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排序方式: 共有2234条查询结果,搜索用时 11 毫秒
951.
952.
Irene Schilcher Julia T. Stadler Margarete Lechleitner Andelko Hrzenjak Andrea Berghold Gudrun Pregartner Marie Lhomme Michael Holzer Melanie Korbelius Florian Reichmann Anna Springer Christian Wadsack Tobias Madl Dagmar Kratky Anatol Kontush Gunther Marsche Saa Frank 《International journal of molecular sciences》2021,22(2)
Endothelial lipase (EL) is a strong modulator of the high-density lipoprotein (HDL) structure, composition, and function. Here, we examined the impact of EL on HDL paraoxonase 1 (PON1) content and arylesterase (AE) activity in vitro and in vivo. The incubation of HDL with EL-overexpressing HepG2 cells decreased HDL size, PON1 content, and AE activity. The EL modification of HDL did not diminish the capacity of HDL to associate with PON1 when EL-modified HDL was incubated with PON1-overexpressing cells. The overexpression of EL in mice significantly decreased HDL serum levels but unexpectedly increased HDL PON1 content and HDL AE activity. Enzymatically inactive EL had no effect on the PON1 content of HDL in mice. In healthy subjects, EL serum levels were not significantly correlated with HDL levels. However, HDL PON1 content was positively associated with EL serum levels. The EL-induced changes in the HDL-lipid composition were not linked to the HDL PON1 content. We conclude that primarily, the interaction of enzymatically active EL with HDL, rather than EL-induced alterations in HDL size and composition, causes PON1 displacement from HDL in vitro. In vivo, the EL-mediated reduction of HDL serum levels and the consequently increased PON1-to-HDL ratio in serum increase HDL PON1 content and AE activity in mice. In humans, additional mechanisms appear to underlie the association of EL serum levels and HDL PON1 content. 相似文献
953.
Swagato Sarkar Vaibhav Gupta Takuya Tsuda Jeetendra Gour Arvind Singh Olha Aftenieva Anja M. Steiner Marisa Hoffmann Sunil Kumar Andreas Fery Joby Joseph Tobias A.F. König 《Advanced functional materials》2021,31(19):2011099
The challenges in plasmonic charge transfer on a large-scale and low losses are systematically investigated by optical designs using 1D-plasmonic lattice structures. These plasmonic lattices are used as couplers to guide the energy in an underneath sub-wavelength titanium dioxide layer, resulting in the photonic crystal slabs. So far, photodetection is possible at energy levels close to the semiconductor bandgap; however, with the observed hybrid plasmonic–photonic modes, other wavelengths over the broad solar spectrum can be easily accessed for energy harvesting. The photo-enhanced current is measured locally with simple two-point contact on the centimeter-squared nanostructure by applying a bias voltage. As lattice couplers, interference lithographically fabricated conventional gold grating provides an advantage in fabrication; this optical concept is extended for the first time toward colloidal self-assembled nanoparticle chains to make the charge injection accessible for large-scale at reasonable costs with possibilities of photodetection by electric field vectors both along and perpendicular to the grating lines. To discuss the bottleneck of unavoidable isolating ligand shell of nanoparticles in contrast to the directly contacted nanobars, polarization-dependent ultrafast characterizations are carried out to study the charge injection processes in femtosecond resolution. 相似文献
954.
Flexible Magnetoreceptor with Tunable Intrinsic Logic for On-Skin Touchless Human-Machine Interfaces
Pavlo Makushko Eduardo Sergio Oliveros Mata Gilbert Santiago Cañón Bermúdez Mariam Hassan Sara Laureti Christian Rinaldi Federico Fagiani Gianni Barucca Nataliia Schmidt Yevhen Zabila Tobias Kosub Rico Illing Oleksii Volkov Igor Vladymyrskyi Jürgen Fassbender Manfred Albrecht Gaspare Varvaro Denys Makarov 《Advanced functional materials》2021,31(25):2101089
Artificial magnetoception is a new and yet to be explored path for humans to interact with the surroundings. This technology is enabled by thin film magnetic field sensors embedded in a soft and flexible format to constitute magnetosensitive electronic skins (e-skins). Being limited by the sensitivity to in-plane magnetic fields, magnetosensitive e-skins are restricted to basic proximity and angle sensing and are not used as switches or logic elements of interactive wearable electronics. Here, a novel magnetoreceptive platform for on-skin touchless interactive electronics based on flexible spin valve switches with sensitivity to out-of-plane magnetic fields is demonstrated. The technology relies on all-metal Co/Pd-based spin valves with a synthetic antiferromagnet possessing perpendicular magnetic anisotropy. The flexible magnetoreceptors act as logic elements, namely momentary and permanent (latching) switches. The switches maintain their performance even upon bending to a radius of less than 3.5 mm and withstand repetitive bending for hundreds of cycles. Here, flexible switches are integrated in on-skin interactive electronics and their performance as touchless human-machine interfaces is demonstrated, which are intuitive to use, energy efficient, and insensitive to external magnetic disturbances. This technology offers qualitatively new functionalities for electronic skins and paves the way towards full-fledged on-skin touchless interactive electronics. 相似文献
955.
E. Celeste Welch Jessica M. Powell Tobias B. Clevinger Alexis E. Fairman Anita Shukla 《Advanced functional materials》2021,31(44):2104126
Nanoscale materials have unique properties that make them especially useful for biomedical diagnostic applications. Recent developments in nanoengineering have resulted in increasing use of nanostructures in biosensors. Various types of 0D, 1D, 2D, and 3D nanostructures have been used to improve biosensor sensitivity, selectivity, limit of detection, and time to result, among other metrics. These nanostructures have been integrated into electrochemical, optical, and other biosensors for this purpose. Here, the most recent advances in the use of nanostructured materials in biosensors are described. This includes a discussion of nanoparticles, nanorods, nanofibers, nanopillars, nanowires, nanosheets, indented nanopatterns (nanoholes and nanoslits), nanogaps, nanochannels, nanopores, nanofunctionalized surfaces, and complex hierarchical structures and their unique advantages and applications in biosensors. Clinical applications of these nanobiosensors are also highlighted along with a discussion of the future directions for these materials in diagnostics. 相似文献
956.
Danny Westphal Tobias Teumer Thomas Schäfer Rolf-Jürgen Ahlers Matthias Rädle 《化学,工程师,技术》2021,93(10):1636-1642
Aerosols contain liquid and/or solid particles, which can pose a significant risk to humans. In order to detect these potential hazards at an early stage, this paper shows the possibility of measuring aerosols with an adapted particle sensor system (ProxiCube®) and displaying the liquid and solid components separately. To demonstrate the reproducibility of the measurements, samples are monitored simultaneously with two ProxiCubes and a well-established reference system. 相似文献
957.
Tobias Weissenberger Albert G. F. Machoke Joel M. Kolle Yamini S. Avadhut Martin Hartmann Wilhelm Schwieger 《化学,工程师,技术》2021,93(6):1001-1010
A one-pot synthesis of aluminium-containing mesoporous silica particles (Al-MSPs) utilizing polyvinyl alcohol (PVA) as steric stabilization agent is reported. PVA prevents particle agglomeration even when the ionic aluminium source is present in the synthesis mixture. Silicon and aluminium sources were utilised completely, resulting in high yield and easy adjustment of the Si/Al ratio. The Al-MSPs showed a spherical morphology, high surface area and were active for the liquid-phase Beckmann rearrangement of cyclohexanone to caprolactam. 相似文献
958.
Sara Pacheco-Pappenheim Sine Yener Jeroen M.L. Heck Jan Dijkstra Hein J.F. van Valenberg 《Journal of dairy science》2021,104(8):8479-8492
The aim of this study was to assess the effects of seasonal variation on the changes of the fatty acid (FA) and triacylglycerol (TAG) composition of bovine milk fat (MF) in a nonseasonal milking system. Weekly milk samples were collected from 14 dairy factories and pooled per week as representative samples of the average Dutch bovine milk. The sample collection started in May 2017 and finished in April 2018, resulting in a total of 52 samples, corresponding to each week of the year. The samples were analyzed for MF content (%) and FA and TAG composition using gas chromatography with flame-ionization detection. The increased intake of C18:3 cis-9,12,15 through grass feeding in spring and summer was associated with major changes in MF FA composition, including reduced proportions of de novo synthesized FA and presence of several rumen biohydrogenation products and conjugated linoleic acid isomers in MF. These changes in seasonal FA composition had an effect on TAG seasonal variation. The TAG seasonal variation showed that all TAG groups were significantly different between months. The low molecular weight and the medium molecular weight TAG groups increased in winter and decreased in summer, whereas the high molecular weight TAG groups increased in summer and decreased in winter. Based on pooled monthly samples, MALDI-TOF-mass spectrometry allowed the analysis of even- and odd-chain TAG species in MF based on their total carbon number and number of double bonds. These analyses indicated saturated TAG species to be greatest in winter, whereas monounsaturated, polyunsaturated, and odd-chain TAG species were greatest in summer. Our study showed that TAG seasonal variation in a nonseasonal milking system is influenced by the variation in FA composition throughout the seasons. 相似文献
959.
Julius Juma Okello Felix Mwala Shiundu Janet Mwende Carl Johan Lagerkvist Rose Adhiambo Nyikal Penina Muoki John Mburu Jan Low Guy Hareau Simon Heck 《International Journal of Food Science & Technology》2021,56(3):1432-1446
This 2018 study, conducted in six Tusky's supermarkets in Nairobi, Kenya, combined the Just-About-Right, Penalty and Mean-End-Chain analyses to examine the quality and psychosocial factors influencing the purchase of a novel bread made from orange-fleshed sweet potato (OFSP), a biofortified crop, focusing on sixty-one male and eighty female urban OFSP bread buyers recruited at point of purchase. It finds that sensory and psychosocial factors drive purchasing decisions and that some of the bread's sensory characteristics are misaligned with consumers' expectations. It also finds that women and men’s evaluations of the bread's characteristics are different, as are their motivations for purchase. However, good sensory attributes and the knowledge of the bread's nutritional value were key drivers. Some misaligned characteristics reveal levers for the reformulation of the bread and present opportunities for segmenting the market. Several other implications of the findings for policy and future improvement of the bread are discussed. 相似文献
960.
Pieter Nachtergaele Tobias de Somer Bastiaan Gelaude Joël Hogie Joris W. Thybaut Steven de Meester David Drijvers Jo Dewulf 《American Institute of Chemical Engineers》2021,67(6):e17235
The complexity of lipid feedstocks and the lack of data on physical properties hinder the simulation of oleochemical processing units. In this work, an iterative lumping approach is proposed to define an adequate number of key compounds such that diversification between lipid feedstocks becomes possible, while keeping the determination of physical properties as required for process modeling manageable. As a case study, the iterative lumping approach is used for simulation and optimization of a fatty acid distillation plant. For predicting vapor–liquid equilibria of fatty acids, the best results were acquired using the property method universal quasichemical-Hayden–O'Conell. Using the iterative lumping approach, 11 key compounds were selected to represent the feedstock. The process model properly predicts the product composition, yield, purity and heat duty. The most important process parameters are found to be side-reflux-ratio, reboiler-outlet-temperature, and heat-duty of the pitch-distiller. For optimization, an increase of the side-reflux-ratio and reboiler-outlet-temperature is recommended. 相似文献