scholarly journals Unsupervised logic-based mechanism inference for network-driven biological processes

2021 ◽  
Vol 17 (6) ◽  
pp. e1009035
Author(s):  
Martina Prugger ◽  
Lukas Einkemmer ◽  
Samantha P. Beik ◽  
Perry T. Wasdin ◽  
Leonard A. Harris ◽  
...  
Keyword(s):  
Hamming Distance ◽  
Analytical Techniques ◽  
Regulatory Interactions ◽  
Cellular Processes ◽  
Model Fidelity ◽  
Improve Model ◽  
Before And After ◽  
Unsupervised Approach ◽  
Key Aspects ◽  
Modern Analytical

Modern analytical techniques enable researchers to collect data about cellular states, before and after perturbations. These states can be characterized using analytical techniques, but the inference of regulatory interactions that explain and predict changes in these states remains a challenge. Here we present a generalizable, unsupervised approach to generate parameter-free, logic-based models of cellular processes, described by multiple discrete states. Our algorithm employs a Hamming-distance based approach to formulate, test, and identify optimized logic rules that link two states. Our approach comprises two steps. First, a model with no prior knowledge except for the mapping between initial and attractor states is built. We then employ biological constraints to improve model fidelity. Our algorithm automatically recovers the relevant dynamics for the explored models and recapitulates key aspects of the biochemical species concentration dynamics in the original model. We present the advantages and limitations of our work and discuss how our approach could be used to infer logic-based mechanisms of signaling, gene-regulatory, or other input-output processes describable by the Boolean formalism.

scholarly journals Unsupervised logic-based mechanism inference for network-driven biological processes

2020 ◽  
Author(s):  
Martina Prugger ◽  
Lukas Einkemmer ◽  
Samantha P Beik ◽  
Leonard A Harris ◽  
Carlos F Lopez
Keyword(s):  
Hamming Distance ◽  
Analytical Techniques ◽  
Regulatory Interactions ◽  
Cellular Processes ◽  
Model Fidelity ◽  
Ongoing Work ◽  
Improve Model ◽  
Before And After ◽  
Unsupervised Approach ◽  
Modern Analytical

Modern analytical techniques enable researchers to collect data about cellular states, before and after perturbations. These states can be characterized using analytical techniques, but the inference of regulatory interactions that explain and predict changes in these states remains a challenge. Here we present a generalizable unsupervised approach to generate parameter-free, logic-based mechanistic hypotheses of cellular processes, described by multiple discrete states. Our algorithm employs a Hamming-distance based approach to formulate, test, and identify, the best mechanism that links two states. Our approach comprises two steps. First, a model with no prior knowledge except for the mapping between initial and attractor states is built. Second, we employ biological constraints to improve model fidelity. Our algorithm automatically recovers the relevant dynamics for the explored models and recapitulates all aspects of the original models biochemical species concentration dynamics. We then conclude by placing our results in the context of ongoing work in the field and discuss how our approach could be used to infer mechanisms of signaling, gene-regulatory, and any other input-output processes describable by logic-based mechanisms.

scholarly journals Characterization and Identification of Varnishes on Copper Alloys by Means of UV Imaging and FTIR

Coatings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 298
Author(s):  
Miriam Truffa Giachet ◽  
Julie Schröter ◽  
Laura Brambilla
Keyword(s):  
Copper Alloys ◽  
Analytical Techniques ◽  
Experimental Methodology ◽  
Artificial Ageing ◽  
Non Invasive ◽  
Uv Imaging ◽  
Before And After ◽  
The Comparative Study ◽  
The 19Th Century ◽  
Analytical Tools

The application of varnishes on the surface of metal objects has been a very common practice since antiquity, both for protective and aesthetic purposes. One specific case concerns the use of tinted varnishes on copper alloys in order to mimic gilding. This practice, especially flourishing in the 19th century for scientific instruments, decorative objects, and liturgical items, results in large museum collections of varnished copper alloys that need to be preserved. One of the main challenges for conservators and restorers deals with the identification of the varnishes through non-invasive and affordable analytical techniques. We hereby present the experimental methodology developed in the framework of the LacCA and VERILOR projects at the Haute École ARC of Neuchâtel for the identification of gold varnishes on brass. After extensive documentary research and analytical campaigns on varnished museum objects, various historic shellac-based varnishes were created and applied by different methods on a range of brass substrates with different finishes. The samples were then characterized by UV imaging and infrared spectroscopy before and after artificial ageing. The comparative study of these two techniques was performed for different thicknesses of the same varnish and for different shellac grades in order to implement an identification methodology based on simple non-invasive examination and analytical tools, which are accessible to conservators.

scholarly journals Rethinking SME default prediction: a systematic literature review and future perspectives

2021 ◽  
Author(s):  
Francesco Ciampi ◽  
Alessandro Giannozzi ◽  
Giacomo Marzi ◽  
Edward I. Altman
Keyword(s):  
Literature Review ◽  
Systematic Literature Review ◽  
Global Financial Crisis ◽  
Analytical Techniques ◽  
Future Research ◽  
Finance Management ◽  
Default Prediction ◽  
Emerging Issues ◽  
Medium Enterprise ◽  
Modern Analytical

AbstractOver the last dozen years, the topic of small and medium enterprise (SME) default prediction has developed into a relevant research domain that has grown for important reasons exponentially across multiple disciplines, including finance, management, accounting, and statistics. Motivated by the enormous toll on SMEs caused by the 2007–2009 global financial crisis as well as the recent COVID-19 crisis and the consequent need to develop new SME default predictors, this paper provides a systematic literature review, based on a statistical, bibliometric analysis, of over 100 peer-reviewed articles published on SME default prediction modelling over a 34-year period, 1986 to 2019. We identified, analysed and reviewed five streams of research and suggest a set of future research avenues to help scholars and practitioners address the new challenges and emerging issues in a changing economic environment. The research agenda proposes some new innovative approaches to capture and exploit new data sources using modern analytical techniques, like artificial intelligence, machine learning, and macro-data inputs, with the aim of providing enhanced predictive results.

Preface

2006 ◽  
Vol 78 (8) ◽  
pp. iv
Author(s):  
Richard J. Cogdell
Keyword(s):  
International Symposium ◽  
De Novo ◽  
Analytical Techniques ◽  
Carotenoid Biosynthesis ◽  
Annual Growth Rate ◽  
Chemical Company ◽  
Cellular Processes ◽  
Poster Sessions ◽  
14Th International Symposium ◽  
Oral Communications

The 14th International Symposium on Carotenoids was held in Edinburgh, Scotland, UK 17-22 July 2005, under the chairmanship of Dr. George Britton. The International Symposium on Carotenoids is the official symposium for the International Carotenoid Society (http://carotenoidsociety.org), which supported the symposium as did IUPAC. Financial support was gratefully received from DSM Nutritional Products, BASF Ag, Cognis Deutschland, Fuji Chemical Company Ltd., Inexa Industria Extractora CA, Valensa International, Nu Skin International Inc., Cargill Inc., The Alcon Foundation Inc., Kemin Health, Access Business Group, and LycoRed Natural Products Industries Ltd.The first International Symposium took place in Trondheim, Norway in 1966, and such meetings have continued at three-year intervals since then. Over that period of almost 40 years, the carotenoids field has expanded tremendously and diversified into many fields of study, especially human nutrition and health. There have also been continued advances in our understanding of the roles of carotenoids in photosynthesis and photochemistry, the regulation of their formation, de novo chemical synthesis, and the analytical techniques available for detailed structural analyses. The commercial importance of carotenoids has also significantly increased over the years; the current market was estimated to be around $887 million for 2004 and is expected to rise at an average annual growth rate of 2.9 % to just over $1 billion.These areas were fully reflected in the 220 invited lectures, oral communications, and poster sessions. The seven articles that appear in this issue embody the themes of the symposium, namely:- Carotenoids and Health: a series of themed sessions focusing on protection against disease, the eye, molecular and cellular processes, and nutrition- Carotenoid Oxidation and Breakdown Products and Metabolites- Carotenoids in Photosynthesis- Carotenoid Biosynthesis- Commercial Production and Applications- Carotenoids and Nature: ecology, etc.- Molecular Interactions of CarotenoidsFinally, we would like to thank everyone who contributed to a most successful symposium, including the local organizing committee, and look forward to the next meeting in 2008, which will be held in Okinawa, Japan and will be chaired by Prof. Hideki Hashimoto.Richard J. CogdellPeter M. BramleyConference Editors

Absorption of L-alanine and other dissolved nutrients by the spines of Paracentrotus lividus (Echinoidea)

1977 ◽  
Vol 57 (4) ◽  
pp. 1031-1045 ◽  
Author(s):  
M. E. de Burgh ◽  
A. B. West ◽  
F. Jeal
Keyword(s):  
Amino Acids ◽  
Organic Molecules ◽  
Marine Invertebrates ◽  
Analytical Techniques ◽  
Paracentrotus Lividus ◽  
Direct Absorption ◽  
Dissolved Nutrients ◽  
Recent Developments ◽  
Modern Analytical

The possibility that marine invertebrates might obtain part of their nutritional requirements by direct absorption of dissolved molecules through the epidermis has recently received considerable attention. This revival of interest in a field which had been virtually abandoned since the early part of the century was led by the findings of Stephens & Schinske (1957, 1958, 1961). Modern analytical techniques have revealed that the amount of dissolved nutrients in coastal waters is much greater than was formerly realized; total amino acids have been recorded in concentrations of up to 10-4 mole/litre in south-east Alaskan waters (Schell, 1974) and 7 x 10-5 mole/litre off Helgoland (Bohling, 1970). Direct absorption of amino acids has been conclusively established in several phyla (see reviews by Stephens, 1968,1972), and one of the major aims of current research is to show that dissolved organic molecules taken up from available concentrations could be of nutritional significance. Recent developments concerning the possible roles of uptake in marine ecosystems have been reviewed by West, de Burgh & Jeal (1977).

Molecular Characterization of Diesel Fuels Using Modern Analytical Techniques

2020 ◽  
pp. 61-76
Author(s):  
C. S. Hsu ◽  
G. J. Dechert ◽  
D. J. Abbott ◽  
M. W. Genowitz ◽  
R. Barbour
Keyword(s):  
Molecular Characterization ◽  
Analytical Techniques ◽  
Diesel Fuels ◽  
Modern Analytical

Science of Art and Analysis: A Mixture for Undergraduate Non-Specialists

1992 ◽  
Vol 267 ◽  
Author(s):  
W. Stanley Taft ◽  
James W. Mayer
Keyword(s):  
Physical Properties ◽  
Computer Science ◽  
Undergraduate Students ◽  
Analytical Methods ◽  
Art History ◽  
Analytical Techniques ◽  
Cornell University ◽  
The Third ◽  
Works Of Art ◽  
Modern Analytical

ABSTRACTAt Cornell University we are in the third year of teaching an interdisciplinary, undergraduate course on the physical properties and structures of works of Art, and the modern analytical methods used to investigate them: Art, Isotopes, and Analysis. The challenge is to explain concepts familiar to museum scientists and conservators to a group of 150 undergraduate students with a background that ranges from Art History to Computer Science. Painting techniques (Fresco, Tempera, Oil, etc.) are demonstrated to the class. The analytical techniques involve the interactions of electrons, photons, ions and neutrons with pigments and other materials. This instructional approach serves as an introduction to published analyses of works of art.

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