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This work is concerned with the fusion of inertial measurements (accelerations and angular velocities) with imagery data (feature points extracted in a video stream) in a recursive bundle adjustment framework for indoor position and attitude estimation. Recursive processing is achieved by a combination of local submaps and the Schur complement. The Schur complement is used to reduce the problem size at regular intervals while retaining the information provided by past measurements. Local submaps provide a way to propagate the gauge constraints and thereby to alleviate the detrimental effects of linearization errors in the prior. Though the presented technique is not real-time capable in its current implementation, it can be employed to process arbitrarily long trajectories. The presented system is evaluated by comparing the estimated trajectory of the system with a reference trajectory of a prism attached to the system, which was recorded by a total station. [ABSTRACT FROM AUTHOR]

The spectral energy distributions of signals picked up by endocardial, atrial and ventricular electrodes have been investigated. The results show similar spectral distributions for P-waves and QRS-complexes with maximum spectral densities at frequencies between 10 and 30 Hz. [ABSTRACT FROM AUTHOR]

Erythropoietin (EPO) is pivotal in regulating red blood cell (erythrocyte) concentrations and is primarily synthesized in the kidney. Recent research has unveiled a possible link between elevated circulating concentrations of ketone bodies (KB) and circulating EPO concentrations; however, it is not known whether nutritionally induced endogenous ketogenesis can be a stimulus to induce EPO in humans. Therefore, this study aimed to assess whether acute and chronic intake of medium-chain fatty acid-containing triacylglycerol (MCT), which rapidly enhances endogenous circulating KB, would elevate circulating EPO concentrations in humans, as indicated by prior work with exogenous KB administration. The study followed a crossover design involving 16 young men undergoing two 8-day MCT or energy-matched long-chain fatty acid-containing triacylglycerol (LCT) interventions in a randomized order. Five-hour test days were performed before and after each intervention, in which circulating KB and EPO concentrations as well as hematological parameters were assessed. Acute intake of MCT yielded a 222% sustained 5-h elevation in KB concentrations compared with LCT-with notable peak values of 0.7 ± 0.1 mmol·L -1 (312% above basal values). Remarkably, within just 8 days of daily MCT intake an impressive 38% increase in basal, fasting plasma EPO concentrations (7.19 ± 1.14 to 9.91 ± 1.25 mIU·mL -1 ) was demonstrated. In conclusion, this study unveils a novel physiological stimulus of circulating EPO concentrations in humans, potentially offering a new dietary approach to counter anemia in cardiovascular diseases. NEW & NOTEWORTHY This study is the first to assess the effects of nutritionally induced ketogenesis by acute and subchronic intake of medium-chain fatty acids on plasma erythropoietin concentrations. Medium-chain fatty acid intake increases postprandial ketone body concentrations and within only 8 days of daily intake substantially enhances basal plasma erythropoietin concentrations in young men. We therefore reveal a dietary stimulus of endogenous circulating erythropoietin concentrations in humans, with the potential to counter anemia in cardiovascular diseases.

Metabolic flexibility in skeletal muscle is essential for maintaining healthy glucose and lipid metabolism, and its dysfunction is closely linked to metabolic diseases. Exercise enhances metabolic flexibility, making it an important tool for discovering mechanisms that promote metabolic health. Here we show that pantothenate kinase 4 (PanK4) is a new conserved exercise target with high abundance in muscle. Muscle-specific deletion of PanK4 impairs fatty acid oxidation which is related to higher intramuscular acetyl-CoA and malonyl-CoA levels. Elevated acetyl-CoA levels persist regardless of feeding state and are associated with whole-body glucose intolerance, reduced insulin-stimulated glucose uptake in glycolytic muscle, and impaired glucose uptake during exercise. Conversely, increasing PanK4 levels in glycolytic muscle lowers acetyl-CoA and enhances glucose uptake. Our findings highlight PanK4 as an important regulator of acetyl-CoA levels, playing a key role in both muscle lipid and glucose metabolism., Competing Interests: Competing interests: M.H.T. delivered a scientific lecture for Böhringer Ingelheim Pharma GmbH & Co. KG (2024), AstraZeneca GmbH (2024), Lilly Deutschland GmbH (2024) and Novo Nordisk Pharma GmbH (2024). He is co-founder of the biotech startups Ghrelco and Bluewater Biotech (2024). As CEO and CSO of Helmholtz Munich, M.H.T. is co-responsible for countless collaborations of the employees with a multitude of companies and institutions, worldwide. In this capacity, he discusses potential projects with and has signed/signs contracts for the centers institute(s) related to research collaborations worldwide, including but not limited to pharmaceutical corporations like Boehringer Ingelheim, Novo Nordisk, Roche Diagnostics, Arbormed, Eli Lilly, SCG Cell Therapy and others. As the CEO of Helmholtz Munich, he was/is further overall responsible for commercial technology transfer activities. M.H.T. confirms that to the best of his knowledge none of the above funding sources or collaborations were involved in or had an influence on the preparation of this manuscript. The remaining authors declare no competing interests., (© 2025. The Author(s).)

Several health-beneficial effects are associated with intake of medium-chain triacylglycerol (MCT); however, the underlying mechanisms are unknown. Furthermore, it remains uncertain whether the acute metabolic effects of MCT differ between lean individuals and individuals with obesity-and whether these effects are sustained following chronic intake. This study aimed to elucidate the postprandial physiological and metabolic effects of MCT before and after 8 days intake compared with intake of energy-matched triacylglycerol consisting of long-chain fatty acids (long-chain triacylglycerols, LCT) using a randomized cross-over design in lean individuals ( n = 8) and individuals with obesity ( n = 8). The study revealed that consumption of MCT increased ketogenesis and metabolic rate while lowering blood glucose levels over 5 h. The hypoglycemic action of MCT intake was accompanied by a concomitant transient increase in plasma insulin and glucagon levels. Interestingly, the effects on ketogenesis, metabolic rate, and glycemia were preserved in individuals with obesity and sustained after 8 days of daily supplementation. Lipidomic plasma analysis in lean individuals ( n = 4) showed that a part of the ingested MCT bypasses the liver and enters the systemic circulation as medium-chain fatty acids (MCFAs). The findings suggest that MCFAs, along with ketone bodies from the liver, may act as signaling molecules and/or substrates in the peripheral tissues, thereby contributing to the effects of MCT intake. In summary, these findings underscore the health benefits of MCT in metabolically compromised individuals after daily supplementation. Moreover, we uncover novel aspects of MCFA biology, providing insights into how these fatty acids orchestrate physiological effects in humans. NEW & NOTEWORTHY We reveal that medium-chain triacylglycerol (MCT) intake increases postprandial ketogenesis and metabolic rate and reduces plasma glucose levels in humans. Notably, these responses persist in individuals with obesity and are maintained following chronic MCT supplementation. Some medium-chain fatty acids entered the circulation, suggesting that these, together with ketone bodies, act as signaling molecules/substrates in peripheral tissues. The findings highlight health beneficial effects of dietary MCT in individuals with obesity and reveal new insights into lipid biology.

Recent research has identified growth differentiation factor 15 (GDF15) as a crucial factor in various physiological and pathological processes, particularly in energy balance regulation. While the role of GDF15 in modulating energy metabolism through hindbrain GDNF family receptor alpha-like (GFRAL) signaling has been extensively studied, emerging evidence suggests direct peripheral metabolic actions of GDF15. Using knockout mouse models, we investigated GDF15 and GFRAL's roles in adipose tissue metabolism. Our findings indicate that C57BL/6/129/SvJ Gdf15-KO mice exhibit impaired expression of de novo lipogenesis enzymes in subcutaneous adipose tissue (sWAT). In contrast, C57BL/6J Gfral-KO mice showed no impairments compared to wild-type (WT) littermates. RNA-Seq analysis of sWAT in Gdf15-KO mice revealed a broad downregulation of genes involved in lipid metabolism. Importantly, our study uncovered sex-specific effects, with females being more affected by GDF15 loss than males. Additionally, we observed a fasting-induced upregulation of GDF15 gene expression in sWAT of both mice and humans, reinforcing this factor's role in adipose tissue lipid metabolism. In conclusion, our research highlights an essential role for GDF15 in sWAT lipid metabolic homeostasis. These insights enhance our understanding of GDF15's functions in adipose tissue physiology and underscore its potential as a therapeutic target for metabolic disorders., (© 2024. The Author(s).)

Growth differentiation factor 15 (GDF15) is a member of the transforming growth factor-β (TGF-β) superfamily. Despite its identification over 20 years ago, the functions of GDF15 remain complex and not fully elucidated. Its concentration in plasma varies widely depending on the physiological and pathophysiological state of the organism. GDF15 has been described to regulate food intake and insulin sensitivity in rodents via the GDNF family receptor α-like (GFRAL) receptor, and to be elevated in pregnancy and many disease states and decreased in physically fit individuals. We discuss the latest developments in the regulation of GDF15 secretion and its diverse physiological effects, and touch upon possible GFRAL-independent effects of GDF15. In addition, we discuss the effects of proteins and peptides derived from the same precursor protein as GDF15., Competing Interests: Declaration of interests The authors declare no conflicts of interest, (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Objective: Dietary medium-chain fatty acids (MCFAs), characterized by chain lengths of 8-12 carbon atoms, have been proposed to have beneficial effects on glucose and lipid metabolism, yet the underlying mechanisms remain elusive. We hypothesized that MCFA intake benefits metabolic health by inducing the release of hormone-like factors., Methods: The effects of chow diet, high-fat diet rich in long-chain fatty acids (LCFA HFD) fed ad libitum or pair-fed to a high-fat diet rich in MCFA (MCFA HFD) on glycemia, hepatic gene expression, circulating fibroblast growth factor 21 (FGF21), and liver fat content in both wildtype and Fgf21 knockout mice were investigated. The impact of a single oral dose of an MCFA-rich oil on circulating FGF21 and hepatic Fgf21 mRNA expression was assessed. In flag-tagged Crebh knockin mice and liver-specific Crebh knockout mice, fed LCFA HFD or MCFA HFD, active hepatic CREBH and hepatic Fgf21 mRNA abundance were determined, respectively., Results: MCFA HFD improves glucose tolerance, enhances glucose clearance into brown adipose tissue, and prevents high-fat diet-induced hepatic steatosis in wildtype mice. These benefits are associated with increased liver expression of CREBH target genes (Apoa4 and Apoc2), including Fgf21. Both acute and chronic intake of dietary MCFAs elevate circulating FGF21. Augmented hepatic Fgf21 mRNA following MCFA HFD intake is accompanied by higher levels of active hepatic CREBH; and MCFA-induced hepatic Fgf21 expression is blocked in mice lacking Crebh. Notably, while feeding male and female Fgf21 wildtype mice MCFA HFD results in reduced liver triacylglycerol (TG) levels, this liver TG-lowering effect is blunted in Fgf21 knockout mice fed MCFA HFD. The reduction in liver TG levels observed with MCFA HFD was independent of weight loss., Conclusions: Dietary MCFAs reduce liver fat accumulation via activation of a CREBH-FGF21 signaling axis., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: C.C. is co-founder of Ousia Pharma ApS, a biotech company developing therapeutics for obesity. C.C. is also on the editorial board of Molecular Metabolism. The remaining authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier GmbH.. All rights reserved.)

Dietary short- and medium-chain fatty acids have been shown to elevate circulating ketone bodies and confer metabolic health benefits. Cow milk fat contains these lipids in a balanced mix but in relatively low concentrations. Enriching them could amplify health benefits of dairy products. Here, we used a volatility-based workflow to produce milk fat with a 2-fold enrichment of medium- and short-chain fatty acids (referred to as MSFAT). Our proof-of-concept studies in mice demonstrated that intake of MSFAT increased circulating ketone bodies, reduced blood glucose levels, and suppressed food intake. In humans, ingestion of MSFAT resulted in increased circulating ketone bodies, trended to attenuate ( p = 0.07) postprandial glucose excursion, and acutely elevated energy expenditure. Our findings show that milk products enriched with MSFAT may hold significant metabolic advantages.

Mass-deployable implementations for quantum communication require compact, reliable, and low-cost hardware solutions for photon generation, control and analysis. We present a fiber-pigtailed hybrid photonic circuit comprising nonlinear waveguides for photon-pair generation and a polymer interposer reaching 68 dB of pump suppression and photon separation based on a polarizing beam splitter with > 25 dB polarization extinction ratio. The optical stability of the hybrid assembly enhances the quality of the entanglement, and the efficient background suppression and photon routing further reduce accidental coincidences. We thus achieve a 96 - 8 + 3 % concurrence and a 96 - 5 + 2 % fidelity to a Bell state. The generated telecom-wavelength, time-bin entangled photon pairs are ideally suited for distributing Bell pairs over fiber networks with low dispersion., (© 2024. The Author(s).)