166 research outputs found
Trace elements in home-processed food obtained from unconventional animals
Wild animals have been used as food since ancient times and, currently, the consumption of unconventional animals is increasing worldwide. The process of cooking meat using traditional recipes includes a variety of ingredients, which can influence the total metal intake from the diet. In this study, the concentrations of eight essential (Fe, Zn, Cu, Mn, Se, Ni, Mo, and Co) and six non-essential (Pb, Cd, Hg, Al, As, and Cr) trace elements were determined in home-processed food obtained from snails and from three common species of game animals (woodcock, pheasant, and hare), seasoned with anchovies, mushrooms, and different vegetables using inductively coupled plasma mass spectrometry (ICP-MS). In general, Fe was the most abundant trace element, ranging from 18 \ub1 8 \u3bcg/g in pheasant to 99 \ub1 76 \u3bcg/g in snail, and Co was the least abundant, ranging from 0.007 \ub1 0.003 \u3bcg/g in hare to 0.093 \ub1 0.048 \u3bcg/g in snail. Regarding the non-essential trace elements, Pb concentrations showed wide variations, reaching a concentration of 17.30 \u3bcg/g in hare, while Cd concentrations were higher in snail, ranging from 0.18 to 0.46 \u3bcg/g. These alternative food sources can offer an important contribution to the human nutritional requirements of essential trace elements, in particular of Fe. The high concentrations of Pb and Cd present in some samples should be considered as potentially dangerous for the consumers
Coherent ultrafast spin-dynamics probed in three dimensional topological insulators
Topological insulators are candidates to open up a novel route in spin based
electronics. Different to traditional ferromagnetic materials, where the
carrier spin-polarization and magnetization are based on the exchange
interaction, the spin properties in topological insulators are based on the
coupling of spin- and orbit interaction connected to its momentum. Specific
ways to control the spin-polarization with light have been demonstrated: the
energy momentum landscape of the Dirac cone provides spin-momentum locking of
the charge current and its spin. The directionality of spin and momentum, as
well as control with light has been demonstrated. Here we demonstrate a
coherent femtosecond control of spin-polarization for states in the valence
band at around the Dirac cone.Comment: 14 pages, 4 figure
Magnetic anisotropy at the buried CoO/Fe interface
Interfaces between antiferromagnetic CoO and ferromagnetic Fe are typically characterized by the development of Fe oxides. Recently, it was shown that the use of a proper ultra-thin Co buffer layer prevents the formation of Fe oxides [Brambilla et al., Appl. Surf. Sci. 362, 374 (2016)]. In the present work, we investigate the magnetic properties of such an interface, and we find evidence for an in-plane uniaxial magnetic anisotropy, which is characterized by a multijump reversal behavior in the magnetization hysteresis loops. X-ray photoemission spectroscopy and element-sensitive hysteresis loops reveal that the occurrence of such an anisotropy is a phenomenon developing at the very interface
Coherent phonons and the interplay between charge density wave and Mott phases in 1-TaSe
1-TaSe is host to coexisting strongly-correlated phases including
charge density waves (CDWs) and an unusual Mott transition at low temperature.
Here, we investigate coherent phonon oscillations in 1-TaSe using a
combination of time- and angle-resolved photoemission spectroscopy (TR-ARPES)
and time-resolved reflectivity (TRR). Perturbation by a femtosecond laser pulse
triggers a modulation of the valence band binding energy at the -point,
related to the Mott gap, that is consistent with the in-plane CDW amplitude
mode frequency. By contrast, TRR measurements show a modulation of the
differential reflectivity comprised of multiple frequencies belonging to the
distorted CDW lattice modes. Comparison of the temperature dependence of
coherent and spontaneous phonons across the CDW transition shows that the
amplitude mode intensity is more easily suppressed during perturbation of the
CDW state by the optical excitation compared to other modes. Our results
clearly identify the relationship of the in-plane CDW amplitude mode with the
Mott phase in 1-TaSe and highlight the importance of lattice degrees
of freedom.Comment: 7 pages, 4 figures, supplemental materia
Implication for Functions of the Ectopic Adipocyte Copper Amine Oxidase (AOC3) from Purified Enzyme and Cell-Based Kinetic Studies
AOC3 is highly expressed in adipocytes and smooth muscle cells, but its function in these cells is currently unknown. The in vivo substrate(s) of AOC3 is/are also unknown, but could provide an invaluable clue to the enzyme's function. Expression of untagged, soluble human AOC3 in insect cells provides a relatively simple means of obtaining pure enzyme. Characterization of enzyme indicates a 6% titer for the active site 2,4,5-trihydroxyphenylalanine quinone (TPQ) cofactor and corrected kcat values as high as 7 sâ1. Substrate kinetic profiling shows that the enzyme accepts a variety of primary amines with different chemical features, including nonphysiological branched-chain and aliphatic amines, with measured kcat/Km values between 102 and 104 Mâ1 sâ1. Km(O2) approximates the partial pressure of oxygen found in the interstitial space. Comparison of the properties of purified murine to human enzyme indicates kcat/Km values that are within 3 to 4-fold, with the exception of methylamine and aminoacetone that are ca. 10-fold more active with human AOC3. With drug development efforts investigating AOC3 as an anti-inflammatory target, these studies suggest that caution is called for when screening the efficacy of inhibitors designed against human enzymes in non-transgenic mouse models. Differentiated murine 3T3-L1 adipocytes show a uniform distribution of AOC3 on the cell surface and whole cell Km values that are reasonably close to values measured using purified enzymes. The latter studies support a relevance of the kinetic parameters measured with isolated AOC3 variants to adipocyte function. From our studies, a number of possible substrates with relatively high kcat/Km have been discovered, including dopamine and cysteamine, which may implicate a role for adipocyte AOC3 in insulin-signaling and fatty acid metabolism, respectively. Finally, the demonstrated AOC3 turnover of primary amines that are non-native to human tissue suggests possible roles for the adipocyte enzyme in subcutaneous bacterial infiltration and obesity
Recent progress in photonic processing of metalâoxide transistors
Over the past few decades, significant progress has been made in the field of photonic processing of electronic materials using a variety of light sources. Several of these technologies have now been exploited in conjunction with emerging electronic materials as alternatives to conventional high temperature thermal annealing offering rapid manufacturing times and compatibility with temperature-sensitive substrate materials among other potential advantages. A review of recent advances in photonic processing paradigms of metal oxide thin film transistors (TFTs), is presented with particular emphasis on the use of various light source technologies for the photochemical and thermochemical conversion of precursor materials or post-deposition treatment of metal oxides and their application in thin-film electronics. The pros and cons of the different technologies are discussed in light of recent developments and prospective research in the field of modern large-area electronics is highlighted
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