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1.
Rachel E. Pepper Emily E. Riley Matthieu Baron Thomas Hurot Lasse Tor Nielsen M. A. R. Koehl Thomas Kirboe Anders Andersen 《Journal of the Royal Society Interface》2021,18(175)
Microscopic sessile suspension feeders live attached to surfaces and, by consuming bacteria-sized prey and by being consumed, they form an important part of aquatic ecosystems. Their environmental impact is mediated by their feeding rate, which depends on a self-generated feeding current. The feeding rate has been hypothesized to be limited by recirculating eddies that cause the organisms to feed from water that is depleted of food particles. However, those results considered organisms in still water, while ambient flow is often present in their natural habitats. We show, using a point-force model, that even very slow ambient flow, with speed several orders of magnitude less than that of the self-generated feeding current, is sufficient to disrupt the eddies around perpendicular suspension feeders, providing a constant supply of food-rich water. However, the feeding rate decreases in external flow at a range of non-perpendicular orientations due to the formation of recirculation structures not seen in still water. We quantify the feeding flow and observe such recirculation experimentally for the suspension feeder Vorticella convallaria in external flows typical of streams and rivers. 相似文献
2.
Dr. Andrew M. Riley Dr. Sabine Windhorst Dr. Hong‐Yin Lin Prof. Barry V. L. Potter 《Chembiochem : a European journal of chemical biology》2014,15(1):57-67
When applied extracellularly, myo‐inositol hexakisphosphate (InsP6) and myo‐inositol pentakisphosphate (InsP5) can inhibit the growth and proliferation of tumour cells. There is debate about whether these effects result from interactions of InsP6 and InsP5 with intracellular or extracellular targets. We synthesised FAM‐InsP5, a fluorescent conjugate of InsP5 that allows direct visualisation of its interaction with cells. FAM‐InsP5 was internalised by H1229 tumour cells, a finding that supports earlier reports that externally applied inositol phosphates can—perhaps surprisingly—enter into cells. Close examination of the process of FAM‐InsP5 uptake suggests a mechanism of non‐receptor‐mediated endocytosis, which is blocked at 4 °C and probably involves interaction of the ligand with the glycocalyx. However, our results are difficult to reconcile with antiproliferative mechanisms that require direct interactions of externally applied InsP5 or InsP6 with cytosolic proteins, because internalised FAM‐InsP5 appears in lysosomes and apparently does not enter the cytoplasm. Studies using FAM‐InsP5 are less difficult and time‐consuming than experiments using InsP5 or InsP6, a factor that allowed us to analyse cellular uptake across a range of human cell types, identifying strong cell‐specific differences. 相似文献
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Gordon J. Kearley Veronica Gray Daniel P. Riley Oliver Kirstein Ramzi Kutteh Erich H. Kisi 《Journal of the American Ceramic Society》2014,97(3):916-922
Observed differences between measured and calculated elastic constants for Ti3SiC2 are investigated using Density Functional Theory and Inelastic Neutron Scattering. The agreement between the calculated lattice dynamics and the dynamics measured by inelastic neutron scattering is considered good except at energies below ~20 meV where discrepancies suggest anharmonic potentials. This suggestion is confirmed by Density Functional Theory—Molecular Dynamics simulation which shows multiple site occupancy of the Si atoms within the basal plane at finite temperature and produces a calculated inelastic spectrum in better agreement with the measured spectrum in the low‐energy region. The highly anharmonic potential energy surface of the Si atoms offers an explanation for the failure of elastic constants, calculated based on the harmonic approximation, to agree with initial experimental measurements. 相似文献
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Alex L. Riley Sarah E. Pepper Adam J. Canner Solomon F. Brown Mark D. Ogden 《分离科学与技术》2018,53(1):22-35
Work has been carried out screening hydrometallurgical resins for application in the valorization of industrially produced jarosite. Of the seven resins tested, anion exchange resins performed poorly for valuable metal recovery. Purolite S950+ and S957, along with a strong acid resin, show good extraction properties, but are selective for Fe3+ over the other (divalent) metals. Purolite S930+ (iminodiacetic acid-functionalized resin) demonstrates selectivity for Cu2+ over Fe3+, but poor selectivity for Ni2+, Zn2+, and Co2+. Dowex M4195 (bispicolylamine-functionalized resin) demonstrates promise for extracting metals of value away from a mixed metal pregnant liquor solution (PLS). A three-stage column-based recovery process is proposed for jarosite leachate treatment. 相似文献
7.
Atomic Layer Deposited Gallium Oxide Buffer Layer Enables 1.2 V Open‐Circuit Voltage in Cuprous Oxide Solar Cells 下载免费PDF全文
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Carolina Tallon Dorji Chavara Andrew Gillen Daniel Riley Lyndon Edwards Sam Moricca George V. Franks 《Journal of the American Ceramic Society》2013,96(8):2374-2381
Colloidal processing of the Ultra‐High Temperature Ceramic (UHTC) zirconium diboride (ZrB2) to develop near?net‐shaping techniques has been investigated. The use of the colloidal processing technique produces higher particle packing that ultimately enables achieving greater densification at lower temperatures and pressures, even pressureless sintering. ZrB2 suspension formulations have been optimized in terms of rheological behavior. Suspensions were shaped into green bodies (63% relative density) using slip casting. The densification was carried out at 1900°C, 2000°C, and 2100°C, using both hot pressing at 40 MPa and pressureless sintering. The colloidally processed materials were compared with materials prepared by a conventional dry processing route (cold pressed at 50 MPa) and subjected to the same densification procedures. Sintered densities for samples produced by the colloidal route are higher than produced by the dry route (up to 99.5% relative density by hot pressing), even when pressureless sintering is performed (more than 90% relative density). The promising results are considered as a starting point for the fabrication of complex‐shaped components that can be densified at lower sintering temperatures without pressure. 相似文献
10.
Sinem Korkmaz John I. Messner David R. Riley Christopher Magent 《Canadian Metallurgical Quarterly》2010,16(1):37-45
High-performance green buildings require close integration of building systems with a special focus on energy, daylighting, and material analysis during their design processes. Design process modeling and use of visualization tools can facilitate better communication and collaboration between team members; hence better integration in the design process. This paper presents a case study of the integrated design process of an Early Childhood Learning Center as performed by a team of university students and faculty. A process modeling approach of key decisions, required consultants, and virtual prototypes of the building was used during the design development stages of the case study. This case illustrates the use of process modeling and visualization tools to provide an accurate building information system for integrated teams. Through this experience, process modeling and visualization tools were found to be useful mechanisms to achieve high performance design goals and minimize design process waste. 相似文献