an optimum strength of 21.8 MPa can be achieved with 60 phr CW and 3 phr MAPE. The measured tensile strength is comparable to alternatives natural fiber thermoplastic composites demonstrating its potential to be used in non‐structurally demanding application. J. VINYL ADDIT. TECHNOL., 26:10–16, 2020. © 2019 Society of Plastics Engineers 相似文献
3.
Harry Charalambous Shikhar Krishn Jha Kent Harrison Christian Ryan Thomas Lay Thomas Tsakalakos 《Journal of the European Ceramic Society》2018,38(10):3689-3693
In conventional flash sintering, the current rises nonlinearly to a set current limit, accompanied by a spike in the power density. This sudden power spike may cause hot spot formation, in which current preferentially channels through a small area, causing localized melting while other areas remain unsintered. By using a controlled current ramp early on the sudden power spike can be avoided. In addition, by changing the ramp rate material properties such as porosity, grain size and conductivity can be tuned. 相似文献
4.
Husain Syed Sameed Ong Eng-Jon Bober Miroslaw 《International Journal of Computer Vision》2021,129(5):1432-1450
International Journal of Computer Vision - We propose a novel CNN architecture called ACTNET for robust instance image retrieval from large-scale datasets. Our key innovation is a learnable... 相似文献
5.
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
6.
This paper uses a wet-chemical precipitation route to prepare radical-shaped ZnO microprisms and to deposit Cerium oxide (CeO2) on the surface of ZnO, to form CeO2/ZnO microstructures. The samples are characterized using X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and UV–vis diffuse reflectance spectroscopy. Their catalytic activity is also evaluated using methylene blue (MB) as a detection reagent. CeO2/ZnO systems exhibit higher UV absorption and transparency in the visible region. The experimental results show that the deposition of CeO2 nanospecies is successful and that the radical-shaped microstructures of ZnO are well maintained. The CeO2/ZnO microstructures exhibit a much greater intensity of UV-light absorptivity and much higher photocatalytic activity than those of radical-shaped ZnO microprisms. 相似文献
7.
Teen Hang Meen Jenn Kai Tsai Yu Shin Tu Tian Chiuan Wu Wen Dung Hsu Shoou-Jinn Chang 《Nanoscale research letters》2014,9(1):523
In this study, the P25 titanium dioxide (TiO2) nanoparticle (NP) thin film was coated on the fluorine-doped tin oxide (FTO) glass substrate by a doctor blade method. The film then compressed mechanically to be the photoanode of dye-sensitized solar cells (DSSCs). Various compression pressures on TiO2 NP film were tested to optimize the performance of DSSCs. The mechanical compression reduces TiO2 inter-particle distance improving the electron transport efficiency. The UV–vis spectrophotometer and electrochemical impedance spectroscopy (EIS) were employed to quantify the light-harvesting efficiency and the charge transport impedance at various interfaces in DSSC, respectively. The incident photon-to-current conversion efficiency was also monitored. The results show that when the DSSC fabricated by the TiO2 NP thin film compressed at pressure of 279 kg/cm2, the minimum resistance of 9.38 Ω at dye/TiO2 NP/electrolyte interfaces, the maximum short-circuit photocurrent density of 15.11 mA/cm2, and the photoelectric conversion efficiency of 5.94% were observed. Compared to the DSSC fabricated by the non-compression of TiO2 NP thin film, the overall conversion efficiency is improved over 19.5%. The study proves that under suitable compression pressure the performance of DSSC can be optimized. 相似文献
8.
A new method for characterizing denitrifying phosphorus removal bacteria by using three different types of electron acceptors 总被引:57,自引:0,他引:57
This study investigated the characteristics of denitrifying phosphorus removal bacteria by using three different types of electron acceptors as well as the positive role of nitrite in phosphorus removal process. Denitrifying phosphorous removal bacteria was enriched under anaerobic-anoxic (A/A) condition. To understand A/A sludge better, sludge from two other sources were also studied. These include sludges obtained from a lab-scale anaerobic-anoxic-aerobic (A/A/O) system and a local sewage treatment plant. Three types of possible electron acceptors (oxygen, nitrate and nitrite) were examined for their roles in phosphorus uptake. The results obtained indicated that oxygen, nitrate and nitrite were able to act as electron acceptors successfully. This observation suggested that in addition to the two well-accepted groups of phosphorus removal bacteria (one can only utilize oxygen to take up phosphorus, P(O), while the other can use both oxygen and nitrate, P(ON)), a new group of phosphorus removal bacteria, P(ON(n)), which could use oxygen, nitrate or nitrite to take up phosphorus was identified. The relative population of these three types of bacteria could be calculated from results obtainable from phosphorus uptake batch experiments with either oxygen or nitrate or nitrite as electron acceptor. The results obtained in this study showed that A/A sludge had similar phosphorus removal performance as the A/A/O sludge. However, it has better denitrifying phosphorus removal capability, which was demonstrated by the relative population of the three groups of bacteria. The results also suggested that nitrite was not an inhibitor to phosphorus removal process. Instead, it is an alternative electron acceptor to oxygen or nitrate. 相似文献
9.
Investigation of assimilable organic carbon (AOC) and bacterial regrowth in drinking water distribution system 总被引:13,自引:0,他引:13
This paper investigated the variation of assimilable organic carbon (AOC) concentrations in water from several typical water treatment plants and distribution systems in a northern city of China. It is concluded from this study that: (1) The AOC in most of the product water of the studied water treatment plants and the water from the associated distribution systems could not meet the biostability criteria of 50-100 microg/L. (2) Only 4% of the measured AOC concentrations were less than 100 microg/L. However, about half of the measured AOC values were less than 200 microg/L. (3) Better source water quality resulted in lower AOC concentrations. (4) The variation of AOC concentrations in distribution systems was affected by chlorine oxidation and bacterial activity: the former resulted in an increase of AOC value while the latter led to a reduction in AOC. (5) The variation of AOC concentration followed different patterns in different distribution systems or different seasons due to their respective operational characteristics. (6) Less than 30% of AOC could be removed by a conventional treatment process, whereas 30-60% with a maximum of 50-60% could be removed by granular activated carbon (GAC). (7) The observation via scanning electron microscope (SEM) on distribution pipe tubercle samples demonstrated that the pipe inner wall was not smooth and bacteria multiplied in the crevice as well as in the interior wall of distribution pipes. 相似文献
10.
Studies on the respiratory health of primary school children in urban communities of Hong Kong 总被引:3,自引:0,他引:3
S G Ong J Liu C M Wong T H Lam A Y Tam L Daniel A J Hedley 《The Science of the total environment》1991,106(1-2):121-135
The first stage of a 2-year survey of respiratory morbidity in primary school children was conducted in two districts of Hong Kong in April/May 1989. One group (2009) of children was from Kwai Tsing District, which had high levels of exhaust emission from factories. The other group (1837) was from Southern District where atmospheric pollution was considered to be relatively low. After adjustment for gender, age, socioeconomic factors, child smoking and exposure to parental smoking, the prevalence ratios of sore throat, evening cough, cough for more than 3 months, morning phlegm and wheezing were found to be significantly higher in Kwai Tsing. The difference between the districts is likely to be related to the environmental air quality. The study, which is continuing, will provide the basis for an evaluation of the impact of new low sulphur fuel regulations introduced in July 1990. 相似文献