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51.
Gautam Mishra Christopher D. Easton Gregory J.S. Fowler Sally L. McArthur 《Polymer》2011,52(9):1882-1890
A combination of spontaneous reactive chemical domains bounded by non-fouling zones provides a means to covalently immobilize biomolecules in structured, spatially defined arrays. These arrays have application in a wide range of biotechnologies including tissue engineering, proteomics, and diagnostics. In this paper, we describe the fabrication of multi-chemistry micropatterns from plasma polymers. X-ray photoelectron spectroscopy (XPS), together with Time-of-Flight Static Secondary Ion Mass Spectrometry (ToF-SSIMS) and confocal imaging has been utilized to confirm the reactivity and integrity of micropatterns fabricated from amine-reactive maleic anhydride (ppMA) on non-fouling tetraglyme (ppTg). The covalent immobilization of antibodies via the formation of amide linkages with the anhydride groups occurs only in the ppMA domains, while antibody activity is confirmed via their ability to attract specific fluorescent antigens. These micropatterns therefore provide a convenient and effective platform for covalently immobilizing biomolecules in spatially defined areas without the need for multiple step wet chemical immobilization strategies. 相似文献
52.
Eight samples of brachiopod shell material have been analyzed for their strontium isotope composition in order to more accurately date Lower to Upper Permian siliceous biogenic strata of Spitsbergen (Kapp Starostin Formation) and the southern Barents Sea (Røye Formation). The results are interpreted as showing a mid-Artinskian age for the basal Vøringen Member of the Kapp Starostin Formation and a range of late Artinskian to Roadian for the overlying part of this unit. The upper part of the Røye Formation yields ages in the range Roadian to Wuchiapingian. These results are consistent with available biostratigraphic data and confirm the potential of strontium isotope stratigraphy for developing a more accurate chronology of the widespread spiculite deposits that characterize the northern margin of Pangea in late-Early Permian to Late Permian time and which constitute a potential target for petroleum exploration. 相似文献
53.
COMMAS (COndition Monitoring Multi-Agent System) 总被引:3,自引:0,他引:3
Mangina E. E. McArthur S. D. J. McDonald J. R. 《Autonomous Agents and Multi-Agent Systems》2001,4(3):279-282
Autonomous Agents and Multi-Agent Systems - 相似文献
54.
McArthur JM Sikdar PK Nath B Grassineau N Marshall JD Banerjee DM 《Environmental science & technology》2012,46(2):669-676
To reveal what controls the concentration and distribution of possibly hazardous (Mn, U, Se, Cd, Bi, Pb) and nonhazardous (Fe, V, Mo, PO(4)) trace elements in groundwater of the Bengal delta, we mapped their concentrations in shallow groundwater (<60 mbgl) across 102 km(2) of West Bengal. Only Mn is a potential threat to health, with 55% of well water exceeding 0.3 mg/L, the current Indian limit for drinking water in the absence of an alternate source, and 75% exceeding the desirable limit of 0.1 mg/L. Concentrations of V are <3 μg/L. Concentrations of U, Se, Pb, Ni, Bi, and Cd, are below WHO guideline values. The distributions of Fe, Mn, As, V, Mo, U, PO(4), and δ(18)O in groundwater reflect subsurface sedimentology and sources of water. Areas of less negative δ(18)O reveal recharge by sources of evaporated water. Concentrations of Fe, As, Mo, and PO(4) are high in palaeo-channel groundwaters and low in palaeo-interfluvial groundwaters. Concentrations of U, V, and Mn, are low in palaeo-channel groundwaters and high in palaeo-interfluvial groundwaters. Concentrations of Fe and Mn are highest (18 and 6 mg/L respectively) at dual reduction-fronts that form strip interfaces at depth around the edges of palaeo-interfluvial aquifers. The fronts form as focused recharge carries dissolved organic carbon into the aquifer margins, which comprise brown, iron-oxide bearing, sand. At the Mn-reduction front, concentrations of V and Mo reach peak concentrations of 3 μg/L. At the Fe-reduction front, concentrations of PO(4) and As reach concentrations 3 mg/L and 150 μg/L respectively. Many groundwaters contain >10 mg/L of Cl, showing that they are contaminated by Cl of anthropogenic origin and that organic matter from in situ sanitation may contribute to driving reduction. 相似文献
55.
Mammalian herbivores, particularly browsers and folivores, encounter and consume a range of plant chemical defenses [plant secondary metabolites (PSMs)] on a regular basis. The physiological regulation of PSM ingestion and the resulting behavioral responses of mammalian herbivores directly affect their feeding decisions and the subsequent foraging strategies that they adopt. Generalist mammalian herbivores are hypothesized to consume a generalized diet because of physiological limitations of their detoxification systems. The consumption of a generalized diet is proposed to enable toxin (PSM) dilution through the use of multiple detoxification pathways. We tested the predictions of the detoxification–limitation hypothesis by offering two chemically different plant species, Eucalyptus regnans and E. globulus, to a generalist mammalian folivore, the common brushtail possum (Trichosurus vulpecula), as single- and mixed-species diets. By feeding more efficiently, brushtail possums benefited more, through increased intake, on the mixed-species diet than on either of the single-species diets. We argue that frequently switching between chemically diverse foliage reduces the physiological constraints imposed by a PSM-rich diet and enables more efficient feeding. The behavioral responses of brushtail possums were consistent with the proposed physiological constraints of a chemically defended diet, offering support for predictions of the detoxification–limitation hypothesis. We suggest that feeding behavior of herbivores may be a useful indicator of the physiological constraints imposed by a chemically defended diet. 相似文献
56.
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58.
FH Bouwman RL Skolasky D Hes OA Selnes JD Glass TE Nance-Sproson W Royal GJ Dal Pan JC McArthur 《Canadian Metallurgical Quarterly》1998,50(6):1814-1820
A consecutive series of 71 patients diagnosed with HIV-associated dementia (HAD) (1984-1994) were studied to characterize the clinical course of HAD, and to identify predictive markers of rapid neurologic progression. Neurologic progression rate was determined from the change in the Memorial Sloan Kettering (MSK) dementia severity score from diagnosis to death. Those with the most rapid progression in neurologic disability were compared with those with slow or no progression. Autopsy material was immunostained for macrophage activation markers and gp41 in 30 individuals. Median survival was 3.3 months and 6.1 months for rapid-progression and no-progression patients, respectively. Rapid progression was associated with injection drug use but not with race, gender, or age. CD4+ cell counts were lower at diagnosis among rapid-progression than no-progression patients but no differences in AIDS-defining illnesses or patterns of antiretroviral therapy were found. At presentation, rapid-progression patients had more prominent symptoms of mental slowing than those with no progression; however, no other clinical features, CSF, or imaging features distinguished the groups. Less abundant macrophage activation in both basal ganglia and midfrontal gyrus regions, as judged by HAM56 immunostaining, was noted in 9 no-progression patients, compared with 12 rapid-progression patients. Neurologic progression and survival with HAD is highly variable. A significant proportion of individuals with dementia have prolonged survival of more than 12 months and remain cognitively stable. A history of injection drug use and presentation with prominent psychomotor slowing is associated with more rapid neurologic progression, and these patients tend to show more abundant macrophage activation within the CNS. 相似文献
59.
Online diagnostics and online condition monitoring are important functions within the operation and maintenance of power transformers. This paper describes how a multi-agent system (MAS) for transformer condition monitoring has been designed to employ the data generated by the ultra high frequency (UHF) monitoring of partial discharge activity. It describes the rationale behind the use of multi-agent techniques, and the problems overcome through this technology. Every aspect of the MAS design is discussed. In addition, the design and performance of the intelligent interpretation techniques are detailed. 相似文献
60.
P Pevarello A Bonsignori P Dostert F Heidempergher V Pinciroli M Colombo RA McArthur P Salvati C Post RG Fariello M Varasi 《Canadian Metallurgical Quarterly》1998,41(4):579-590
Although most epilepsies are adequately treated by conventional antiepileptic therapy, there remains an unfulfilled need for safer and more effective anticonvulsant agents. Starting from milacemide, a weak anticonvulsant, and trying to elucidate its mechanism of action, we discovered a structurally novel class of potent and preclinically safe anticonvulsants. Here we report the structure-activity relationship (SAR) study within this series of compounds. Different parts of the structural lead 2-[[4-(3-chlorobenzoxy)benzyl]amino]acetamide (6) were thus varied (Figure 1), and many potent anticonvulsants were found. As an outcome of this study, 57 ((S)-2-[[4-(3-fluorobenzoxy)benzyl]amino]propanamide methanesulfonate, PNU-151774E) emerged as a promising candidate for further development for its potent anticonvulsant activity and outstanding therapeutic indexes (TIs) in different animal tests. 相似文献