Variation in the relationship between odd isotopes of tin in mass-independent fractionation induced by the magnetic isotope effect.

Experimental results are presented showing the variation in the relationship between odd isotopes of tin (Sn) in mass-independent fractionation caused by the magnetic isotope effect (MIE), which has previously only been observed for mercury. These results are consistent with the trend predicted from the difference between the magnitudes of nuclear magnetic moments of odd isotopes with a nuclear spin. However, the correlation between odd isotopes in fractionation induced by the MIE for the reaction system used in this study (solvent extraction using a crown ether) was different from that reported for the photochemical reaction of methyltin. This difference between the two reaction systems is consistent with a theoretical prediction that the correlation between odd isotopes in fractionation induced by the MIE is controlled by the relationship between the spin conversion time and radical lifetime. The characteristic changes in the correlation between odd isotopes in fractionation induced by the MIE observed for Sn in this study provide a guideline for quantitatively determining fractionation patterns caused by the MIE for elements that have multiple isotopes with a nuclear spin. These results improve our understanding of the potential impact of the MIE on mass-independent fractionation observed in natural samples, such as meteorites, and analytical artifacts of high-precision isotope analysis for heavy elements.

Nonreciprocity and odd viscosity in chiral active fluids.

Odd viscosity couples stress to strain rate in a dissipationless way. It has been studied in plasmas under magnetic fields, superfluid [Formula: see text], quantum-Hall fluids, and recently in the context of chiral active matter. In most of these studies, odd terms in the viscosity obey Onsager reciprocal relations. Although this is expected in equilibrium systems, it is not obvious that Onsager relations hold in active materials. By directly coarse-graining the kinetic energy and independently using both the Poisson-bracket formalism and a kinetic theory derivation, we find that the appearance of a nonvanishing angular momentum density, which is a hallmark of chiral active materials, necessarily breaks Onsager reciprocal relations. This leads to a non-Hermitian dynamical matrix for the total hydrodynamic momentum and to the appearance of odd viscosity and other nondissipative contributions to the viscosity. Furthermore, by accounting for both the angular momentum density and interactions that lead to odd viscosity, we find regions in the parameter space in which 3D odd mechanical waves propagate and regions in which they are mechanically unstable. The lines separating these regions are continuous lines of exceptional points, suggesting a possible nonreciprocal phase transition.

Active metamaterials for realizing odd mass density.

Solids built out of active components have exhibited odd elastic stiffness tensors whose active moduli appear in the antisymmetric part and which give rise to non-Hermitian static and dynamic phenomena. Here, we present a class of active metamaterial featured with an odd mass density tensor whose asymmetric part arises from active and nonconservative forces. The odd mass density is realized using metamaterials with inner resonators connected by asymmetric and programmable feed-forward control on acceleration and active forces along the two perpendicular directions. The active forces produce unbalanced off-diagonal mass density coupling terms, leading to non-Hermiticity. The odd mass is then experimentally validated through a one-dimensional nonsymmetric wave coupling where propagating transverse waves are coupled with longitudinal ones whereas the reverse is forbidden. We reveal that the two-dimensional active metamaterials with the odd mass can perform in either energy-unbroken or energy-broken phases separated by exceptional points along principal directions of the mass density. The odd mass density contributes to the wave anisotropy in the energy-unbroken phase and directional wave energy gain in the energy-broken phase. We also numerically illustrate and experimentally demonstrate the two-dimensional wave propagation phenomena that arise from the odd mass in active solids. Finally, the existence of non-Hermitian skin effect is discussed in which boundaries host an extensive number of localized modes. It is our hope that the emergent concept of the odd mass can open up a new research platform for mechanical non-Hermitian system and pave the ways for developing next-generation wave steering devices.

Differential utilization of vitamin B12-dependent and independent pathways for propionate metabolism across human cells.

Propionic acid links the oxidation of branched-chain amino acids and odd-chain fatty acids to the TCA cycle. Gut microbes ferment complex fiber remnants, generating high concentrations of short chain fatty acids, acetate, propionate and butyrate, which are shared with the host as fuel sources. Analysis of vitamin B12-dependent propionate utilization in skin biopsy samples has been used to characterize and diagnose underlying inborn errors of cobalamin (or B12) metabolism. In these cells, the B12-dependent enzyme, methylmalonyl-CoA mutase (MMUT), plays a central role in funneling propionate to the TCA cycle intermediate, succinate. Our understanding of the fate of propionate in other cell types, specifically, the involvement of the ß-oxidation-like and methylcitrate pathways, is limited. In this study, we have used [14C]-propionate tracing in combination with genetic ablation or inhibition of MMUT, to reveal the differential utilization of the B12-dependent and independent pathways for propionate metabolism in fibroblast versus colon cell lines. We demonstrate that itaconate can be used as a tool to investigate MMUT-dependent propionate metabolism in cultured cell lines. While MMUT gates the entry of propionate carbons into the TCA cycle in fibroblasts, colon-derived cell lines exhibit a quantitatively significant or exclusive reliance on the ß-oxidation-like pathway. Lipidomics and metabolomics analyses reveal that propionate elicits pleiotropic changes, including an increase in odd-chain glycerophospholipids, and perturbations in the purine nucleotide cycle and arginine/nitric oxide metabolism. The metabolic rationale and the regulatory mechanisms underlying the differential reliance on propionate utilization pathways at a cellular, and possibly tissue level, warrant further elucidation.

Odd-even effect on the thermal conductivity of liquid crystalline epoxy resins.

Rapid developments in high-performance computing and high-power electronics are driving needs for highly thermal conductive polymers and their composites for encapsulants and interface materials. However, polymers typically have low thermal conductivities of ∼0.2 W/(m K). We studied the thermal conductivity of a series of epoxy resins cured by one diamine hardener and seven diepoxide monomers with different precise ethylene linker lengths (x = 2-8). We found pronounced odd-even effects of the ethylene linker length on the liquid crystalline order, mass density, and thermal conductivity. Epoxy resins with even x have liquid crystalline structure with the highest density of 1.44 g/cm3 and highest thermal conductivity of 1.0 W/(m K). Epoxy resins with odd x are amorphous with the lowest density of 1.10 g/cm3 and lowest thermal conductivity of 0.17 W/(m K). These findings indicate that controlling precise linker length in dense networks is a powerful route to molecular design of thermally conductive polymers.

Odd viscosity-induced Hall-like transport of an active chiral fluid.

Broken time-reversal and parity symmetries in active spinner fluids imply a nondissipative "odd viscosity," engendering phenomena unattainable in traditional passive or active fluids. Here we show that the odd viscosity itself can lead to a Hall-like transport when the active chiral fluid flows through a quenched matrix of obstacles, reminiscent of the anomalous Hall effect. The Hall-like velocity depends significantly on the spinner activity and longitudinal flow due to the interplay between odd viscosity and spinner-obstacle collisions. Our findings underscore the importance of odd viscosity in active chiral matter and elucidate its essential role in the anomalous Hall-like effect.

Unconventional Superconducting Diode Effects via Antisymmetry and Antisymmetry Breaking.

Symmetry breaking plays a pivotal role in unlocking intriguing properties and functionalities in material systems. For example, the breaking of spatial and temporal symmetries leads to a fascinating phenomenon: the superconducting diode effect. However, generating and precisely controlling the superconducting diode effect pose significant challenges. Here, we take a novel route with the deliberate manipulation of magnetic charge potentials to realize unconventional superconducting flux-quantum diode effects. We achieve this through suitably tailored nanoengineered arrays of nanobar magnets on top of a superconducting thin film. We demonstrate the vital roles of inversion antisymmetry and its breaking in evoking unconventional superconducting effects, namely a magnetically symmetric diode effect and an odd-parity magnetotransport effect. These effects are nonvolatilely controllable through in situ magnetization switching of the nanobar magnets. Our findings promote the use of antisymmetry (breaking) for initiating unconventional superconducting properties, paving the way for exciting prospects and innovative functionalities in superconducting electronics.

Quantum Interference and Coherent Population Trapping in a Double Quantum Dot.

Quantum interference is a natural consequence of wave-particle duality in quantum mechanics, and is widely observed at the atomic scale. One interesting manifestation of quantum interference is coherent population trapping (CPT), first proposed in three-level driven atomic systems and observed in quantum optical experiments. Here, we demonstrate CPT in a gate-defined semiconductor double quantum dot (DQD), with some unique twists as compared to the atomic systems. Specifically, we observe CPT in both driven and nondriven situations. We further show that CPT in a driven DQD could be used to generate adiabatic state transfer. Moreover, our experiment reveals a nontrivial modulation to the CPT caused by the longitudinal driving field, yielding an odd-even effect and a tunable CPT. Our results broaden the field of CPT, and open up the possibility of quantum simulation and quantum computation based on adiabatic passage in quantum dot systems.

Generation and characterisation of an Arabidopsis thaliana f3h/fls1/ans triple mutant that accumulates eriodictyol derivatives.

BACKGROUND: Flavonoids are plant specialised metabolites, which derive from phenylalanine and acetate metabolism. They possess a variety of beneficial characteristics for plants and humans. Several modification steps in the synthesis of tricyclic flavonoids cause for the amazing diversity of flavonoids in plants. The 2-oxoglutarate-dependent dioxygenases (2-ODDs) flavanone 3-hydroxylase (F3H, synonym FHT), flavonol synthase (FLS) and anthocyanidin synthase (ANS, synonym leucoanthocyanidin dioxygenase (LDOX)), catalyse oxidative modifications to the central C ring. They are highly similar and have been shown to catalyse, at least in part, each other's reactions. FLS and ANS have been identified as bifunctional enzymes in many species, including Arabidopsis thaliana, stressing the capability of plants to bypass missing or mutated reaction steps on the way to flavonoid production. However, little is known about such bypass reactions and the flavonoid composition of plants lacking all three central flavonoid 2-ODDs. RESULTS: To address this issue, we generated a f3h/fls1/ans mutant, as well as the corresponding double mutants and investigated the flavonoid composition of this mutant collection. The f3h/fls1/ans mutant was further characterised at the genomic level by analysis of a nanopore DNA sequencing generated genome sequence assembly and at the transcriptomic level by RNA-Seq analysis. The mutant collection established, including the novel double mutants f3h/fls1 and f3h/ans, was used to validate and analyse the multifunctionalities of F3H, FLS1, and ANS in planta. Metabolite analyses revealed the accumulation of eriodictyol and additional glycosylated derivatives in mutants carrying the f3h mutant allele, resulting from the conversion of naringenin to eriodictyol by flavonoid 3'-hydroxylase (F3'H) activity. CONCLUSIONS: We describe the in planta multifunctionality of the three central flavonoid 2-ODDs from A. thaliana and identify a bypass in the f3h/fls1/ans triple mutant that leads to the formation of eriodictyol derivatives. As (homo-)eriodictyols are known as bitter taste maskers, the annotated eriodictyol (derivatives) and in particular the observations made on their in planta production, could provide valuable insights for the creation of novel food supplements.

Odd-Even Law Mediated Supramolecular Chirality of Luminescent Dipeptides for Chiroptical Energy Transfer.

Inherent luminescent short peptides essentially provide opportunities to rationally manipulate supramolecular chirality and chiral luminescence. Herein, a facile protocol to construct a series of naphthalimide-appended dipeptides is reported that show ultrasound wave-activated supramolecular chirality regulated by odd-even law. Naphthalimide luminophores are conjugated to the dipeptide skeleton with variable alkyl spacers. The presence of tyrosine interferes the kinetic aggregation into achiral nanoparticles without chirality transfer to supramolecular scale. However, ultrasound treatment initiates the nanoparticle-to-helix transition accompanied with the appeared chiral optics, including Cotton effect and circularly polarized luminescence (CPL). The supramolecular chiral parameters, including handedness of helices and chiroptical behaviors, follow the odd-even law of alkyl spacers in dipeptides bearing non-substituted naphthalimides. The amine-substitution boosted the quantum yields of dipeptide whereas no odd-even effect. The two types of dipeptides constituted ideal energy transfer pairs that enable the efficient energy transfer as well as the transportation of odd-even law to dipeptides containing substituted naphthalimides. This work sheds light on the construction of luminescent dipeptides with applications in precise control over chirality transportation and chiral luminescence.

Metabolic engineering of Saccharomyces cerevisiae for de novo production of odd-numbered medium-chain fatty acids.

Odd-numbered fatty acids (FAs) have been widely used in nutrition, agriculture, and chemical industries. Recently, some studies showed that they could be produced from bacteria or yeast, but the products are almost exclusively odd-numbered long-chain FAs. Here we report the design and construction of two biosynthetic pathways in Saccharomyces cerevisiae for de novo production of odd-numbered medium-chain fatty acids (OMFAs) via ricinoleic acid and 10-hydroxystearic acid, respectively. The production of OMFAs was enabled by introducing a hydroxy fatty acid cleavage pathway, including an alcohol dehydrogenase from Micrococcus luteus, a Baeyer-Villiger monooxygenase from Pseudomonas putida, and a lipase from Pseudomonas fluorescens. These OMFA biosynthetic pathways were optimized by eliminating the rate-limiting step, generating heptanoic acid, 11-hydroxyundec-9-enoic acid, nonanoic acid, and 9-hydroxynonanoic acid at 7.83 mg/L, 9.68 mg/L, 9.43 mg/L and 13.48 mg/L, respectively. This work demonstrates the biological production of OMFAs in a sustainable manner in S. cerevisiae.

Dietary habits and plasma lipid concentrations in a general Japanese population.

INTRODUCTION: Accumulating data on the associations between food consumption and lipid composition in the body is essential for understanding the effects of dietary habits on health. OBJECTIVES: As part of omics research in the Tohoku Medical Megabank Community-Based Cohort Study, this study sought to reveal the dietary impact on plasma lipid concentration in a Japanese population. METHODS: We conducted a correlation analysis of food consumption and plasma lipid concentrations measured using mass spectrometry, for 4032 participants in Miyagi Prefecture, Japan. RESULTS: Our analysis revealed 83 marked correlations between six food categories and the concentrations of plasma lipids in nine subclasses. Previously reported associations, including those between seafood consumption and omega-3 fatty acids, were validated, while those between dairy product consumption and odd-carbon-number fatty acids (odd-FAs) were validated for the first time in an Asian population. Further analysis suggested that dairy product consumption is associated with odd-FAs via sphingomyelin (SM), which suggests that SM is a carrier of odd-FAs. These results are important for understanding odd-FA metabolism with regards to dairy product consumption. CONCLUSION: This study provides insight into the dietary impact on plasma lipid concentration in a Japanese population.

The Interplay of Spacer Chirality and Parity in Mesogenic Dimers.

Introducing chirality into soft materials, including liquid crystals (LCs), profoundly impacts their self-organization and physical properties. In this study, we synthesized a novel series of LC dimers with a chiral center as part of their flexible spacer. The dimers were prepared in racemic and enantiomerically pure forms. Their spacer length and parity were varied to investigate the effect of spacer chirality and parity on mesomorphic behavior and on chiral induction in the nematic phase of achiral mesogens. Our results show that the even-membered chiral dimers only have chiral nematic phases. In contrast, the odd-membered dimers display rich mesomorphism, including the intriguing blue phase (BP) and chiral form of the twist-bend nematic phase (N*TB). The observed significant difference in the 3D surface morphology between the racemic and chiral forms of the N*TB phase suggests that the chiral moiety in the spacer promotes a chiral hierarchy. Furthermore, the chiral dimers show a prominent odd-even effect in the helical twisting power in nematic hosts. These findings highlight the importance of the position of the chiral group within the dimeric molecule and provide new insights into how intrinsic chirality in the spacer affects the overall structural chirality.

Moving forward. Use of the START NOW skills training program for female youth with ODD and CD - a commentary on Stadler et al. (2024).

Female youth with oppositional defiant disorder (ODD) and conduct disorder (CD) are an under studied and underserved population at high risk for poor adjustment in later life. Stadler et al. (2024) attempt to redress this situation for adolescent females with CD or ODD with an adapted version of the skills training program START NOW. They describe the results of an ambitious randomized control trial, comparing START NOW with standard care in youth welfare settings in Germany, Switzerland, and The Netherlands. The findings appear promising, but the paper is especially valuable for the spotlight it shines on the needs of this underserved population and those caring for them, together with the importance of undertaking such trials despite their challenges. This commentary seeks to encourage readers to engage with the START NOW trial.

Filling the Gaps: Using Synthetic Low-Altitude Aerial Images to Increase Operational Design Domain Coverage.

A key necessity for the safe and autonomous flight of Unmanned Aircraft Systems (UAS) is their reliable perception of the environment, for example, to assess the safety of a landing site. For visual perception, Machine Learning (ML) provides state-of-the-art results in terms of performance, but the path to aviation certification has yet to be determined as current regulation and standard documents are not applicable to ML-based components due to their data-defined properties. However, the European Union Aviation Safety Agency (EASA) published the first usable guidance documents that take ML-specific challenges, such as data management and learning assurance, into account. In this paper, an important concept in this context is addressed, namely the Operational Design Domain (ODD) that defines the limitations under which a given ML-based system is designed to operate and function correctly. We investigated whether synthetic data can be used to complement a real-world training dataset which does not cover the whole ODD of an ML-based system component for visual object detection. The use-case in focus is the detection of humans on the ground to assess the safety of landing sites. Synthetic data are generated using the methods proposed in the EASA documents, namely augmentations, stitching and simulation environments. These data are used to augment a real-world dataset to increase ODD coverage during the training of Faster R-CNN object detection models. Our results give insights into the generation techniques and usefulness of synthetic data in the context of increasing ODD coverage. They indicate that the different types of synthetic images vary in their suitability but that augmentations seem to be particularly promising when there is not enough real-world data to cover the whole ODD. By doing so, our results contribute towards the adoption of ML technology in aviation and the reduction of data requirements for ML perception systems.

A comparison of conventional and resampled personal reliability in detecting careless responding.

Detecting careless responding in survey data is important to ensure the credibility of study findings. Of several available detection methods, personal reliability (PR) is one of the best-performing indices. Curran, Journal of Experimental Social Psychology, 66, 4-19, (2016) proposed a resampled version of personal reliability (RPR). Compared to the conventional PR or even-odd consistency, in which just one set of scale halves is used, RPR is based on repeated calculation of PR across several randomly rearranged sets of scale halves. RPR should therefore be less affected than PR by random errors that may occur when a specific set of scale half pairings is used for the PR calculation. In theory, RPR should outperform PR, but it remains unclear whether it in fact does, and under what conditions the potential gain in detection accuracy is the most pronounced. We conducted two studies: a simulation study examined the performance of the conventional PR and RPR in detecting simulated careless responding, and a real data example study analyzed their performance when detecting human-generated careless responding. In both studies, RPR turned out to be a significantly better careless response indicator than PR. The results also revealed that using 25 resamples for the RPR computation is sufficient to obtain the expected gain in detection accuracy over the conventional PR. We therefore recommend using RPR instead of the conventional PR when screening questionnaire data for careless responding.

Even and Odd Cat States of Two and Three Qubits in the Probability Representation of Quantum Mechanics.

We derive the probability representation of even and odd cat states of two and three qubits. These states are even and odd superpositions of spin-1/2 eigenstates corresponding to two opposite directions along the z axis. The probability representation of even and odd cat states of an oscillating spin-1/2 particle is also discussed. The exact formulas for entangled probability distributions describing density matrices of all these states are obtained.

Equivalent carbon number-based targeted odd-chain fatty acyl lipidomics reveals triacylglycerol profiling in clinical colon cancer.

Odd-chain FAs (OCFAs) are present in very low level at nearly 1% of total FAs in human plasma, and thus, their functions were usually ignored. Recent epidemiological studies have shown that OCFAs are inversely associated with a variety of disease risks. However, the contribution of OCFAs incorporated into complex lipids remains elusive. Here, we developed a targeted odd-chain fatty acyl-containing lipidomics method based on equivalent carbon number and retention time prediction. The method displayed good reproducibility and robustness as shown by peak width at half height within 0.7 min and coefficient of variation under 20%. A total number of 776 lipid species with odd-chain fatty acyl residues could be detected in the ESI mode of reverse-phase LC-MS, of which 309 lipids were further validated using multiple reaction monitoring transitions. Using this method, we quantified odd-chain fatty acyl-containing lipidome in tissues from 12 colon cancer patients, revealing the remodeling of triacylglycerol. The dynamics of odd-chain fatty acyl lipids were further consolidated by the association with genomic and proteomic features of altered catabolism of branched-chain amino acids and triacylglycerol endogenous synthesis in colon cancer. This lipidomics approach will be applicable for screening of dysregulated odd-chain fatty acyl lipids, which enriches and improves the methods for diagnosis and prognosis evaluation of cancer using lipidomics.

Cellular Prion protein moonlights vascular smooth muscle cell fate: Surveilled by trophoblast cells.

Uterine spiral artery remodeling (uSAR) is a hallmark of hemochorial placentation. Compromised uSAR leads to adverse pregnancy outcomes. Salient developmental events involved in uSAR are active areas of research and include (a) trophendothelial cell invasion into the spiral arteries, selected demise of endothelial cells; (b) de-differentiation of vascular smooth muscle cells (VSMC); and (c) migration and/or death of VSMCs surrounding spiral arteries. Here we demonstrated that cellular prion (PRNP) is expressed in the rat metrial gland, the entry point of spiral arteries with the highest expression on E16.5, the day at which trophoblast invasion peaks. PRNP is expressed in VSMCs that drift away from the arterial wall. RNA interference of Prnp functionally restricted migration and invasion of rat VSMCs. Furthermore, PRNP interacted with two migration-promoting factors, focal adhesion kinase (FAK) and platelet-derived growth factor receptor-ß (PDGFR-ß), forming a ter-molecular complex in both the metrial gland and A7r5 cells. The presence of multiple putative binding site of odd skipped related-1 (OSR1) transcription factor on the Prnp promoter was observed using in silico promoter analysis. Ectopic overexpression of OSR1 increased, and knockdown of OSR1 decreased expression of PRNP in VSMCs. Coculture of VSMCs with rat primary trophoblast cells decreased the levels of OSR1 and PRNP. Interestingly, PRNP knockdown led to apoptotic death in ~9% of VSMCs and activated extrinsic apoptotic pathways. PRNP interacts with TRAIL-receptor DR4 and protects VSMCs from TRAIL-mediated apoptosis. These results highlight the biological functions of PRNP in VSMC cell-fate determination during uteroplacental development, an important determinant of healthy pregnancy outcome.

The mitochondrial genome of the mountain wooly tapir, Tapirus pinchaque and a formal test of the effect of altitude on the adaptive evolution of mitochondrial protein coding genes in odd-toed ungulates.

BACKGROUND: The harsh conditions of high-altitude environments are known to drive the evolution of physiological and morphological traits in endothermic animals. These conditions are expected to result in the adaptive evolution of protein coding genes encoded in mitochondrial genomes that are vital for the oxidative phosphorylation pathway. In this study, we formally tested for signatures of adaptive evolution on mitochondrial protein coding genes in Tapirus pinchaque and other odd-toed ungulates inhabiting high-elevation environments. RESULTS: The AT-rich mitochondrial genome of T. pinchaque is 16,750 bp long. A phylomitogenomic analysis supports the monophyly of the genus Tapirus and families in the Perissodactyla. The ratio of non-synonymous to synonymous substitutions demonstrated that all mitochondrial genes undergo purifying selection in T. pinchaque and other odd ungulates living at high elevations. Over this negative background selection, Branch Models suggested that cox3 and nad6 might be undergoing stronger purifying selection than other mitochondrial protein coding genes. Furthermore, Site Models suggested that one and four sites in nad2 and nad5, respectively, could be experiencing positive selection. However, these results were supported by Likelihood Ratio Tests but not Bayesian Empirical Bayes posterior probabilities. Additional analyses (in DataMonkey) indicated a relaxation of selection strength in nad6, evidence of episodic diversifying selection in cob, and revealed episodic positive/diversifying selection signatures for two sites in nad1, and one site each in nad2 and nad4. CONCLUSION: The mitochondrial genome of T. pinchaque is an important genomic resource for conservation of this species and this study contributes to the understanding of adaptive evolution of mitochondrial protein coding genes in odd-toed ungulates inhabiting high-altitude environments.