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  1. Book ; Online: HOAX

    Thie, Albert / Menger, Maximilian F. S. J. / Faraji, Shirin

    A Hyperparameter Optimization Algorithm Explorer for Neural Networks

    2023  

    Abstract: Computational chemistry has become an important tool to predict and understand molecular properties and reactions. Even though recent years have seen a significant growth in new algorithms and computational methods that speed up quantum chemical ... ...

    Abstract Computational chemistry has become an important tool to predict and understand molecular properties and reactions. Even though recent years have seen a significant growth in new algorithms and computational methods that speed up quantum chemical calculations, the bottleneck for trajectory-based methods to study photoinduced processes is still the huge number of electronic structure calculations. In this work, we present an innovative solution, in which the amount of electronic structure calculations is drastically reduced, by employing machine learning algorithms and methods borrowed from the realm of artificial intelligence. However, applying these algorithms effectively requires finding optimal hyperparameters, which remains a challenge itself. Here we present an automated user-friendly framework, HOAX, to perform the hyperparameter optimization for neural networks, which bypasses the need for a lengthy manual process. The neural network generated potential energy surfaces (PESs) reduces the computational costs compared to the ab initio-based PESs. We perform a comparative investigation on the performance of different hyperparameter optimiziation algorithms, namely grid search, simulated annealing, genetic algorithm, and bayesian optimizer in finding the optimal hyperparameters necessary for constructing the well-performing neural network in order to fit the PESs of small organic molecules. Our results show that this automated toolkit not only facilitate a straightforward way to perform the hyperparameter optimization but also the resulting neural networks-based generated PESs are in reasonable agreement with the ab initio-based PESs.

    Comment: 18 pages
    Keywords Physics - Chemical Physics ; Computer Science - Machine Learning
    Subject code 006
    Publishing date 2023-02-01
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Book ; Online: Fiscally Informed Total Force Manpower

    Thie, Harry J / Christian, John / Stafford, Matthew / Yardley, Roland J / Schirmer, Peter

    2008  

    Keywords Personnel & human resources management ; Political control & freedoms ; Political Science ; Management & Organizational Behavior
    Language English
    Size 1 Online-Ressource
    Publisher RAND Corporation
    Document type Book ; Online
    Note English
    HBZ-ID HT030609397
    ISBN 9780833044181 ; 0833044184
    Database ZB MED Catalogue: Medicine, Health, Nutrition, Environment, Agriculture

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  3. Article: A mathematical approach to reaction mechanisms.

    THIE, J

    The Journal of physical and colloid chemistry

    2010  Volume 51, Issue 2, Page(s) 540–556

    MeSH term(s) Chemistry ; Mathematics
    Language English
    Publishing date 2010-02-04
    Publishing country United States
    Document type Journal Article
    ZDB-ID 241595-1
    ISSN 1943-3018 ; 0092-7023
    ISSN (online) 1943-3018
    ISSN 0092-7023
    DOI 10.1021/j150452a022
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Book ; Online: A Strategy-Based Framework for Accommodating Reductions in the Defense Budget

    Johnson, Stuart E / Blickstein, Irv / Gompert, David C / Nemfakos, Charles / Thie, Harry J

    2012  

    Keywords Military history ; Defence strategy, planning & research ; Treaties & other sources of international law ; Military engineering ; History ; Political Science ; Technology
    Language English
    Size 1 Online-Ressource
    Publisher RAND Corporation
    Document type Book ; Online
    Note English
    HBZ-ID HT030610809
    ISBN 9780833076861 ; 0833076868
    Database ZB MED Catalogue: Medicine, Health, Nutrition, Environment, Agriculture

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  5. Book ; Online: Alert and Ready

    Paul, Christopher / Thie, Harry J / Webb, Katharine Watkins / Young, Stephanie / Clarke, Colin P

    An Organizational Design Assessment of Marine Corps Intelligence

    2011  

    Keywords Business strategy ; Defence strategy, planning & research ; Espionage & secret services ; Political Science ; Business ; History
    Language English
    Size 1 Online-Ressource
    Publisher RAND Corporation
    Document type Book ; Online
    Note English
    HBZ-ID HT030609424
    ISBN 9780833052605 ; 0833052608
    Database ZB MED Catalogue: Medicine, Health, Nutrition, Environment, Agriculture

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  6. Article ; Online: Introduction to the thematic review series on different levels of genetic regulation of cardiovascular disease.

    de Winther, Menno P J / Dallinga-Thie, Geesje M

    Atherosclerosis

    2018  Volume 281, Page(s) 148–149

    MeSH term(s) Animals ; Cardiovascular Agents/therapeutic use ; Cardiovascular Diseases/drug therapy ; Cardiovascular Diseases/genetics ; DNA Methylation ; Epigenesis, Genetic ; Gene Expression Regulation/drug effects ; Genetic Predisposition to Disease ; Humans ; Phenotype ; Prognosis ; RNA, Long Noncoding/genetics
    Chemical Substances Cardiovascular Agents ; RNA, Long Noncoding
    Language English
    Publishing date 2018-12-22
    Publishing country Ireland
    Document type Editorial ; Introductory Journal Article
    ZDB-ID 80061-2
    ISSN 1879-1484 ; 0021-9150
    ISSN (online) 1879-1484
    ISSN 0021-9150
    DOI 10.1016/j.atherosclerosis.2018.12.014
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Sequential Voxel-Based Leaflet Segmentation of Complex Lipid Morphologies.

    Bruininks, Bart M H / Thie, Albert S / Souza, Paulo C T / Wassenaar, Tsjerk A / Faraji, Shirin / Marrink, Siewert J

    Journal of chemical theory and computation

    2021  Volume 17, Issue 12, Page(s) 7873–7885

    Abstract: As molecular dynamics simulations increase in complexity, new analysis tools are necessary to facilitate interpreting the results. Lipids, for instance, are known to form many complicated morphologies, because of their amphipathic nature, becoming more ... ...

    Abstract As molecular dynamics simulations increase in complexity, new analysis tools are necessary to facilitate interpreting the results. Lipids, for instance, are known to form many complicated morphologies, because of their amphipathic nature, becoming more intricate as the particle count increases. A few lipids might form a micelle, where aggregation of tens of thousands could lead to vesicle formation. Millions of lipids comprise a cell and its organelle membranes, and are involved in processes such as neurotransmission and transfection. To study such phenomena, it is useful to have analysis tools that understand what is meant by emerging entities such as micelles and vesicles. Studying such systems at the particle level only becomes extremely tedious, counterintuitive, and computationally expensive. To address this issue, we developed a method to track all the individual lipid leaflets, allowing for easy and quick detection of topological changes at the mesoscale. By using a voxel-based approach and focusing on locality, we forego costly geometrical operations without losing important details and chronologically identify the lipid segments using the Jaccard index. Thus, we achieve a consistent sequential segmentation on a wide variety of (lipid) systems, including monolayers, bilayers, vesicles, inverted hexagonal phases, up to the membranes of a full mitochondrion. It also discriminates between adhesion and fusion of leaflets. We show that our method produces consistent results without the need for prefitting parameters, and segmentation of millions of particles can be achieved on a desktop machine.
    Language English
    Publishing date 2021-10-05
    Publishing country United States
    Document type Journal Article
    ISSN 1549-9626
    ISSN (online) 1549-9626
    DOI 10.1021/acs.jctc.1c00446
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Bariatric surgery improves postprandial VLDL kinetics and restores insulin-mediated regulation of hepatic VLDL production.

    Yildirim, Vehpi / Ter Horst, Kasper W / Gilijamse, Pim W / van Harskamp, Dewi / Schierbeek, Henk / Jansen, Hans / Schimmel, Alinda Wm / Nieuwdorp, Max / Groen, Albert K / Serlie, Mireille J / van Riel, Natal Aw / Dallinga-Thie, Geesje M

    JCI insight

    2023  Volume 8, Issue 16

    Abstract: Dyslipidemia in obesity results from excessive production and impaired clearance of triglyceride-rich (TG-rich) lipoproteins, which are particularly pronounced in the postprandial state. Here, we investigated the impact of Roux-en-Y gastric bypass (RYGB) ...

    Abstract Dyslipidemia in obesity results from excessive production and impaired clearance of triglyceride-rich (TG-rich) lipoproteins, which are particularly pronounced in the postprandial state. Here, we investigated the impact of Roux-en-Y gastric bypass (RYGB) surgery on postprandial VLDL1 and VLDL2 apoB and TG kinetics and their relationship with insulin-responsiveness indices. Morbidly obese patients without diabetes who were scheduled for RYGB surgery (n = 24) underwent a lipoprotein kinetics study during a mixed-meal test and a hyperinsulinemic-euglycemic clamp study before the surgery and 1 year later. A physiologically based computational model was developed to investigate the impact of RYGB surgery and plasma insulin on postprandial VLDL kinetics. After the surgery, VLDL1 apoB and TG production rates were significantly decreased, whereas VLDL2 apoB and TG production rates remained unchanged. The TG catabolic rate was increased in both VLDL1 and VLDL2 fractions, but only the VLDL2 apoB catabolic rate tended to increase. Furthermore, postsurgery VLDL1 apoB and TG production rates, but not those of VLDL2, were positively correlated with insulin resistance. Insulin-mediated stimulation of peripheral lipoprotein lipolysis was also improved after the surgery. In summary, RYGB resulted in reduced hepatic VLDL1 production that correlated with reduced insulin resistance, elevated VLDL2 clearance, and improved insulin sensitivity in lipoprotein lipolysis pathways.
    MeSH term(s) Humans ; Insulin ; Insulin Resistance ; Lipoproteins, VLDL/metabolism ; Kinetics ; Obesity, Morbid/surgery ; Lipoproteins/metabolism ; Apolipoproteins B/metabolism ; Bariatric Surgery
    Chemical Substances Insulin ; Lipoproteins, VLDL ; Lipoproteins ; Apolipoproteins B
    Language English
    Publishing date 2023-08-22
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 2379-3708
    ISSN (online) 2379-3708
    DOI 10.1172/jci.insight.166905
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Supercritical carbon dioxide extraction of oils from Andean lupin beans: Lab‐scale performance, process scale‐up, and economic evaluation

    Yu, Miao / Kniepkamp, Kai / Thie, Jan Pieter / Witkamp, Geert‐Jan / van Haren, Rob J. F.

    Journal of Food Process Engineering. 2023 Apr., v. 46, no. 4 p.e14289-

    2023  

    Abstract: Oil extraction from Andean lupin beans (Lupinus mutabilis SWEET) via supercritical carbon dioxide (scCO₂) was studied on both lab scale and pilot scale. On the lab scale, the effect of pressure, solvent‐to‐feed ratio (S/F), sample particle size and ... ...

    Abstract Oil extraction from Andean lupin beans (Lupinus mutabilis SWEET) via supercritical carbon dioxide (scCO₂) was studied on both lab scale and pilot scale. On the lab scale, the effect of pressure, solvent‐to‐feed ratio (S/F), sample particle size and temperature on oil yield were evaluated. The oil quality (fatty acid [FA] composition and tocopherol content) were investigated. Five‐hour scCO₂ extraction yielded about 86% oil of Soxhlet extraction (using hexane as solvent). The fraction of unsaturated FA rose with extraction pressure at specific time. High tocopherol contents were detected in oils extracted at low pressure. An increase in temperature was unfavorable to oil and tocopherol yield, thereby confirming the validity for preserving oil extract quality under a mild scCO₂ extraction condition. Oil quality and yield did not have identical optimum settings, opening up possibilities for producing different qualities of oils. Pilot‐scale extraction offered comparable oil yield to lab‐scale extraction at similar S/F ratio. Economic evaluation showed that it is promising to implement industrial scale scCO₂ process for lupin oil extraction. It was predicted that, at a specific industrial scale of extraction (2 × 1000 L, 550 bar, 40°C and S/F of 24), the manufacturing cost of oils got close to actual commercial production cost. PRACTICAL APPLICATION: This study applied an environment‐friendly high‐pressure extraction method, supercritical carbon dioxide (scCO₂) extraction, to separate oils from Andean lupin beans (Lupinus mutabilis SWEET). ScCO₂ extraction can serve as an alternative oil extraction method to conventional ones that use fossil‐derived organic solvents as the extractant. Up‐scaled scCO₂ processing was estimated to be economically viable for commercial lupin oil production.
    Keywords Lupinus mutabilis ; carbon dioxide ; economic evaluation ; economic sustainability ; fatty acids ; hexane ; oils ; particle size ; solid phase extraction ; solvents ; supercritical fluid extraction ; temperature
    Language English
    Dates of publication 2023-04
    Publishing place John Wiley & Sons, Inc.
    Document type Article ; Online
    Note JOURNAL ARTICLE
    ZDB-ID 752358-0
    ISSN 0145-8876
    ISSN 0145-8876
    DOI 10.1111/jfpe.14289
    Database NAL-Catalogue (AGRICOLA)

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  10. Article ; Online: The Role of Heparan Sulfate and Neuropilin 2 in VEGFA Signaling in Human Endothelial Tip Cells and Non-Tip Cells during Angiogenesis In Vitro.

    Dallinga, Marchien G / Habani, Yasmin I / Schimmel, Alinda W M / Dallinga-Thie, Geesje M / van Noorden, Cornelis J F / Klaassen, Ingeborg / Schlingemann, Reinier O

    Cells

    2021  Volume 10, Issue 4

    Abstract: During angiogenesis, vascular endothelial growth factor A (VEGFA) regulates endothelial cell (EC) survival, tip cell formation, and stalk cell proliferation via VEGF receptor 2 (VEGFR2). VEGFR2 can interact with VEGFR2 co-receptors such as heparan ... ...

    Abstract During angiogenesis, vascular endothelial growth factor A (VEGFA) regulates endothelial cell (EC) survival, tip cell formation, and stalk cell proliferation via VEGF receptor 2 (VEGFR2). VEGFR2 can interact with VEGFR2 co-receptors such as heparan sulfate proteoglycans (HSPGs) and neuropilin 2 (NRP2), but the exact roles of these co-receptors, or of sulfatase 2 (SULF2), an enzyme that removes sulfate groups from HSPGs and inhibits HSPG-mediated uptake of very low density lipoprotein (VLDL), in angiogenesis and tip cell biology are unknown. In the present study, we investigated whether the modulation of binding of VEGFA to VEGFR2 by knockdown of
    MeSH term(s) Apoptosis ; Heparitin Sulfate/metabolism ; Human Umbilical Vein Endothelial Cells/metabolism ; Humans ; Lipoproteins, VLDL/metabolism ; Neovascularization, Physiologic ; Neuropilin-2/metabolism ; Signal Transduction ; Sulfatases/metabolism ; Vascular Endothelial Growth Factor A/metabolism ; Vascular Endothelial Growth Factor Receptor-2/metabolism
    Chemical Substances Lipoproteins, VLDL ; Neuropilin-2 ; Vascular Endothelial Growth Factor A ; Heparitin Sulfate (9050-30-0) ; Vascular Endothelial Growth Factor Receptor-2 (EC 2.7.10.1) ; SULF2 protein, human (EC 3.1.6.-) ; Sulfatases (EC 3.1.6.-)
    Language English
    Publishing date 2021-04-16
    Publishing country Switzerland
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2661518-6
    ISSN 2073-4409 ; 2073-4409
    ISSN (online) 2073-4409
    ISSN 2073-4409
    DOI 10.3390/cells10040926
    Database MEDical Literature Analysis and Retrieval System OnLINE

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