Wave Function Engineering on Superconducting Substrates: Chiral Yu-Shiba-Rusinov Molecules.

Magnetic adatoms on superconductors give rise to Yu-Shiba-Rusinov (YSR) states that hold considerable interest for the design of topological superconductivity. Here, we show that YSR states are also an ideal platform to engineer structures with intricate wave function symmetries. We assemble structures of iron atoms on the quasi-two-dimensional superconductor 2-NbSe.

Robust Spectral π Pairing in the Random-Field Floquet Quantum Ising Model.

Motivated by an experiment on a superconducting quantum processor [X. Mi et al., Science 378, 785 (2022).

Energy-use efficiency of organic and conventional plant production systems in Germany.

Sustainable and efficient energy use in agriculture helps tackle climate change by reducing fossil energy use. We evaluated German farming systems by analysing energy input and output. Data from 30 organic and 30 conventional farms (12 arable, 18 dairy farms each) between 2009 and 2011 was used.

Quantization of Integrable and Chaotic Three-Particle Fermi-Pasta-Ulam-Tsingou Models.

We study the transition from integrability to chaos for the three-particle Fermi-Pasta-Ulam-Tsingou (FPUT) model. We can show that both the quartic β-FPUT model (α=0) and the cubic one (β=0) are integrable by introducing an appropriate Fourier representation to express the nonlinear terms of the Hamiltonian. For generic values of α and β, the model is non-integrable and displays a mixed phase space with both chaotic and regular trajectories.

Tricritical point in the quantum Hamiltonian mean-field model.

Engineering long-range interactions in experimental platforms has been achieved with great success in a large variety of quantum systems in recent years. Inspired by this progress, we propose a generalization of the classical Hamiltonian mean-field model to fermionic particles. We study the phase diagram and thermodynamic properties of the model in the canonical ensemble for ferromagnetic interactions as a function of temperature and hopping.

Discovering a New Metabolic Pathway. Early Work with My Friend, Viswanathan Natarajan.

This article summarizes our early work with Viswanathan Natarajan in the 1980s at the University of Minnesota's Hormel Institute, when he was at the beginning of his brilliant academic career. At that time most metabolic pathways for the biosynthesis and degradation of phospholipids were well established and known in considerable detail. Hence, it was exciting to discover a novel sequence of biochemical reactions, first in dog heart and later in various other vertebrate cells and tissues that became known as the transacylation-phosphodiesterase pathway of phospholipid metabolism.

An approximate solution of the interferon-dependent viral kinetics model of influenza.

The analysis of viral kinetics models is mostly achieved by numerical methods. We present an approach via a Magnus expansion that allows us to give an approximate solution to the interferon-dependent viral infection model of influenza which is compared with numerical results. The time of peak viral load is calculated from the approximation and stays within 10% in the studied range of interferon (IFN) efficacy ϵ ∈ [0, 1000].

A Framework to Evaluate the Impact of Armourstones on the Chemical Quality of Surface Water.

Today, basic requirements for construction works include the protection of human health and of the environment. In the tension area between economic demands, circular flow economy and environmental safety, a link between the results from standardized leaching tests and the respective environmental quality standards must be created. To derive maximum release limits of metals and metalloids for armourstones in hydraulic engineering, this link is accomplished via a simple model approach.

Lipoxygenase-catalyzed phospholipid peroxidation: preparation, purification, and characterization of phosphatidylinositol peroxides.

The importance of understanding the mechanisms of modulation of cellular signaling cascades by the peroxidized membrane phospholipids (PLs) is well recognized. The enzyme-catalyzed peroxidation of PLs, as opposed to their oxidation by air and metal catalysis, is well controlled and rapid and yields well-defined PL peroxides which are highly desirable for biological studies. Therefore, here, we chose bovine liver phosphatidylinositol (PI), a crucial membrane PL which acts as the substrate for phospholipase C in cellular signal transduction, as a model membrane PL.

Intestinal levels of anandamide and oleoylethanolamide in food-deprived rats are regulated through their precursors.

The anorectic lipid oleoylethanolamide and the orexigenic lipid anandamide both belong to the group of N-acylethanolamines that are generated by the enzyme N-acylphosphatidylethanolamine-hydrolyzing phospholipase D. The levels of the two bioactive lipids were investigated in rat intestines after 24 h of starvation as well as after 1 and 4 h of re-feeding. Total levels of precursor phospholipids and N-acylethanolamines were decreased upon food-deprivation whereas the level of the anandamide precursor molecule was significantly increased.

N-acylphosphatidylethanolamine-hydrolyzing phospholipase D is an important determinant of uterine anandamide levels during implantation.

Implantation requires reciprocal interaction between blastocysts and a receptive uterus. In mice, one important player in this dialogue involves endocannabinoid signaling via cannabinoid receptor CB1. Anandamide is an endogenous cannabinoid ligand, and its levels are spatiotemporally regulated in the uterus during early pregnancy, showing lower levels in the receptive uterus and at the implantation site.

Presence and potential signaling function of N-acylethanolamines and their phospholipid precursors in the yeast Saccharomyces cerevisiae.

N-acylethanolamines (NAEs) and N-acylphosphatidylethanolamines (NAPEs) are trace constituents of vertebrate cells and tissues and much is known about their metabolism and possible function in animals. Here we report for the first time the identification and quantification of NAEs and NAPEs in several strains of the yeast Saccharomyces cerevisiae. Gas chromatography-mass spectrometry of appropriate derivatives revealed 16:0, 16:1, 18:0 and 18:1 N-acyl groups in both NAE and NAPE whose levels, in wild-type cells, were 50 to 90 and 85 to 750 pmol/micromol lipid P, respectively (depending on the phase of growth).

Endocannabinoid metabolism in human glioblastomas and meningiomas compared to human non-tumour brain tissue.

The endogenous levels of the two cannabinoid receptor ligands 2-arachidonoyl glycerol and anandamide, and their respective congeners, monoacyl glycerols and N-acylethanolamines, as well as the phospholipid precursors of N-acylethanolamines, were measured by gas chromatography-mass spectrometry in glioblastoma (WHO grade IV) tissue and meningioma (WHO grade I) tissue and compared with human non-tumour brain tissue. Furthermore, the metabolic turnover of N-acylethanolamines was compared by measurements of the enzymatic activity of N-acyltransferase, N-acylphosphatidylethanolamine-hydrolysing phospholipase D and fatty acid amide hydrolase in the same three types of tissue. Glioblastomas were characterized by enhanced levels of N-acylethanolamines (eightfold, 128 +/- 59 pmol/micromol lipid phosphorus) including anandamide (17-fold, 4.

Mammalian cells stably overexpressing N-acylphosphatidylethanolamine-hydrolysing phospholipase D exhibit significantly decreased levels of N-acylphosphatidylethanolamines.

In animal tissues, NAEs (N-acylethanolamines), including N-arachidonoylethanolamine (anandamide), are primarily formed from their corresponding NAPEs (N-acylphosphatidylethanolamines) by a phosphodiesterase of the PLD (phospholipase D) type (NAPE-PLD). Recently, we cloned cDNAs of NAPE-PLD from mouse, rat and human [Okamoto, Morishita, Tsuboi, Tonai and Ueda (2004) J. Biol.

Massive accumulation of N-acylethanolamines after stroke. Cell signalling in acute cerebral ischemia?

We investigated levels and compositions of N-acylethanolamines (NAEs) and their precursors, N-acyl phosphatidylethanolamines (N-acyl PEs), in a rat stroke model applying striatal microdialysis for glutamate assay. Rats (n = 18) were treated with either intravenous saline (control), NMDA receptor antagonist MK801 (1 mg/kg), or CB1 receptor antagonist SR141716A (1 mg/kg) 30 min after permanent middle cerebral artery occlusion (MCAO). MK801 significantly attenuated the release of glutamate in the infarcted striatum (79 +/- 22 micromol/L) as compared with controls (322 +/- 104 micromol/L).

Region-dependent changes in endocannabinoid transmission in the brain of morphine-dependent rats.

It has been suggested recently that the endocannabinoid system might be a component of the brain reward circuitry and thus play a role not only in cannabinoid tolerance/dependence, but also in dependence/withdrawal to other drugs of abuse. Here we have examined the changes in endocannabinoid ligands and their receptors in different brain regions, with particular attention to those areas related to reinforcement processes, during dependence on the powerful addictive drug, morphine. Thus, we analysed the brain contents of N-arachidonoylethanolamine (anandamide, AEA), the first discovered endocannabinoid, in rats subjected to daily injections of increasing doses of morphine, according to a schedule designed to render the animals opiate-dependent.

Endocannabinoids induce ileitis in rats via the capsaicin receptor (VR1).

Intraluminal administration of the endocannabinoids N-arachidonoyl-ethanolamine (anandamide) and 2-arachidonoylglycerol (2-AG) causes inflammation similar to that caused by Clostridium difficile toxin A in the rat ileum. The effects of anandamide and 2-AG were significantly inhibited by pretreatment with the specific capsaicin receptor (vanilloid receptor subtype 1; VR1) antagonist capsazepine. Pretreatment with the CB1 and CB2 cannabinoid receptor antagonists N-piperidino-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-3-pyrazole-carboxamide (SR141716) and N-[1S)-endo-1,3,3-trimethylbicyclo[2.

Cell signaling by endocannabinoids and their congeners: questions of selectivity and other challenges.

The major endocannabinoids, anandamide (N-arachidonoylethanolamide, 20:4n-6 N-acylethanolamine) and 2-arachidonoylglycerol (2-AG) are structurally and functionally similar, but they are produced by different metabolic pathways and their levels must therefore be regulated by different mechanisms. Both endocannabinoids are accompanied by cannabinoid receptor-inactive, saturated and mono- or di-unsaturated congeners which can influence their metabolism and function. Here we review published data on the presence and production of anandamide and 2-AG and their congeners in mammalian cells and discuss this information in terms of their proposed signaling functions.

Anandamide and other N-acylethanolamines in human tumors.

Long-chain N-acylethanolamines (NAE), including the endocannabinoid, anandamide, accumulate in mammalian tissues under a variety of pathological conditions. They have also been shown to inhibit the growth of various cancer cell lines in vitro. Here, we report the presence, in widely differing amounts (3.