Search

Your search keyword '"Hoos, A."' showing total 1,997 results
Start Over Author "Hoos, A." Publication Year Range Last 10 years
1,997 results on '"Hoos, A."'

1. ARLBench: Flexible and Efficient Benchmarking for Hyperparameter Optimization in Reinforcement Learning

Author

Becktepe, Jannis, Dierkes, Julian, Benjamins, Carolin, Mohan, Aditya, Salinas, David, Rajan, Raghu, Hutter, Frank, Hoos, Holger, Lindauer, Marius, and Eimer, Theresa

Subjects
Computer Science - Machine Learning
Abstract

Hyperparameters are a critical factor in reliably training well-performing reinforcement learning (RL) agents. Unfortunately, developing and evaluating automated approaches for tuning such hyperparameters is both costly and time-consuming. As a result, such approaches are often only evaluated on a single domain or algorithm, making comparisons difficult and limiting insights into their generalizability. We propose ARLBench, a benchmark for hyperparameter optimization (HPO) in RL that allows comparisons of diverse HPO approaches while being highly efficient in evaluation. To enable research into HPO in RL, even in settings with low compute resources, we select a representative subset of HPO tasks spanning a variety of algorithm and environment combinations. This selection allows for generating a performance profile of an automated RL (AutoRL) method using only a fraction of the compute previously necessary, enabling a broader range of researchers to work on HPO in RL. With the extensive and large-scale dataset on hyperparameter landscapes that our selection is based on, ARLBench is an efficient, flexible, and future-oriented foundation for research on AutoRL. Both the benchmark and the dataset are available at https://github.com/automl/arlbench., Comment: Accepted at the 17th European Workshop on Reinforcement Learning

Published
2024

2. Edge-Based Graph Component Pooling

Author

Snelleman, T., Renting, B. M., Hoos, H. H., and van Rijn, J. N.

Subjects
Computer Science - Machine Learning
Abstract

Graph-structured data naturally occurs in many research fields, such as chemistry and sociology. The relational information contained therein can be leveraged to statistically model graph properties through geometrical deep learning. Graph neural networks employ techniques, such as message-passing layers, to propagate local features through a graph. However, message-passing layers can be computationally expensive when dealing with large and sparse graphs. Graph pooling operators offer the possibility of removing or merging nodes in such graphs, thus lowering computational costs. However, pooling operators that remove nodes cause data loss, and pooling operators that merge nodes are often computationally expensive. We propose a pooling operator that merges nodes so as not to cause data loss but is also conceptually simple and computationally inexpensive. We empirically demonstrate that the proposed pooling operator performs statistically significantly better than edge pool on four popular benchmark datasets while reducing time complexity and the number of trainable parameters by 70.6% on average. Compared to another maximally powerful method named Graph Isomporhic Network, we show that we outperform them on two popular benchmark datasets while reducing the number of learnable parameters on average by 60.9%., Comment: 15 pages, presented at 21st International Workshop on Mining and Learning with Graphs, AstraZenica Bio & Healthcare award Paper, ECML PKDD 2024 Vilnius

Published
2024

3. Combining Automated Optimisation of Hyperparameters and Reward Shape

Author

Dierkes, Julian, Cramer, Emma, Hoos, Holger H., and Trimpe, Sebastian

Subjects
Computer Science - Machine Learning, Computer Science - Artificial Intelligence
Abstract

There has been significant progress in deep reinforcement learning (RL) in recent years. Nevertheless, finding suitable hyperparameter configurations and reward functions remains challenging even for experts, and performance heavily relies on these design choices. Also, most RL research is conducted on known benchmarks where knowledge about these choices already exists. However, novel practical applications often pose complex tasks for which no prior knowledge about good hyperparameters and reward functions is available, thus necessitating their derivation from scratch. Prior work has examined automatically tuning either hyperparameters or reward functions individually. We demonstrate empirically that an RL algorithm's hyperparameter configurations and reward function are often mutually dependent, meaning neither can be fully optimised without appropriate values for the other. We then propose a methodology for the combined optimisation of hyperparameters and the reward function. Furthermore, we include a variance penalty as an optimisation objective to improve the stability of learned policies. We conducted extensive experiments using Proximal Policy Optimisation and Soft Actor-Critic on four environments. Our results show that combined optimisation significantly improves over baseline performance in half of the environments and achieves competitive performance in the others, with only a minor increase in computational costs. This suggests that combined optimisation should be best practice., Comment: Published in the Reinforcement Learning Journal 2024

Published
2024

4. Towards General Negotiation Strategies with End-to-End Reinforcement Learning

Author

Renting, Bram M., Moerland, Thomas M., Hoos, Holger H., and Jonker, Catholijn M.

Subjects
Computer Science - Multiagent Systems, Computer Science - Machine Learning, I.2.11, I.2.6
Abstract

The research field of automated negotiation has a long history of designing agents that can negotiate with other agents. Such negotiation strategies are traditionally based on manual design and heuristics. More recently, reinforcement learning approaches have also been used to train agents to negotiate. However, negotiation problems are diverse, causing observation and action dimensions to change, which cannot be handled by default linear policy networks. Previous work on this topic has circumvented this issue either by fixing the negotiation problem, causing policies to be non-transferable between negotiation problems or by abstracting the observations and actions into fixed-size representations, causing loss of information and expressiveness due to feature design. We developed an end-to-end reinforcement learning method for diverse negotiation problems by representing observations and actions as a graph and applying graph neural networks in the policy. With empirical evaluations, we show that our method is effective and that we can learn to negotiate with other agents on never-before-seen negotiation problems. Our result opens up new opportunities for reinforcement learning in negotiation agents., Comment: Accepted at the Reinforcement Learning Conference (RLC) 2024

Published
2024

5. Automated Design of Linear Bounding Functions for Sigmoidal Nonlinearities in Neural Networks

Author

König, Matthias, Zhang, Xiyue, Hoos, Holger H., Kwiatkowska, Marta, and van Rijn, Jan N.

Subjects
Computer Science - Machine Learning, Computer Science - Artificial Intelligence, Computer Science - Logic in Computer Science
Abstract

The ubiquity of deep learning algorithms in various applications has amplified the need for assuring their robustness against small input perturbations such as those occurring in adversarial attacks. Existing complete verification techniques offer provable guarantees for all robustness queries but struggle to scale beyond small neural networks. To overcome this computational intractability, incomplete verification methods often rely on convex relaxation to over-approximate the nonlinearities in neural networks. Progress in tighter approximations has been achieved for piecewise linear functions. However, robustness verification of neural networks for general activation functions (e.g., Sigmoid, Tanh) remains under-explored and poses new challenges. Typically, these networks are verified using convex relaxation techniques, which involve computing linear upper and lower bounds of the nonlinear activation functions. In this work, we propose a novel parameter search method to improve the quality of these linear approximations. Specifically, we show that using a simple search method, carefully adapted to the given verification problem through state-of-the-art algorithm configuration techniques, improves the average global lower bound by 25% on average over the current state of the art on several commonly used local robustness verification benchmarks.

Published
2024

10. Competitions in AI -- Robustly Ranking Solvers Using Statistical Resampling

Author

Fawcett, Chris, Vallati, Mauro, Hoos, Holger H., and Gerevini, Alfonso E.

Subjects
Computer Science - Artificial Intelligence
Abstract

Solver competitions play a prominent role in assessing and advancing the state of the art for solving many problems in AI and beyond. Notably, in many areas of AI, competitions have had substantial impact in guiding research and applications for many years, and for a solver to be ranked highly in a competition carries considerable weight. But to which extent can we expect competition results to generalise to sets of problem instances different from those used in a particular competition? This is the question we investigate here, using statistical resampling techniques. We show that the rankings resulting from the standard interpretation of competition results can be very sensitive to even minor changes in the benchmark instance set used as the basis for assessment and can therefore not be expected to carry over to other samples from the same underlying instance distribution. To address this problem, we introduce a novel approach to statistically meaningful analysis of competition results based on resampling performance data. Our approach produces confidence intervals of competition scores as well as statistically robust solver rankings with bounded error. Applied to recent SAT, AI planning and computer vision competitions, our analysis reveals frequent statistical ties in solver performance as well as some inversions of ranks compared to the official results based on simple scoring.

Published
2023

11. Q(D)O-ES: Population-based Quality (Diversity) Optimisation for Post Hoc Ensemble Selection in AutoML

Author

Purucker, Lennart, Schneider, Lennart, Anastacio, Marie, Beel, Joeran, Bischl, Bernd, and Hoos, Holger

Subjects
Computer Science - Machine Learning, Computer Science - Neural and Evolutionary Computing, I.2.6, I.5.1
Abstract

Automated machine learning (AutoML) systems commonly ensemble models post hoc to improve predictive performance, typically via greedy ensemble selection (GES). However, we believe that GES may not always be optimal, as it performs a simple deterministic greedy search. In this work, we introduce two novel population-based ensemble selection methods, QO-ES and QDO-ES, and compare them to GES. While QO-ES optimises solely for predictive performance, QDO-ES also considers the diversity of ensembles within the population, maintaining a diverse set of well-performing ensembles during optimisation based on ideas of quality diversity optimisation. The methods are evaluated using 71 classification datasets from the AutoML benchmark, demonstrating that QO-ES and QDO-ES often outrank GES, albeit only statistically significant on validation data. Our results further suggest that diversity can be beneficial for post hoc ensembling but also increases the risk of overfitting., Comment: 10 pages main paper, 24 pages references and appendix, 4 figures, 16 subfigures, 13 tables, to be published in: International Conference on Automated Machine Learning 2023; affiliations corrected. arXiv admin note: text overlap with arXiv:2307.00286

Published
2023

12. Artificial intelligence to advance Earth observation: : A review of models, recent trends, and pathways forward

Author

Tuia, Devis, Schindler, Konrad, Demir, Begüm, Zhu, Xiao Xiang, Kochupillai, Mrinalini, Džeroski, Sašo, van Rijn, Jan N., Hoos, Holger H., Del Frate, Fabio, Datcu, Mihai, Markl, Volker, Saux, Bertrand Le, Schneider, Rochelle, and Camps-Valls, Gustau

Subjects
Computer Science - Computer Vision and Pattern Recognition, Electrical Engineering and Systems Science - Image and Video Processing, Statistics - Applications
Abstract

Earth observation (EO) is a prime instrument for monitoring land and ocean processes, studying the dynamics at work, and taking the pulse of our planet. This article gives a bird's eye view of the essential scientific tools and approaches informing and supporting the transition from raw EO data to usable EO-based information. The promises, as well as the current challenges of these developments, are highlighted under dedicated sections. Specifically, we cover the impact of (i) Computer vision; (ii) Machine learning; (iii) Advanced processing and computing; (iv) Knowledge-based AI; (v) Explainable AI and causal inference; (vi) Physics-aware models; (vii) User-centric approaches; and (viii) the much-needed discussion of ethical and societal issues related to the massive use of ML technologies in EO.

Published
2023
Full Text
View/download PDF

13. Greater male variability in daily energy expenditure develops through puberty.

Author

Haisma, Hinke, Hambly, Catherine, Hoffman, Daniel, Hoos, Marije, Hu, Sumei, Joonas, Noorjehan, Joosen, Annemiek, Katzmarzyk, Peter, Kempen, Kitty, Kimura, Misaka, Kraus, William, Kriengsinyos, Wantanee, Kuriyan, Rebecca, Kushner, Robert, Lambert, Estelle, Lanerolle, Pulani, Larsson, Christel, Lessan, Nader, Löf, Marie, Martin, Corby, Matsiko, Eric, Meijer, Gerwin, Morehen, James, Morton, James, Must, Aviva, Neuheuser, Marian, Nicklas, Theresa, Ojiambo, Robert, Pietilainen, Kirsi, Pitsiladis, Yannis, Plange-Rhule, Jacob, Plasqui, Guy, Prentice, Ross, Rabinovich, Roberto, Racette, Susan, Raichen, David, Ravussin, Eric, Redman, Leanne, Reilly, John, Reynolds, Rebecca, Roberts, Susan, Rood, Jennifer, Samaranayake, Dulani, Sardinha, Luís, Scuitt, Albertine, Silva, Analiza, Sinha, Srishti, Sjödin, Anders, Stice, Eric, Stunkard, Albert, Urlacher, Samuel, Valencia, Mauro, Valenti, Giulio, van Etten, Ludo, Van Mil, Edgar, Verbunt, Jeanine, Wells, Jonathan, Wilson, George, Wood, Brian, Yoshida, Tsukasa, Zhang, Xueying, Murphy-Alford, Alexia, Loechl, Cornelia, Luke, Amy, Pontzer, Herman, Sagayama, Hiroyuki, Westerterp, Klaas, Wong, William, Yamada, Yosuke, Speakman, John, Halsey, Lewis, Careau, Vincent, Ainslie, Philip, Alemán-Mateo, Heliodoro, Andersen, Lene, Anderson, Liam, Arab, Leonore, Baddou, Issad, Bandini, Linda, Bedu-Addo, Kweku, Blaak, Ellen, Blanc, Stephane, Bonomi, Alberto, Bouten, Carlijn, Bovet, Pascal, Brage, Soren, Buchowski, Maciej, Butte, Nancy, Camps, Stephan, Casper, Regian, Close, Graeme, Colbert, Lisa, Cooper, Jamie, Cooper, Richard, Dabare, Prasangi, Das, Sai, Davies, Peter, Deb, Sanjoy, and Nyström, Christine

Subjects
age, height, inter-individual variation, morphometry, weight, Adolescent, Young Adult, Female, Humans, Male, Adult, Puberty, Sexual Behavior, Reproduction, Energy Metabolism, Phenotype
Abstract

There is considerably greater variation in metabolic rates between men than between women, in terms of basal, activity and total (daily) energy expenditure (EE). One possible explanation is that EE is associated with male sexual characteristics (which are known to vary more than other traits) such as musculature and athletic capacity. Such traits might be predicted to be most prominent during periods of adolescence and young adulthood, when sexual behaviour develops and peaks. We tested this hypothesis on a large dataset by comparing the amount of male variation and female variation in total EE, activity EE and basal EE, at different life stages, along with several morphological traits: height, fat free mass and fat mass. Total EE, and to some degree also activity EE, exhibit considerable greater male variation (GMV) in young adults, and then a decreasing GMV in progressively older individuals. Arguably, basal EE, and also morphometrics, do not exhibit this pattern. These findings suggest that single male sexual characteristics may not exhibit peak GMV in young adulthood, however total and perhaps also activity EE, associated with many morphological and physiological traits combined, do exhibit GMV most prominently during the reproductive life stages.

Published
2023

22. A Preliminary Study to Examining Per-class Performance Bias via Robustness Distributions

Author

Bosman, Annelot W., Münz, Anna L., Hoos, Holger H., van Rijn, Jan N., Goos, Gerhard, Series Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Avni, Guy, editor, Giacobbe, Mirco, editor, Johnson, Taylor T., editor, Katz, Guy, editor, Lukina, Anna, editor, Narodytska, Nina, editor, and Schilling, Christian, editor

Published
2024
Full Text
View/download PDF

23. Implementation Patterns for Zone Architectures in Enterprise-Grade Data Lakes

Author

Giebler, Corinna, Gröger, Christoph, Hoos, Eva, Schwarz, Holger, Mitschang, Bernhard, Goos, Gerhard, Series Editor, Hartmanis, Juris, Founding Editor, van Leeuwen, Jan, Series Editor, Hutchison, David, Editorial Board Member, Kanade, Takeo, Editorial Board Member, Kittler, Josef, Editorial Board Member, Kleinberg, Jon M., Editorial Board Member, Kobsa, Alfred, Series Editor, Mattern, Friedemann, Editorial Board Member, Mitchell, John C., Editorial Board Member, Naor, Moni, Editorial Board Member, Nierstrasz, Oscar, Series Editor, Pandu Rangan, C., Editorial Board Member, Sudan, Madhu, Series Editor, Terzopoulos, Demetri, Editorial Board Member, Tygar, Doug, Editorial Board Member, Weikum, Gerhard, Series Editor, Vardi, Moshe Y, Series Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Woeginger, Gerhard, Editorial Board Member, Guizzardi, Giancarlo, editor, Santoro, Flavia, editor, Mouratidis, Haralambos, editor, and Soffer, Pnina, editor

Published
2024
Full Text
View/download PDF

24. Automated Configuration and Usage of Strategy Portfolios for Bargaining

Author

Renting, Bram M., Hoos, Holger H., and Jonker, Catholijn M.

Subjects
Computer Science - Multiagent Systems
Abstract

Bargaining can be used to resolve mixed-motive games in multi-agent systems. Although there is an abundance of negotiation strategies implemented in automated negotiating agents, most agents are based on single fixed strategies, while it is widely acknowledged that there is no single best-performing strategy for all negotiation settings. In this paper, we focus on bargaining settings where opponents are repeatedly encountered, but the bargaining problems change. We introduce a novel method that automatically creates and deploys a portfolio of complementary negotiation strategies using a training set and optimise pay-off in never-before-seen bargaining settings through per-setting strategy selection. Our method relies on the following contributions. We introduce a feature representation that captures characteristics for both the opponent and the bargaining problem. We model the behaviour of an opponent during a negotiation based on its actions, which is indicative of its negotiation strategy, in order to be more effective in future encounters. Our combination of feature-based methods generalises to new negotiation settings, as in practice, over time, it selects effective counter strategies in future encounters. Our approach is tested in an ANAC-like tournament, and we show that we are capable of winning such a tournament with a 5.6% increase in pay-off compared to the runner-up agent., Comment: Accepted to the Cooperative AI workshop @ NeurIPS 2021 (non-archival). Extended version accepted to AAMAS 2022: https://ifaamas.org/Proceedings/aamas2022/pdfs/p1101.pdf

Published
2022

25. The association between maximal muscle strength, disease severity and psychopharmacotherapy among young to middle-aged inpatients with affective disorders – a prospective pilot study

Author

Hannah Ramming, Linda Theuerkauf, Olaf Hoos, Katharina Lichter, and Sarah Kittel-Schneider

Subjects
Affective disorder, Depression, Bipolar disorder, Muscle strength, Psychopharmacotherapy, Young, Psychiatry, RC435-571
Abstract

Abstract Background Motor alterations and lowered physical activity are common in affective disorders. Previous research has indicated a link between depressive symptoms and declining muscle strength primarily focusing on the elderly but not younger individuals. Thus, we aimed to evaluate the relationship between mood and muscle strength in a sample of N = 73 young to middle-aged hospitalized patients (18–49 years, mean age 30.7 years) diagnosed with major depressive, bipolar and schizoaffective disorder, with a focus on moderating effects of psychopharmacotherapy. The study was carried out as a prospective observational study at a German psychiatric university hospital between September 2021 and March 2022. Methods Employing a standardized strength circuit consisting of computerized strength training devices, we measured the maximal muscle strength (Fmax) using three repetitions maximum across four muscle regions (abdomen, arm, back, leg) at three time points (t1-t3) over four weeks accompanied by psychometric testing (MADRS, BPRS, YRMS) and blood lipid profiling in a clinical setting. For analysis of psychopharmacotherapy, medication was split into activating (AM) and inhibiting (IM) medication and dosages were normalized by the respective WHO defined daily dose. Results While we observed a significant decrease of the MADRS score and increase of the relative total Fmax (rTFmax) in the first two weeks (t1-t2) but not later (both p

Published
2024
Full Text
View/download PDF

27. Impact of isotype on the mechanism of action of agonist anti-OX40 antibodies in cancer: implications for therapeutic combinations

Author

Junping Jing, Laura Bover, C Ian Mockridge, Kerry L Cox, Mark S Cragg, Tatyana Inzhelevskaya, Chris A Penfold, Vikki English, Jane E Willoughby, Hong Shi, Peter J Morley, Heather Jackson, Roopa Srinivasan, Tom Murray, Axel Hoos, Paul Bojczuk, James Smothers, Niranjan Yanamandra, Lang Dou, Sabyasachi Bhattacharya, Laura Seestaller-Wehr, David Kilian, Kui S Voo, Mel John, Heather Niederer, Andrew J Shepherd, Laura Hook, Stephanie Hopley, Sara J Brett, Christopher Hopson, Elaine Paul, and Stephen L Martin

Subjects
Neoplasms. Tumors. Oncology. Including cancer and carcinogens, RC254-282
Abstract

Background OX40 has been widely studied as a target for immunotherapy with agonist antibodies taken forward into clinical trials for cancer where they are yet to show substantial efficacy. Here, we investigated potential mechanisms of action of anti-mouse (m) OX40 and anti-human (h) OX40 antibodies, including a clinically relevant monoclonal antibody (mAb) (GSK3174998) and evaluated how isotype can alter those mechanisms with the aim to develop improved antibodies for use in rational combination treatments for cancer.Methods Anti-mOX40 and anti-hOX40 mAbs were evaluated in a number of in vivo models, including an OT-I adoptive transfer immunization model in hOX40 knock-in (KI) mice and syngeneic tumor models. The impact of FcγR engagement was evaluated in hOX40 KI mice deficient for Fc gamma receptors (FcγR). Additionally, combination studies using anti-mouse programmed cell death protein-1 (mPD-1) were assessed. In vitro experiments using peripheral blood mononuclear cells (PBMCs) examining possible anti-hOX40 mAb mechanisms of action were also performed.Results Isotype variants of the clinically relevant mAb GSK3174998 showed immunomodulatory effects that differed in mechanism; mIgG1 mediated direct T-cell agonism while mIgG2a acted indirectly, likely through depletion of regulatory T cells (Tregs) via activating FcγRs. In both the OT-I and EG.7-OVA models, hIgG1 was the most effective human isotype, capable of acting both directly and through Treg depletion. The anti-hOX40 hIgG1 synergized with anti-mPD-1 to improve therapeutic outcomes in the EG.7-OVA model. Finally, in vitro assays with human peripheral blood mononuclear cells (hPBMCs), anti-hOX40 hIgG1 also showed the potential for T-cell stimulation and Treg depletion.Conclusions These findings underline the importance of understanding the role of isotype in the mechanism of action of therapeutic mAbs. As an hIgG1, the anti-hOX40 mAb can elicit multiple mechanisms of action that could aid or hinder therapeutic outcomes, dependent on the microenvironment. This should be considered when designing potential combinatorial partners and their FcγR requirements to achieve maximal benefit and improvement of patient outcomes.

Published
2024
Full Text
View/download PDF

29. Measuring Inclusive Instruction at German Universities: Extending Validity Evidence

Author

Lombardi, Allison, Buenner, Laura, Loose, Julia, and Hoos, Olaf

Abstract

Promoting the use of inclusive instruction based on the tenets of Universal Design has occurred in the United States over the past three decades. In this study, a validated measure of university faculty attitudes toward inclusive instruction was translated from English to German and administered to a sample of faculty at a German institution. Responses (n=589) were subjected to an exploratory and confirmatory factor analysis in order to validate the translated items. The exploratory factor analysis yielded seven factors, which were very similar to the English version of the measure. The confirmatory factor analysis indicated the seven-factor solution showed acceptable model fit. Implications are discussed for universities both in the United States and abroad.

Published
2021

30. Variation in human water turnover associated with environmental and lifestyle factors

Author

Yamada, Yosuke, Zhang, Xueying, Henderson, Mary ET, Sagayama, Hiroyuki, Pontzer, Herman, Watanabe, Daiki, Yoshida, Tsukasa, Kimura, Misaka, Ainslie, Philip N, Andersen, Lene F, Anderson, Liam J, Arab, Lenore, Baddou, Issad, Bedu-Addo, Kweku, Blaak, Ellen E, Blanc, Stephane, Bonomi, Alberto G, Bouten, Carlijn VC, Bovet, Pascal, Buchowski, Maciej S, Butte, Nancy F, Camps, Stefan G, Close, Graeme L, Cooper, Jamie A, Cooper, Richard, Das, Sai Krupa, Dugas, Lara R, Eaton, Simon, Ekelund, Ulf, Entringer, Sonja, Forrester, Terrence, Fudge, Barry W, Goris, Annelies H, Gurven, Michael, Halsey, Lewis G, Hambly, Catherine, Hamdouchi, Asmaa El, Hoos, Marije B, Hu, Sumei, Joonas, Noorjehan, Joosen, Annemiek M, Katzmarzyk, Peter, Kempen, Kitty P, Kraus, William E, Kriengsinyos, Wantanee, Kushner, Robert F, Lambert, Estelle V, Leonard, William R, Lessan, Nader, Martin, Corby K, Medin, Anine C, Meijer, Erwin P, Morehen, James C, Morton, James P, Neuhouser, Marian L, Nicklas, Theresa A, Ojiambo, Robert M, Pietiläinen, Kirsi H, Pitsiladis, Yannis P, Plange-Rhule, Jacob, Plasqui, Guy, Prentice, Ross L, Rabinovich, Roberto A, Racette, Susan B, Raichlen, David A, Ravussin, Eric, Redman, Leanne M, Reilly, John J, Reynolds, Rebecca M, Roberts, Susan B, Schuit, Albertine J, Sardinha, Luis B, Silva, Analiza M, Sjödin, Anders M, Stice, Eric, Urlacher, Samuel S, Valenti, Giulio, Van Etten, Ludo M, Van Mil, Edgar A, Wells, Jonathan CK, Wilson, George, Wood, Brian M, Yanovski, Jack A, Murphy-Alford, Alexia J, Loechl, Cornelia U, Luke, Amy H, Rood, Jennifer, Westerterp, Klaas R, Wong, William W, Miyachi, Motohiko, Schoeller, Dale A, Speakman, John R, and Consortium§, International Atomic Energy Agency Doubly Labeled Water Database

Subjects
Prevention, Clean Water and Sanitation, Female, Humans, Pregnancy, Exercise, Humidity, Life Style, Social Class, Water, Infant, Newborn, Infant, Child, Preschool, Child, Adolescent, Young Adult, Adult, Middle Aged, Aged, Aged, 80 and over, Drinking, International Atomic Energy Agency (IAEA) Doubly Labeled Water (DLW) Database Consortium§, General Science & Technology
Abstract

Water is essential for survival, but one in three individuals worldwide (2.2 billion people) lacks access to safe drinking water. Water intake requirements largely reflect water turnover (WT), the water used by the body each day. We investigated the determinants of human WT in 5604 people from the ages of 8 days to 96 years from 23 countries using isotope-tracking (2H) methods. Age, body size, and composition were significantly associated with WT, as were physical activity, athletic status, pregnancy, socioeconomic status, and environmental characteristics (latitude, altitude, air temperature, and humidity). People who lived in countries with a low human development index (HDI) had higher WT than people in high-HDI countries. On the basis of this extensive dataset, we provide equations to predict human WT in relation to anthropometric, economic, and environmental factors.

Published
2022

31. Variability in energy expenditure is much greater in males than females

Author

Halsey, Lewis G, Careau, Vincent, Pontzer, Herman, Ainslie, Philip N, Andersen, Lene F, Anderson, Liam J, Arab, Lenore, Baddou, Issad, Bedu-Addo, Kweku, Blaak, Ellen E, Blanc, Stephane, Bonomi, Alberto G, Bouten, Carlijn VC, Bovet, Pascal, Buchowski, Maciej S, Butte, Nancy F, Camps, Stefan GJA, Close, Graeme L, Cooper, Jamie A, Das, Sai Krupa, Cooper, Richard, Dugas, Lara R, Ekelund, Ulf, Entringer, Sonja, Forrester, Terrence, Fudge, Barry W, Goris, Annelies H, Gurven, Michael, Hambly, Catherine, Hamdouchi, Asmaa El, Hoos, Marije B, Hu, Sumei, Joonas, Noorjehan, Joosen, Annemiek M, Katzmarzyk, Peter, Kempen, Kitty P, Kimura, Misaka, Kraus, William E, Kushner, Robert F, Lambert, Estelle V, Leonard, William R, Lessan, Nader, Martin, Corby K, Medin, Anine C, Meijer, Erwin P, Morehen, James C, Morton, James P, Neuhouser, Marian L, Nicklas, Theresa A, Ojiambo, Robert M, Pietiläinen, Kirsi H, Pitsiladis, Yannis P, Plange-Rhule, Jacob, Plasqui, Guy, Prentice, Ross L, Rabinovich, Roberto A, Racette, Susan B, Raichlen, David A, Ravussin, Eric, Reynolds, Rebecca M, Roberts, Susan B, Schuit, Albertine J, Sjödin, Anders M, Stice, Eric, Urlacher, Samuel S, Valenti, Giulio, Van Etten, Ludo M, Van Mil, Edgar A, Wilson, George, Wood, Brian M, Yanovski, Jack, Yoshida, Tsukasa, Zhang, Xueying, Murphy-Alford, Alexia J, Loechl, Cornelia U, Luke, Amy H, Rood, Jennifer, Sagayama, Hiroyuki, Schoeller, Dale A, Westerterp, Klaas R, Wong, William W, Yamada, Yosuke, and Speakman, John R

Subjects
Obesity, Behavioral and Social Science, Affordable and Clean Energy, Adult, Aged, Aging, Animals, Body Composition, Energy Metabolism, Female, Humans, Male, Mammals, Reproduction, Sex Characteristics, DLW, Energetics, Activity, Trait variability, Biological sex, Evolutionary Biology, Anthropology, Archaeology
Abstract

In mammals, trait variation is often reported to be greater among males than females. However, to date, mainly only morphological traits have been studied. Energy expenditure represents the metabolic costs of multiple physical, physiological, and behavioral traits. Energy expenditure could exhibit particularly high greater male variation through a cumulative effect if those traits mostly exhibit greater male variation, or a lack of greater male variation if many of them do not. Sex differences in energy expenditure variation have been little explored. We analyzed a large database on energy expenditure in adult humans (1494 males and 3108 females) to investigate whether humans have evolved sex differences in the degree of interindividual variation in energy expenditure. We found that, even when statistically comparing males and females of the same age, height, and body composition, there is much more variation in total, activity, and basal energy expenditure among males. However, with aging, variation in total energy expenditure decreases, and because this happens more rapidly in males, the magnitude of greater male variation, though still large, is attenuated in older age groups. Considerably greater male variation in both total and activity energy expenditure could be explained by greater male variation in levels of daily activity. The considerably greater male variation in basal energy expenditure is remarkable and may be explained, at least in part, by greater male variation in the size of energy-demanding organs. If energy expenditure is a trait that is of indirect interest to females when choosing a sexual partner, this would suggest that energy expenditure is under sexual selection. However, we present a novel energetics model demonstrating that it is also possible that females have been under stabilizing selection pressure for an intermediate basal energy expenditure to maximize energy available for reproduction.

Published
2022

33. Risk Factors for Enteric Pathogen Exposure among Children in Black Belt Region of Alabama, USA

Author

Capone, Drew, Bakare, Toheedat, Barker, Troy, Chatham, Amy Hutson, Clark, Ryan, Copperthwaite, Lauren, Flemister, Abeoseh, Geason, Riley, Hoos, Emery, Kim, Elizabeth, Manoj, Alka, Pomper, Sam, Samodal, Christina, Smith, Simrill, Poole, Claudette, and Brown, Joe

Subjects
Medical research, Medicine, Experimental, Water -- Management, Escherichia coli -- Genetic aspects, Health
Abstract

Outside cities and towns served by conventional sewerage, many residents in the rural Black Belt region of Alabama, USA, have failing or inadequate sanitation infrastructure (1,2). This region was named [...]

Published
2023
Full Text
View/download PDF

34. Antigen self-anchoring onto bacteriophage T5 capsid-like particles for vaccine design

Author

Emeline Vernhes, Linda Larbi Chérif, Nicolas Ducrot, Clément Vanbergue, Malika Ouldali, Lena Zig, N’diaye Sidibe, Sylviane Hoos, Luis Ramirez-Chamorro, Madalena Renouard, Ombeline Rossier, Patrick England, Guy Schoehn, Pascale Boulanger, and Karim Benihoud

Subjects
Immunologic diseases. Allergy, RC581-607, Neoplasms. Tumors. Oncology. Including cancer and carcinogens, RC254-282
Abstract

Abstract The promises of vaccines based on virus-like particles stimulate demand for universal non-infectious virus-like platforms that can be efficiently grafted with large antigens. Here, we harnessed the modularity and extreme affinity of the decoration protein pb10 for the capsid of bacteriophage T5. SPR experiments demonstrated that pb10 fused to mCherry or to the model antigen ovalbumin (Ova) retained picomolar affinity for DNA-free T5 capsid-like particles (T5-CLPs), while cryo-EM studies attested to the full occupancy of the 120 capsid binding sites. Mice immunization with CLP-bound pb10-Ova chimeras elicited strong long-lasting anti-Ova humoral responses involving a large panel of isotypes, as well as CD8+ T cell responses, without any extrinsic adjuvant. Therefore, T5-CLP constitutes a unique DNA-free bacteriophage capsid able to display a regular array of large antigens through highly efficient chemical-free anchoring. Its ability to elicit robust immune responses paves the way for further development of this novel vaccination platform.

Published
2024
Full Text
View/download PDF

35. Human total, basal and activity energy expenditures are independent of ambient environmental temperature

Author

Zhang, Xueying, Yamada, Yosuke, Sagayama, Hiroyuki, Ainslie, Philip N, Blaak, Ellen E, Buchowski, Maciej S, Close, Graeme L, Cooper, Jamie A, Das, Sai Krupa, Dugas, Lara R, Gurven, Michael, Hamdouchi, Asmaa El, Hu, Sumei, Joonas, Noorjehan, Katzmarzyk, Peter, Kraus, William E, Kushner, Robert F, Leonard, William R, Martin, Corby K, Meijer, Erwin P, Neuhouser, Marian L, Ojiambo, Robert M, Pitsiladis, Yannis P, Plasqui, Guy, Prentice, Ross L, Racette, Susan B, Ravussin, Eric, Redman, Leanne M, Reynolds, Rebecca M, Roberts, Susan B, Sardinha, Luis B, Silva, Analiza M, Stice, Eric, Urlacher, Samuel S, Van Mil, Edgar A, Wood, Brian M, Murphy-Alford, Alexia J, Loechl, Cornelia, Luke, Amy H, Rood, Jennifer, Schoeller, Dale A, Westerterp, Klaas R, Wong, William W, Pontzer, Herman, Speakman, John R, consortium, the IAEA DLW database, Andersen, Lene F, Anderson, Liam J, Arab, Lenore, Baddou, Issad, Addo, Bedu, Blanc, Stephane, Bonomi, Alberto, Bouten, Carlijn VC, Bovet, Pascal, Branth, Stefan, De Bruin, Niels C, Butte, Nancy F, Colbert, Lisa H, Camps, Stephan G, Dutman, Alice E, Eaton, Simon D, Ekelund, Ulf, Entringer, Sonja, Ebbeling, Cara, Elmståhl, Sölve, Fogelholm, Mikael, Forrester, Terrence, Fudge, Barry W, Harris, Tamara, Heijligenberg, Rik, Goris, Annelies H, Hambly, Catherine, Hoos, Marije B, Jorgensen, Hans U, Joosen, Annemiek M, Kempen, Kitty P, Kimura, Misaka, Kriengsinyos, Watanee, Lambert, Estelle V, Larsson, Christel L, Lessan, Nader, Ludwig, David S, McCloskey, Margaret, Medin, Anine C, Meijer, Gerwin A, Matsiko, Eric, Melse-Boonstra, Alida, Morehen, James C, Morton, James P, Nicklas, Theresa A, Pannemans, Daphne L, Pietiläinen, Kirsi H, Philippaerts, Renaat M, Rabinovich, Roberto A, Reilly, John J, Rothenberg, Elisabet M, Schuit, Albertine J, Schulz, Sabine, and Sjödin, Anders M

Subjects
Nutrition, IAEA DLW database consortium, Human Physiology, Human activity in medical context, Human metabolism
Abstract

Lower ambient temperature (Ta) requires greater energy expenditure to sustain body temperature. However, effects of Ta on human energetics may be buffered by environmental modification and behavioral compensation. We used the IAEA DLW database for adults in the USA (n = 3213) to determine the effect of Ta (-10 to +30°C) on TEE, basal (BEE) and activity energy expenditure (AEE) and physical activity level (PAL). There were no significant relationships (p > 0.05) between maximum, minimum and average Ta and TEE, BEE, AEE and PAL. After adjustment for fat-free mass, fat mass and age, statistically significant (p

Published
2022

36. Frugal Machine Learning

Author

Evchenko, Mikhail, Vanschoren, Joaquin, Hoos, Holger H., Schoenauer, Marc, and Sebag, Michèle

Subjects
Computer Science - Machine Learning, Electrical Engineering and Systems Science - Signal Processing
Abstract

Machine learning, already at the core of increasingly many systems and applications, is set to become even more ubiquitous with the rapid rise of wearable devices and the Internet of Things. In most machine learning applications, the main focus is on the quality of the results achieved (e.g., prediction accuracy), and hence vast amounts of data are being collected, requiring significant computational resources to build models. In many scenarios, however, it is infeasible or impractical to set up large centralized data repositories. In personal health, for instance, privacy issues may inhibit the sharing of detailed personal data. In such cases, machine learning should ideally be performed on wearable devices themselves, which raises major computational limitations such as the battery capacity of smartwatches. This paper thus investigates frugal learning, aimed to build the most accurate possible models using the least amount of resources. A wide range of learning algorithms is examined through a frugal lens, analyzing their accuracy/runtime performance on a wide range of data sets. The most promising algorithms are thereafter assessed in a real-world scenario by implementing them in a smartwatch and letting them learn activity recognition models on the watch itself.

Published
2021

37. Risk Factors for Enteric Pathogen Exposure among Children in Black Belt Region of Alabama, USA

Author

Drew Capone, Toheedat Bakare, Troy Barker, Amy Hutson Chatham, Ryan Clark, Lauren Copperthwaite, Abeoseh Flemister, Riley Geason, Emery Hoos, Elizabeth Kim, Alka Manoj, Sam Pomper, Christina Samodal, Simrill Smith, Claudette Poole, and Joe Brown

Subjects
enteric infections, Black Belt, enteric pathogens, well water, straight pipe, sanitation, Medicine, Infectious and parasitic diseases, RC109-216
Abstract

We collected stool from school-age children from 352 households living in the Black Belt region of Alabama, USA, where sanitation infrastructure is lacking. We used quantitative reverse transcription PCR to measure key pathogens in stool that may be associated with water and sanitation, as an indicator of exposure. We detected genes associated with >1 targets in 26% of specimens, most frequently Clostridioides difficile (6.6%), atypical enteropathogenic Escherichia coli (6.1%), and enteroaggregative E. coli (3.9%). We used generalized estimating equations to assess reported risk factors for detecting >1 pathogen in stool. We found no association between lack of sanitation and pathogen detection (adjusted risk ratio 0.95 [95% CI 0.55–1.7]) compared with specimens from children served by sewerage. However, we did observe an increased risk for pathogen detection among children living in homes with well water (adjusted risk ratio 1.7 [95% CI 1.1–2.5]) over those reporting water utility service.

Published
2023
Full Text
View/download PDF

38. Introducing the enterprise data marketplace: a platform for democratizing company data

Author

Rebecca Eichler, Christoph Gröger, Eva Hoos, Christoph Stach, Holger Schwarz, and Bernhard Mitschang

Subjects
Data Catalog, Data Democratization, Data Market, Data Sharing, Enterprise Data Marketplace, Metadata Management, Computer engineering. Computer hardware, TK7885-7895, Information technology, T58.5-58.64, Electronic computers. Computer science, QA75.5-76.95
Abstract

Abstract In this big data era, multitudes of data are generated and collected which contain the potential to gain new insights, e.g., for enhancing business models. To leverage this potential through, e.g., data science and analytics projects, the data must be made available. In this context, data marketplaces are used as platforms to facilitate the exchange and thus, the provisioning of data and data-related services. Data marketplaces are mainly studied for the exchange of data between organizations, i.e., as external data marketplaces. Yet, the data collected within a company also has the potential to provide valuable insights for this same company, for instance to optimize business processes. Studies indicate, however, that a significant amount of data within companies remains unused. In this sense, it is proposed to employ an Enterprise Data Marketplace, a platform to democratize data within a company among its employees. Specifics of the Enterprise Data Marketplace, how it can be implemented or how it makes data available throughout a variety of systems like data lakes has not been investigated in literature so far. Therefore, we present the characteristics and requirements of this kind of marketplace. We also distinguish it from other tools like data catalogs, provide a platform architecture and highlight how it integrates with the company’s system landscape. The presented concepts are demonstrated through an Enterprise Data Marketplace prototype and an experiment reveals that this marketplace significantly improves the data consumer workflows in terms of efficiency and complexity. This paper is based on several interdisciplinary works combining comprehensive research with practical experience from an industrial perspective. We therefore present the Enterprise Data Marketplace as a distinct marketplace type and provide the basis for establishing it within a company.

Published
2023
Full Text
View/download PDF

40. Total energy expenditure is repeatable in adults but not associated with short-term changes in body composition

Author

Rimbach, Rebecca, Yamada, Yosuke, Sagayama, Hiroyuki, Ainslie, Philip N, Anderson, Lene F, Anderson, Liam J, Arab, Lenore, Baddou, Issaad, Bedu-Addo, Kweku, Blaak, Ellen E, Blanc, Stephane, Bonomi, Alberto G, Bouten, Carlijn VC, Bovet, Pascal, Buchowski, Maciej S, Butte, Nancy F, Camps, Stefan GJA, Close, Graeme L, Cooper, Jamie A, Das, Sai Krupa, Dugas, Lara R, Ekelund, Ulf, Entringer, Sonja, Forrester, Terrence, Fudge, Barry W, Goris, Annelies H, Gurven, Michael, Hambly, Catherine, El Hamdouchi, Asmaa, Hoos, Marije B, Hu, Sumei, Joonas, Noorjehan, Joosen, Annemiek M, Katzmarzyk, Peter, Kempen, Kitty P, Kimura, Misaka, Kraus, William E, Kushner, Robert F, Lambert, Estelle V, Leonard, William R, Lessan, Nader, Martin, Corby K, Medin, Anine C, Meijer, Erwin P, Morehen, James C, Morton, James P, Neuhouser, Marian L, Nicklas, Theresa A, Ojiambo, Robert M, Pietiläinen, Kirsi H, Pitsiladis, Yannis P, Plange-Rhule, Jacob, Plasqui, Guy, Prentice, Ross L, Rabinovich, Roberto A, Racette, Susan B, Raichlen, David A, Ravussin, Eric, Reynolds, Rebecca M, Roberts, Susan B, Schuit, Albertine J, Sjödin, Anders M, Stice, Eric, Urlacher, Samuel S, Valenti, Giulio, Van Etten, Ludo M, Van Mil, Edgar A, Wells, Jonathan CK, Wilson, George, Wood, Brian M, Yanovski, Jack, Yoshida, Tsukasa, Zhang, Xueying, Murphy-Alford, Alexia J, Loechl, Cornelia U, Luke, Amy H, Rood, Jennifer, Schoeller, Dale A, Westerterp, Klaas R, Wong, William W, Speakman, John R, and Pontzer, Herman

Subjects
Nutrition, Pediatric, Clinical Research, Obesity, Aetiology, 2.1 Biological and endogenous factors, Metabolic and endocrine, Adipose Tissue, Adult, Bayes Theorem, Body Composition, Child, Databases, Factual, Energy Metabolism, Female, Humans, Isotope Labeling, Longitudinal Studies, Male, Middle Aged, Water, Weight Gain, IAEA DLW Database Consortium
Abstract

Low total energy expenditure (TEE, MJ/d) has been a hypothesized risk factor for weight gain, but repeatability of TEE, a critical variable in longitudinal studies of energy balance, is understudied. We examine repeated doubly labeled water (DLW) measurements of TEE in 348 adults and 47 children from the IAEA DLW Database (mean ± SD time interval: 1.9 ± 2.9 y) to assess repeatability of TEE, and to examine if TEE adjusted for age, sex, fat-free mass, and fat mass is associated with changes in weight or body composition. Here, we report that repeatability of TEE is high for adults, but not children. Bivariate Bayesian mixed models show no among or within-individual correlation between body composition (fat mass or percentage) and unadjusted TEE in adults. For adults aged 20-60 y (N = 267; time interval: 7.4 ± 12.2 weeks), increases in adjusted TEE are associated with weight gain but not with changes in body composition; results are similar for subjects with intervals >4 weeks (N = 53; 29.1 ± 12.8 weeks). This suggests low TEE is not a risk factor for, and high TEE is not protective against, weight or body fat gain over the time intervals tested.

Published
2022

41. Automating Data Science: Prospects and Challenges

Author

De Bie, Tijl, De Raedt, Luc, Hernández-Orallo, José, Hoos, Holger H., Smyth, Padhraic, and Williams, Christopher K. I.

Subjects
Computer Science - Databases, Computer Science - Machine Learning
Abstract

Given the complexity of typical data science projects and the associated demand for human expertise, automation has the potential to transform the data science process. Key insights: * Automation in data science aims to facilitate and transform the work of data scientists, not to replace them. * Important parts of data science are already being automated, especially in the modeling stages, where techniques such as automated machine learning (AutoML) are gaining traction. * Other aspects are harder to automate, not only because of technological challenges, but because open-ended and context-dependent tasks require human interaction., Comment: 19 pages, 3 figures. v1 accepted for publication (April 2021) in Communications of the ACM

Published
2021
Full Text
View/download PDF

42. Practices for Engineering Trustworthy Machine Learning Applications

Author

Serban, Alex, van der Blom, Koen, Hoos, Holger, and Visser, Joost

Subjects
Computer Science - Software Engineering
Abstract

Following the recent surge in adoption of machine learning (ML), the negative impact that improper use of ML can have on users and society is now also widely recognised. To address this issue, policy makers and other stakeholders, such as the European Commission or NIST, have proposed high-level guidelines aiming to promote trustworthy ML (i.e., lawful, ethical and robust). However, these guidelines do not specify actions to be taken by those involved in building ML systems. In this paper, we argue that guidelines related to the development of trustworthy ML can be translated to operational practices, and should become part of the ML development life cycle. Towards this goal, we ran a multi-vocal literature review, and mined operational practices from white and grey literature. Moreover, we launched a global survey to measure practice adoption and the effects of these practices. In total, we identified 14 new practices, and used them to complement an existing catalogue of ML engineering practices. Initial analysis of the survey results reveals that so far, practice adoption for trustworthy ML is relatively low. In particular, practices related to assuring security of ML components have very low adoption. Other practices enjoy slightly larger adoption, such as providing explanations to users. Our extended practice catalogue can be used by ML development teams to bridge the gap between high-level guidelines and actual development of trustworthy ML systems; it is open for review and contribution, Comment: Published at WAIN'21 - 1st Workshop on AI Engineering - Software Engineering for AI

Published
2021

46. Physical activity and fat-free mass during growth and in later life

Author

Westerterp, Klaas R, Yamada, Yosuke, Sagayama, Hiroyuki, Ainslie, Philip N, Andersen, Lene F, Anderson, Liam J, Arab, Lenore, Baddou, Issaad, Bedu-Addo, Kweku, Blaak, Ellen E, Blanc, Stephane, Bonomi, Alberto G, Bouten, Carlijn VC, Bovet, Pascal, Buchowski, Maciej S, Butte, Nancy F, Camps, Stefan GJA, Close, Graeme L, Cooper, Jamie A, Das, Sai K, Cooper, Richard, Dugas, Lara R, Ekelund, Ulf, Entringer, Sonja, Forrester, Terrence, Fudge, Barry W, Goris, Annelies H, Gurven, Michael, Hambly, Catherine, Hamdouchi, Asmaa El, Hoos, Marije B, Hu, Sumei, Joonas, Noorjehan, Joosen, Annemiek M, Katzmarzyk, Peter, Kempen, Kitty P, Kimura, Misaka, Kraus, William E, Kushner, Robert F, Lambert, Estelle V, Leonard, William R, Lessan, Nader, Martin, Corby K, Medin, Anine C, Meijer, Erwin P, Morehen, James C, Morton, James P, Neuhouser, Marian L, Nicklas, Theresa A, Ojiambo, Robert M, Pietiläinen, Kirsi H, Pitsiladis, Yannis P, Plange-Rhule, Jacob, Plasqui, Guy, Prentice, Ross L, Rabinovich, Roberto A, Racette, Susan B, Raichlen, David A, Ravussin, Eric, Reynolds, Rebecca M, Roberts, Susan B, Schuit, Albertine J, Sjödin, Anders M, Stice, Eric, Urlacher, Samuel S, Valenti, Giulio, Van Etten, Ludo M, Van Mil, Edgar A, Wells, Jonathan CK, Wilson, George, Wood, Brian M, Yanovski, Jack, Yoshida, Tsukasa, Zhang, Xueying, Murphy-Alford, Alexia J, Loechl, Cornelia U, Luke, Amy H, Pontzer, Herman, Rood, Jennifer, Schoeller, Dale A, Wong, William W, Speakman, John R, Branth, Stefan, Colbert, Lisa H, De Bruin, Niels C, Dutman, Alice E, Elmståhl, Sölve, Fogelholm, Mikael, Harris, Tamara, Heijligenberg, Rik, Jorgensen, Hans U, Larsson, Christel L, Rothenberg, Elisabet M, McCloskey, Margaret, Meijer, Gerwin A, Pannemans, Daphne L, Schulz, Sabine, Van den Berg-Emons, Rita, Van Gemert, Wim G, and Wilhelmine, W

Subjects
Prevention, Aging, Clinical Research, Nutrition, Adipose Tissue, Adolescent, Adult, Aged, Aged, 80 and over, Body Composition, Child, Child, Preschool, Cross-Sectional Studies, Energy Metabolism, Exercise, Female, Humans, Male, Middle Aged, Young Adult, physical activity level, age, energy expenditure, body composition, doubly labeled water, International Atomic Energy Agency Doubly Labeled Water database group, Engineering, Medical and Health Sciences, Nutrition & Dietetics
Abstract

BackgroundPhysical activity may be a way to increase and maintain fat-free mass (FFM) in later life, similar to the prevention of fractures by increasing peak bone mass.ObjectivesA study is presented of the association between FFM and physical activity in relation to age.MethodsIn a cross-sectional study, FFM was analyzed in relation to physical activity in a large participant group as compiled in the International Atomic Energy Agency Doubly Labeled Water database. The database included 2000 participants, age 3-96 y, with measurements of total energy expenditure (TEE) and resting energy expenditure (REE) to allow calculation of physical activity level (PAL = TEE/REE), and calculation of FFM from isotope dilution.ResultsPAL was a main determinant of body composition at all ages. Models with age, fat mass (FM), and PAL explained 76% and 85% of the variation in FFM in females and males

Published
2021

47. Energy compensation and adiposity in humans

Author

Careau, Vincent, Halsey, Lewis G, Pontzer, Herman, Ainslie, Philip N, Andersen, Lene F, Anderson, Liam J, Arab, Lenore, Baddou, Issad, Bedu-Addo, Kweku, Blaak, Ellen E, Blanc, Stephane, Bonomi, Alberto G, Bouten, Carlijn VC, Buchowski, Maciej S, Butte, Nancy F, Camps, Stefan GJA, Close, Graeme L, Cooper, Jamie A, Das, Sai Krupa, Cooper, Richard, Dugas, Lara R, Eaton, Simon D, Ekelund, Ulf, Entringer, Sonja, Forrester, Terrence, Fudge, Barry W, Goris, Annelies H, Gurven, Michael, Hambly, Catherine, Hamdouchi, Asmaa El, Hoos, Marije B, Hu, Sumei, Joonas, Noorjehan, Joosen, Annemiek M, Katzmarzyk, Peter, Kempen, Kitty P, Kimura, Misaka, Kraus, William E, Kushner, Robert F, Lambert, Estelle V, Leonard, William R, Lessan, Nader, Martin, Corby K, Medin, Anine C, Meijer, Erwin P, Morehen, James C, Morton, James P, Neuhouser, Marian L, Nicklas, Theresa A, Ojiambo, Robert M, Pietiläinen, Kirsi H, Pitsiladis, Yannis P, Plange-Rhule, Jacob, Plasqui, Guy, Prentice, Ross L, Rabinovich, Roberto A, Racette, Susan B, Raichlen, David A, Ravussin, Eric, Reilly, John J, Reynolds, Rebecca M, Roberts, Susan B, Schuit, Albertine J, Sjödin, Anders M, Stice, Eric, Urlacher, Samuel S, Valenti, Giulio, Van Etten, Ludo M, Van Mil, Edgar A, Wells, Jonathan CK, Wilson, George, Wood, Brian M, Yanovski, Jack, Yoshida, Tsukasa, Zhang, Xueying, Murphy-Alford, Alexia J, Loechl, Cornelia U, Luke, Amy H, Rood, Jennifer, Sagayama, Hiroyuki, Schoeller, Dale A, Wong, William W, Yamada, Yosuke, Speakman, John R, and group, the IAEA DLW database

Subjects
Nutrition, Obesity, Clinical Research, Oral and gastrointestinal, Stroke, Metabolic and endocrine, Cancer, Cardiovascular, Affordable and Clean Energy, Adiposity, Energy Intake, Energy Metabolism, Humans, IAEA DLW database group, Homo sapiens, activity, basal metabolic rate, daily energy expenditure, energy compensation, energy management models, exercise, trade-offs, weight loss, Biological Sciences, Medical and Health Sciences, Psychology and Cognitive Sciences, Developmental Biology
Abstract

Understanding the impacts of activity on energy balance is crucial. Increasing levels of activity may bring diminishing returns in energy expenditure because of compensatory responses in non-activity energy expenditures.1-3 This suggestion has profound implications for both the evolution of metabolism and human health. It implies that a long-term increase in activity does not directly translate into an increase in total energy expenditure (TEE) because other components of TEE may decrease in response-energy compensation. We used the largest dataset compiled on adult TEE and basal energy expenditure (BEE) (n = 1,754) of people living normal lives to find that energy compensation by a typical human averages 28% due to reduced BEE; this suggests that only 72% of the extra calories we burn from additional activity translates into extra calories burned that day. Moreover, the degree of energy compensation varied considerably between people of different body compositions. This association between compensation and adiposity could be due to among-individual differences in compensation: people who compensate more may be more likely to accumulate body fat. Alternatively, the process might occur within individuals: as we get fatter, our body might compensate more strongly for the calories burned during activity, making losing fat progressively more difficult. Determining the causality of the relationship between energy compensation and adiposity will be key to improving public health strategies regarding obesity.

Published
2021

49. Decline in Isotope Dilution Space Ratio Above Age 60 Could Affect Energy Estimates Using the Doubly Labeled Water Method

Author

Wong, William W, Speakman, John R, Ainslie, Philip N, Anderson, Liam J, Arab, Leonore, Baddou, Issad, Bedu-Addo, Kweku, Blaak, Ellen E, Blanc, Stephane, Bonomi, Alberto G, Bouten, Carlijn VC, Bovet, Pascal, Buchowski, Maciej S, Butte, Nancy F, Camps, Stefan G, Casper, Regina, Close, Graeme L, Colbert, Lisa H, Cooper, Jamie A, Das, Sai K, Davies, Peter SW, Eaton, Simon, Ekelund, Ulf, Hambly, Catherine, El Hamdouchi, Asmaa, Entringer, Sonja, Fudge, Barry W, Gillingham, Melanie, Goris, Annelies H, Gurven, Micheal, Hoos, Marije B, Hu, Sumei, Joosen, Annemiek, Katzmarzyk, Peter T, Kempen, Kitty P, Kimura, Misaka, Kraus, William E, Kushner, Robert F, Larsson, Christel L, Morehen, James C, Morton, James P, Neuhouser, Marian L, Nicklas, Theresa A, Ojiambo, Robert M, Pietilainen, Kirsi H, Pitsiladis, Yannis P, Plasqui, Guy, Prentice, Ross L, Rabinovich, Roberto, Racette, Susan B, Raichen, David A, Redman, Leanne, Ravussin, Eric, Reilly, John J, Roberts, Susan, Scuitt, Albertine J, Sjödin, Anders M, Stice, Eric, Urlacher, Samuel S, Valenti, Giulio, van Etten, Ludo M, Van Mil, Edgar A, Verbunt, Jeanine A, Wells, Jonathan CK, Wilson, George, Yoshida, Tsukasa, Zhang, Xueying, Loechl, Cornelia U, Luke, Amy, Murphy-Alford, Alexia J, Pontzer, Herman, Sagayama, Hiroyuki, Rood, Jennifer C, Schoeller, Dale A, Westerterp, Klaas R, and Yamada, Yosuke

Published
2024
Full Text
View/download PDF

50. Heart Rate Variability-Derived Thresholds for Exercise Intensity Prescription in Endurance Sports: A Systematic Review of Interrelations and Agreement with Different Ventilatory and Blood Lactate Thresholds

Author

Sebastian Kaufmann, Thomas Gronwald, Fabian Herold, and Olaf Hoos

Subjects
Exercise intensity, Intensity distribution, Vagal threshold, Endurance training, Performance testing, Sports medicine, RC1200-1245
Abstract

Abstract Background Exercise intensities are prescribed using specific intensity zones (moderate, heavy, and severe) determined by a ‘lower’ and a ‘higher’ threshold. Typically, ventilatory (VT) or blood lactate thresholds (LT), and critical power/speed concepts (CP/CS) are used. Various heart rate variability-derived thresholds (HRVTs) using different HRV indices may constitute applicable alternatives, but a systematic review of the proximity of HRVTs to established threshold concepts is lacking. Objective This systematic review aims to provide an overview of studies that determined HRVTs during endurance exercise in healthy adults in comparison with a reference VT and/or LT concept. Methods A systematic literature search for studies determining HRVTs in healthy individuals during endurance exercise and comparing them with VTs or LTs was conducted in Scopus, PubMed and Web of Science (until January 2022). Studies claiming to describe similar physiological boundaries to delineate moderate from heavy (HRVTlow vs. VTlow and/or LTlow), and heavy from severe intensity zone (HRVThigh vs. VThigh and/or LThigh) were grouped and their results synthesized. Results Twenty-seven included studies (461 participants) showed a mean difference in relative HR between HRVTlow and VTlow of − 0.6%bpm in weighted means and 0.02%bpm between HRVTlow and LTlow. Bias between HR at HRVTlow and VTlow was 1 bpm (limits of agreement (LoA): − 10.9 to 12.8 bpm) and 2.7 bpm (LoA: − 20.4 to 25.8 bpm) between HRVTlow and LTlow. Mean difference in HR between HRVThigh and VThigh was 0.3%bpm in weighted means and 2.9%bpm between HRVThigh and LThigh while bias between HR at HRVThigh and VThigh was − 4 bpm (LoA: − 17.9 to 9.9 bpm) and 2.5 bpm (LoA: − 12.1 to 17.1 bpm) between HRVThigh and LThigh. Conclusion HRVTlow seems to be a promising approach for the determination of a ‘lower’ threshold comparable to VTlow and potentially for HRVThigh compared to VThigh, although the latter needs further empirical evaluation. LoA for both intensity zone boundaries indicates bias of HRVTs on an individual level. Taken together, HRVTs can be a promising alternative for prescribing exercise intensity in healthy, male athletes undertaking endurance activities but due to the heterogeneity of study design, threshold concepts, standardization, and lack of female participants, further research is necessary to draw more robust and nuanced conclusions.

Published
2023
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results