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101.
Sara Azevedo Ana M. S. Costa Amanda Andersen Insung S. Choi Henrik Birkedal João F. Mano 《Advanced materials (Deerfield Beach, Fla.)》2017,29(28)
Inspired by the mussel byssus adhesiveness, a highly hydrated polymeric structure is designed to combine, for the first time, a set of interesting features for load‐bearing purposes. These characteristics include: i) a compressive strength and stiffness in the MPa range, ii) toughness and the ability to recover it upon successive cyclic loading, iii) the ability to quickly self‐heal upon rupture, iv) the possibility of administration through minimally invasive techniques, such as by injection, v) the swelling ratio being adjusted to space‐filling applications, and vi) cytocompatibility. Owing to these characteristics and the mild conditions employed, the encapsulation of very unstable and sensitive cargoes is possible, highlighting their potential to researchers in the biomedical field for the repair of load‐bearing soft tissues, or to be used as an encapsulation platform for a variety of biological applications such as disease models for drug screening and therapies in a more realistic mechanical environment. Moreover, given the simplicity of this methodology and the enhanced mechanical performance, this strategy can be expanded to applications in other fields, such as agriculture and electronics. As such, it is anticipated that the proposed strategy will constitute a new, versatile, and cost‐effective tool to produce engineered polymeric structures for both science and technology. 相似文献
102.
A comprehensive experimental investigation relevant to thermal radiation has been performed in a grate-fired test furnace. Thermal radiation is the dominating mode of heat transfer in the grate-fired furnace and yet only a few studies have focused on thermal radiation. No previous works, to the authors' knowledge, have been carried out concerning measurements on radiative heat transfer in grate-fired furnaces. In this work measurements of temperature have been carried out for all boundaries and the flue gases at a large number of locations. The gas species volume fraction, particle mass–size distributions, and wall irradiation have also been measured at a number of spatial locations. These data are useful in a computational framework to describe the radiative heat transfer reaching the boundaries. Comparing modeled wall irradiation to the measured one makes it possible to obtain a deeper insight into the thermal radiative transport inside the grate-fired furnace. 相似文献
103.
Gradient meshes are a 2D vector graphics primitive where colour is interpolated between mesh vertices. The current implementations of gradient meshes are restricted to rectangular mesh topology. Our new interpolation method relaxes this restriction by supporting arbitrary manifold topology of the input gradient mesh. Our method is based on the Catmull‐Clark subdivision scheme, which is well‐known to support arbitrary mesh topology in 3D. We adapt this scheme to support gradient mesh colour interpolation, adding extensions to handle interpolation of colours of the control points, interpolation only inside the given colour space and emulation of gradient constraints seen in related closed‐form solutions. These extensions make subdivision a viable option for interpolating arbitrary‐topology gradient meshes for 2D vector graphics. 相似文献
104.
Simon Sjödin Oskar Hansson Annika Öhrfelt Gunnar Brinkmalm Henrik Zetterberg Ann Brinkmalm Kaj Blennow 《Proteomics. Clinical applications》2017,11(11-12)
1 Purpose
Dysfunctional proteostasis, with decreased protein degradation and an accumulation of ubiquitin into aggregated protein inclusions, is a feature of neurodegenerative diseases. Identifying new potential biomarkers in cerebrospinal fluid (CSF) reflecting this process could contribute important information on pathophysiology.2 Experimental design
A developed method combining SPE and PRM‐MS is employed to monitor the concentration of ubiquitin in CSF from subjects with Alzheimer's disease (AD), Parkinson's disease (PD), and progressive supranuclear palsy (PSP). Four independent cross‐sectional studies are conducted, studies 1–4, including controls (n = 86) and participants with AD (n = 60), PD (n = 15), and PSP (n = 11).3 Results
The method shows a repeatability and intermediate precision not exceeding 6.1 and 7.9%, respectively. The determined LOD is 0.1 nm and the LOQ range between 0.625 and 80 nm . The CSF ubiquitin concentration is 1.2–1.5‐fold higher in AD patients compared with controls in the three independent AD‐control studies (Study 1, p < 0.001; Study 2, p < 0.001; and Study 3, p = 0.003). In the fourth study, there is no difference in PD or PSP, compared to controls.4 Conclusion and clinical relevance
CSF ubiquitin may reflect dysfunctional proteostasis in AD. The described method can be used for further exploration of ubiquitin as a potential biomarker in neurodegenerative diseases. 相似文献105.
Amelie S. Wilde Anne-Mette S. Hansen Arvid Fromberg Henrik Lauritz Frandsen Jørn Smedsgaard 《Flavour and Fragrance Journal》2020,35(4):387-393
Vanilla is one of the most popular spices in the world and is therefore often added to food products to enhance the taste with its desirable flavour. Vanilla flavour is highly susceptible to economically motivated food fraud since the main component ‘vanillin’ can easily be produced by much cheaper synthetic processes. The determination of the vanillin source is not always an easy task, especially when very low concentrations are incorporated in complex food matrices. Here, we present an easy sample preparation procedure that includes a solid-phase extraction clean-up to determine the isotopic carbon ratio of vanillin in food products by headspace solid-phase microextraction and gas chromatography coupled to isotope ratio mass spectrometry. Isotopic fractionation during the sample preparation procedure was carefully evaluated. The method was applied to 23 commercial food samples including vanilla sugar, dairy and soy products. The study illustrates the potential and limitations of the authentication of vanilla flavour by the isotopic carbon ratio of vanillin. Further, the complexity of the authenticity assessment of vanilla flavours in composite food is demonstrated. 相似文献
106.
Henrik Beelen Kartik Mundaragi Shivakumar Luc Raijmakers M.C.F. Donkers Henk Jan Bergveld 《国际能源研究杂志》2020,44(4):2889-2908
In order to meet the required power and energy demand of battery-powered applications, battery packs are constructed from a multitude of battery cells. For safety and control purposes, an accurate estimate of the temperature of each battery cell is of vital importance. Using electrochemical impedance spectroscopy (EIS), the battery temperature can be inferred from the impedance. However, performing EIS measurements simultaneously at the same frequency on each cell in a battery pack introduces crosstalk interference in surrounding cells, which may cause EIS measurements in battery packs to be inaccurate. Also, currents flowing through the pack interfere with impedance measurements on the cell level. In this paper, we propose, analyse, and validate a method for estimating the battery temperature in a battery pack in the presence of these disturbances. First, we extend an existing and effective estimation framework for impedance-based temperature estimation towards estimating the temperature of each cell in a pack in the presence of crosstalk and (dis)charge currents. Second, the proposed method is analysed and validated on a two-cell battery pack, which is the first step towards development of this method for a full-size battery pack. Monte Carlo simulations are used to find suitable measurement settings that yield small estimation errors and it is demonstrated experimentally that, over a range of temperatures, the method yields an accuracy of ±1°C in terms of bias, in the presence of both disturbances. 相似文献
107.
108.
109.
Murvoll KM Skaare JU Jensen H Jenssen BM 《The Science of the total environment》2007,381(1-3):134-145
The aim of the study was to examine associations between persistent organic pollutants and vitamin A (retinol), retinyl palmitate and vitamin E status (alpha-tocopherol) in two species occupying different trophic positions in the Arctic food web. Levels of polychlorinated biphenyls (PCBs), some selected organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD) were analyzed in yolk sac of newly hatched chicks of Brünnich's guillemot (Uria lomvia) and common eider (Somateria mollissima) from Kongsfjorden, Svalbard (Norwegian Arctic) (79 degrees N). Morphological variables were measured, and levels of retinol, retinyl palmitate and alpha-tocopherol were analyzed in plasma and liver. Brünnich's guillemot had significantly higher levels of POPs than common eider, as expected from its higher trophic position. Morphological traits seemed to be negatively related to POPs in Brünnich's guillemots, but not in common eiders. In Brünnich's guillemot, negative relationships were found between some OCPs (hexachlorobenzene, oxychlordane, p,p'-DDE) and liver alpha-tocopherol levels. The negative relationships between these OCPs and liver alpha-tocopherol levels in Brünnich's guillemot hatchlings became less evident when the confounding effect of liver mass was corrected for. In common eider positive relationships were found between summed PCB (SigmaPCBs) and some OCPs (beta-hexachlorocyclohexane, oxychlordane) and liver alpha-tocopherol levels. Differences in relationships between POPs and vitamin status in the two species may be related to differences in POP exposure levels linked to their trophic position in the Arctic marine food web, or to intrinsic physiological differences between the species. 相似文献
110.
Henrik Bjelland Ove Njå Atle William Heskestad Geir Sverre Braut 《Fire Technology》2015,51(2):409-441