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101.
Kseniya Khamina Andreas B. Diendorfer Susanna Skalicky Moritz Weigl Marianne Pultar Teresa L. Krammer Catharine Aquino Fournier Amy L. Schofield Carolin Otto Aaron Thomas Smith Nina Buchtele Christian Schoergenhofer Bernd Jilma Bernhard J. H. Frank Jochen G. Hofstaetter Regina Grillari Johannes Grillari Klemens Ruprecht Christopher E. Goldring Hubert Rehrauer Warren E. Glaab Matthias Hackl 《International journal of molecular sciences》2022,23(3)
102.
Payton Beeler Nicholas O. Jensen Soyoung Kim Amy Robichaux-Viehoever Bradley L. Schlaggar Deanna J. Greene Kevin J. Black Rajan K. Chakrabarty 《Journal of the Royal Society Interface》2022,19(187)
Tics manifest as brief, purposeless and unintentional movements or noises that, for many individuals, can be suppressed temporarily with effort. Previous work has hypothesized that the chaotic temporal nature of tics could possess an inherent fractality, that is, have neighbour-to-neighbour correlation at all levels of timescale. However, demonstrating this phenomenon has eluded researchers for more than two decades, primarily because of the challenges associated with estimating the scale-invariant, power law exponent—called the fractal dimension Df—from fractional Brownian noise. Here, we confirm this hypothesis and establish the fractality of tics by examining two tic time series datasets collected 6–12 months apart in children with tics, using random walk models and directional statistics. We find that Df is correlated with tic severity as measured by the YGTTS total tic score, and that Df is a sensitive parameter in examining the effect of several tic suppression conditions on the tic time series. Our findings pave the way for using the fractal nature of tics as a robust quantitative tool for estimating tic severity and treatment effectiveness, as well as a possible marker for differentiating typical from functional tics. 相似文献
103.
Richard A. Veazey Amy S. Gandy Derek C. Sinclair Julian S. Dean 《Journal of the American Ceramic Society》2020,103(4):2702-2714
Micro-contact impedance spectroscopy (MCIS) is potentially a powerful tool for the exploration of resistive surface layers on top of a conductive bulk or substrate material. MCIS employs micro-contacts in contrast to conventional IS where macroscopic electrodes are used. To extract the conductivity of each region accurately using MCIS requires the data to be corrected for geometry. Using finite element modeling on a system where the resistivity of the surface layer is at least a factor of ten greater than the bulk/substrate, we show how current flows through the two layers using two typical micro-contact configurations. This allows us to establish if and what is the most accurate and reliable method for extracting conductivity values for both regions. For a top circular micro-contact and a full bottom counter electrode, the surface layer conductivity (σs) can be accurately extracted using a spreading resistance equation if the thickness is ~10 times the micro-contact radius; however, bulk conductivity (σb) values can not be accurately determined. If the contact radius is 10 times the thickness of the resistive surface, a geometrical factor using the micro-contact area provides accurate σs values. In this case, a spreading resistance equation also provides a good approximation for σb. For two top circular micro-contacts on thin resistive surface layers, the MCIS response from the surface layer is independent of the contact separation; however, the bulk response is dependent on the contact separation and at small separations contact interference occurs. As a consequence, there is not a single ideal experimental setup that works; to obtain accurate σs and σb values the micro-contact radius, surface layer thickness and the contact separation must all be considered together. Here we provide scenarios where accurate σs and σb values can be obtained that highlight the importance of experimental design and where appropriate equations can be employed for thin and thick resistive surface layers. 相似文献
104.
Characterization of products from fast and isothermal hydrothermal liquefaction of microalgae 下载免费PDF全文
Julia L. Faeth Phillip E. Savage Jacqueline M. Jarvis Amy M. McKenna Phillip E. Savage 《American Institute of Chemical Engineers》2016,62(3):815-828
We investigated nonisothermal (fast) and nominally isothermal hydrothermal liquefaction (HTL) of Nannochloropsis sp. microalgae for the production of biocrude. Biocrude yields ranged from 36 to 45 wt % (dry weight), with fast HTL with low mass loading giving the highest yield. This condition also gave the biocrude with the lowest heating value, which indicates there are compromises to be made between biocrude quantity and quality. The aqueous phase and biocrude product fractions were characterized using elemental analysis and Fourier transform ion cyclotron resonance mass spectrometry (FT‐ICR MS). This detailed level of analysis identified more than 30,000 unique molecular products. The aqueous phase products included compounds with the same molecular formulae as known herbicides, which may inform efforts in genetic engineering of algae and/or bacteria for cultivation on the aqueous phase. This detailed molecular‐level characterization provides some clues regarding the types of reactions that may take place during HTL. © 2016 American Institute of Chemical Engineers AIChE J, 62: 815–828, 2016 相似文献
105.
Amy Richards Chakra Wijesundera Phil Salisbury 《Journal of the American Oil Chemists' Society》2008,85(2):159-168
The effects of genotype and growing environment on the tocopherols and fatty acids (FA) of experimental Brassica juncea and B. napus breeding lines were investigated. For both species, with the exception of a few genotypes, the concentration ratio of γ-tocopherols
to α-tocopherol was practically constant. The genotype influenced the tocopherol concentration in B. napus, and to a lesser degree, B. juncea. The environment also had a similar effect, and a positive correlation existed between the daily maximum temperature and
the α-tocopherol concentration in B. napus. Genotype effects on the FA composition were significant for the conventional but not for Clearfield or triazine tolerant
traits of B. napus. The genotype had no effect on the FA of the B. juncea genotypes. In contrast, the growing environment had a significant influence on the FA composition of both species with apparent
influence from temperature and rainfall. For both species, the concentration of γ-tocopherol as well as total tocopherols
was inversely related to the 18:3 concentration, which could have resulted from opposite and independent effects of temperature
on the two variables. No relationship existed between the concentrations of tocopherol and the remaining unsaturated FA 18:1
and 18:2. The positional distribution of unsaturated FA within the oil triacylglycerol was a function of their total concentration. 相似文献
106.
Dr Amy J. C. Trappey C. Richard Liu 《The International Journal of Advanced Manufacturing Technology》1993,8(5):297-304
The geometric and topological specification of a workpiece boundary is usually represented in a specific data format in a CAD database. To retrieve a set of workpiece data, to analyse its shape in addition to the machining requirements, and to determine the proper fixture configuration accordingly, are not trivial tasks when a part has a complicated shape. The real challenge is to recognise and synthesise the shape of a workpiece from its data representation. Consequently, the decision for fixturing can be made when the shape of a workpiece and the relationship of the shape and the fixturing configuration can be derived by a systematic methodology. In this paper, a projective spatial occupancy enumeration (PSOE) approach is applied as a representational and manipulating scheme for developing algorithms in automatic fixture configuration. The workpiece is projected onto the working plane of the fixture baseplate. A 2D projection is defined as a matrix of cells which can represent a workpiece with an arbitrary shape. Using a discrete search based upon the matrix of cells, the fixture types and their locations are generated according to a set of heuristic algorithms. This work is a generalisation and extension of previous works for prismatic parts. The same methodology is equally applicable in general robot grasping. 相似文献
107.
A.W. Moran M. Al-Rammahi C. Zhang D. Bravo S. Calsamiglia S.P. Shirazi-Beechey 《Journal of dairy science》2014
Absorption of glucose from the lumen of the intestine into enterocytes is accomplished by sodium-glucose co-transporter 1 (SGLT1). In the majority of mammalian species, expression (this includes activity) of SGLT1 is upregulated in response to increased dietary monosaccharides. This regulatory pathway is initiated by sensing of luminal sugar by the gut-expressed sweet taste receptor. The objectives of our studies were to determine (1) if the ruminant intestine expresses the sweet taste receptor, which consists of two subunits [taste 1 receptor 2 (T1R2) and 3 (T1R3)], and other key signaling molecules required for SGLT1 upregulation in nonruminant intestines, and (2) whether T1R2-T1R3 sensing of artificial sweeteners induces release of glucagon-like peptide-2 (GLP-2) and enhances SGLT1 expression. We found that the small intestine of sheep and cattle express T1R2, T1R3, G-protein gustducin, and GLP-2 in enteroendocrine L-cells. Maintaining 110-d-old ruminating calves for 60 d on a diet containing a starter concentrate and the artificial sweetener Sucram (consisting of saccharin and neohesperidin dihydrochalcone; Pancosma SA, Geneva, Switzerland) enhances (1) Na+-dependent d-glucose uptake by over 3-fold, (2) villus height and crypt depth by 1.4- and 1.2-fold, and (3) maltase- and alkaline phosphatase-specific activity by 1.5-fold compared to calves maintained on the same diet without Sucram. No statistically significant differences were observed for rates of intestinal glucose uptake, villus height, crypt depth, or enzyme activities between 50-d-old milk-fed calves and calves maintained on the same diet containing Sucram. When adult cows were kept on a diet containing 80:20 ryegrass hay-to-concentrate supplemented with Sucram, more than a 7-fold increase in SGLT1 protein abundance was noted. Collectively, the data indicate that inclusion of this artificial sweetener enhances SGLT1 expression and mucosal growth in ruminant animals. Exposure of ruminant sheep intestinal segments to saccharin or neohesperidin dihydrochalcone evokes secretion of GLP-2, the gut hormone known to enhance intestinal glucose absorption and mucosal growth. Artificial sweeteners, such as Sucram, at small concentrations are potent activators of T1R2-T1R3 (600-fold > glucose). This, combined with oral bioavailability of T1R2-T1R3 and the understanding that artificial sweetener-induced receptor activation evokes GLP-2 release (thus leading to increased SGLT1 expression and mucosal growth), make this receptor a suitable target for dietary manipulation. 相似文献
108.
Wilhelmina Kalt Shawna MacKinnon Jane McDonald Melinda Vinqvist Cheryl Craft Amy Howell 《Journal of the science of food and agriculture》2008,88(1):68-76
The concentrations and profiles of phenolics of selected fruit crops common in the Western diet, including several Vaccinium species, were examined to better understand how these crops may be useful sources of phenolic phytochemicals. Vaccinium fruit had a high phenolic concentration compared to non‐Vaccinium fruit. Some Vaccinium fruit were particularly rich in certain phenolic subgroups, especially anthocyanins and pro‐anthocyanidins. Among the pro‐anthocyanidin oligomers measured using fluorometric and mass spectroscopic detection, the trimers and tetramers were most abundant, while pro‐anthocyanidins with a degree of polymerization greater than 8 were least abundant. As biomedical studies determine which phenolic structures are associated with particular bioactivities, information on the phenolic concentration and profile of selected species will be useful in developing specific uses for fruit crops in human health. Methods were compared to assess the usefulness of simpler versus more sophisticated means of phenolic analysis. The phenolic components of fruit extracts were purified approximately 20‐fold, and not qualitatively altered, by C18 solid‐phase extraction. However, fruit extracts obtained from C18 solid‐phase extraction differed in their relative abundance of phenolic components. Colorimetric and HPLC‐DAD measures of phenolic concentration were correlated (R2 = 0.79), as was pro‐anthocyanidin concentration detected fluorometrically and by mass spectrometry (R2 = 0.44). Copyright © 2007 Crown in the right of Canada and Society of Chemical Industry 相似文献
109.
We propose a novel algorithm for counting N indistinguishable objects, called targets, by a collection of sensors. We adopt a minimalist scenario where sensors are unaware of the (non-empty) intersections of sensing regions, and so simple addition of all sensor counts inflates estimates of the total number of targets. The multiple counting in intersections must be accounted for, but with nothing more than the sensor counts, this is clearly impossible. However, noise is typically present in the target counting of many, if not most, applications. We make the key observation that if there is a (target-dependent) noise source affecting all sensors simultaneously, then it couples those with non-empty intersections. Exploitation of this coupling allows us to extract multiple-counting statistics from stochastic correlation patterns, and hence to compute accurate estimates of N via the classical inclusion–exclusion formula. Cumulants are the correlation measures of choice. Our analysis brings out and resolves certain technicalities that arise in our statistical counting algorithm. Examples are worked out to show the potential of the new algorithm. The paper concludes with a discussion of alternative models and open problems. 相似文献
110.