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398 results on '"Geissler, C."'

2. Applying separative non-negative matrix factorization to extra-financial data

Author

Fogel, P, Geissler, C, Cotte, P, and Luta, G

Subjects
Quantitative Finance - Computational Finance, Statistics - Machine Learning
Abstract

We present here an original application of the non-negative matrix factorization (NMF) method, for the case of extra-financial data. These data are subject to high correlations between co-variables, as well as between observations. NMF provides a much more relevant clustering of co-variables and observations than a simple principal component analysis (PCA). In addition, we show that an initial data separation step before applying NMF further improves the quality of the clustering.

Published
2022

3. Online Bayesian inference for multiple changepoints and risk assessment

Author

Sorba, Olivier and Geissler, C

Subjects
Computer Science - Machine Learning, Statistics - Methodology
Abstract

The aim of the present study is to detect abrupt trend changes in the mean of a multidimensional sequential signal. Directly inspired by papers of Fernhead and Liu ([4] and [5]), this work describes the signal in a hierarchical manner : the change dates of a time segmentation process trigger the renewal of a piece-wise constant emission law. Bayesian posterior information on the change dates and emission parameters is obtained. These estimations can be revised online, i.e. as new data arrive. This paper proposes explicit formulations corresponding to various emission laws, as well as a generalization to the case where only partially observed data are available. Practical applications include the returns of partially observed multi-asset investment strategies, when only scant prior knowledge of the movers of the returns is at hand, limited to some statistical assumptions. This situation is different from the study of trend changes in the returns of individual assets, where fundamental exogenous information (news, earnings announcements, controversies, etc.) can be used.

Published
2021

8. Recommendations on compiling test datasets for evaluating artificial intelligence solutions in pathology

Author

Homeyer, A., Geißler, C., Ole Schwen, L., Zakrzewski, F., Evans, T., Strohmenger, K., Westphal, M., David Bülow, R., Kargl, M., Karjauv, A., Munné-Bertran, I., Orge Retzlaff, C., Romero-López, A., Sołtysiński, T., Plass, M., Carvalho, R., (0000-0002-4974-230X) Steinbach, P., Lan, Y.-C., Bouteldja, N., Haber, D., Rojas-Carulla, M., Vafaei Sadr, A., Kraft, M., Krüger, D., Fick, R., Lang, T., Boor, P., Müller, H., Hufnagl, P., Zerbe, N., Homeyer, A., Geißler, C., Ole Schwen, L., Zakrzewski, F., Evans, T., Strohmenger, K., Westphal, M., David Bülow, R., Kargl, M., Karjauv, A., Munné-Bertran, I., Orge Retzlaff, C., Romero-López, A., Sołtysiński, T., Plass, M., Carvalho, R., (0000-0002-4974-230X) Steinbach, P., Lan, Y.-C., Bouteldja, N., Haber, D., Rojas-Carulla, M., Vafaei Sadr, A., Kraft, M., Krüger, D., Fick, R., Lang, T., Boor, P., Müller, H., Hufnagl, P., and Zerbe, N.

Abstract

Artificial intelligence (AI) solutions that automatically extract information from digital histology images have shown great promise for improving pathological diagnosis. Prior to routine use, it is important to evaluate their predictive performance and obtain regulatory approval. This assessment requires appropriate test datasets. However, compiling such datasets is challenging and specific recommendations are missing. A committee of various stakeholders, including commercial AI developers, pathologists, and researchers, discussed key aspects and conducted extensive literature reviews on test datasets in pathology. Here, we summarize the results and derive general recommendations on compiling test datasets. We address several questions: Which and how many images are needed? How to deal with low-prevalence subsets? How can potential bias be detected? How should datasets be reported? What are the regulatory requirements in different countries? The recommendations are intended to help AI developers demonstrate the utility of their products and to help pathologists and regulatory agencies verify reported performance measures. Further research is needed to formulate criteria for sufficiently representative test datasets so that AI solutions can operate with less user intervention and better support diagnostic workflows in the future.

Published
2022

9. Endothelial ENPP2 (Ectonucleotide Pyrophosphatase/Phosphodiesterase 2) Increases Atherosclerosis in Female and Male Mice

Author

Karshovska, E., Mohibullah, R., Zhu, M.Y., Zahedi, F., Thomas, D., Magkrioti, C., Geissler, C., Megens, R.T.A., Bianchini, M., Nazari-Jahantigh, M., Ferreiros, N., Aidinis, V., Schober, A., Karshovska, E., Mohibullah, R., Zhu, M.Y., Zahedi, F., Thomas, D., Magkrioti, C., Geissler, C., Megens, R.T.A., Bianchini, M., Nazari-Jahantigh, M., Ferreiros, N., Aidinis, V., and Schober, A.

Abstract

Background: Maladapted endothelial cells (ECs) secrete ENPP2 (ectonucleotide pyrophosphatase/phosphodiesterase 2; autotaxin)-a lysophospholipase D that generates lysophosphatidic acids (LPAs). ENPP2 derived from the arterial wall promotes atherogenic monocyte adhesion induced by generating LPAs, such as arachidonoyl-LPA (LPA20:4), from oxidized lipoproteins. Here, we aimed to determine the role of endothelial ENPP2 in the production of LPAs and atherosclerosis. Methods: We quantified atherosclerosis in mice harboring loxP-flanked Enpp2 alleles crossed with Apoe(-/-) mice expressing tamoxifen-inducible Cre recombinase under the control of the EC-specific bone marrow X kinase promoter after 12 weeks of high-fat diet feeding. Results: A tamoxifen-induced EC-specific Enpp2 knockout decreased atherosclerosis, accumulation of lesional macrophages, monocyte adhesion, and expression of endothelial CXCL (C-X-C motif chemokine ligand) 1 in male and female Apoe(-/-) mice. In vitro, ENPP2 mediated the mildly oxidized LDL (low-density lipoprotein)-induced expression of CXCL1 in aortic ECs by generating LPA20:4, palmitoyl-LPA (LPA16:0), and oleoyl-LPA (LPA18:1). ENPP2 and its activity were detected on the endothelial surface by confocal imaging. The expression of endothelial Enpp2 established a strong correlation between the plasma levels of LPA16:0, stearoyl-LPA (LPA18:0), and LPA18:1 and plaque size and a strong negative correlation between the LPA levels and ENPP2 activity in the plasma. Moreover, endothelial Enpp2 knockout increased the weight of high-fat diet-fed male Apoe(-/-) mice. Conclusions: We demonstrated that the expression of ENPP2 in ECs promotes atherosclerosis and endothelial inflammation in a sex-independent manner. This might be due to the generation of LPA20:4, LPA16:0, and LPA18:1 from mildly oxidized lipoproteins on the endothelial surface.

Published
2022

16. Tabulae phytographicae, analysin generum plantarum exhibentes,

Author

Gessner, Johannes, 1709-1790, Geissler, C. G. (Christian Gottleib), 1729-1814, Schinz, Christoph Salomon, 1764-1847, New York Botanical Garden, LuEsther T. Mertz Library, Gessner, Johannes, 1709-1790, Geissler, C. G. (Christian Gottleib), 1729-1814, and Schinz, Christoph Salomon, 1764-1847

Subjects
Pictorial works, Plants
Published
1795

28. Relationship between feeding pattern and body mass index in 220 free-living people in four age groups

Author

Summerbell, C.D., Moody, R.C., Shanks, J., Stock, M.J., and Geissler, C.

Subjects
Food habits -- Health aspects, Food consumption -- Physiological aspects, Body weight -- Analysis, Nutrition -- Analysis
Abstract

The relationship between feeding patterns and body mass index (BMI) is stronger in the elderly and working age groups as compared to adolescents and middle-age groups. Greater energy consumption at breakfast is associated with a lower BMI for adolescents and middle aged people, which may be attributed to under-recording of habitual energy consumption by the obese and females. BMI is significantly related to the reported energy intake only in the working class group. Gorging of food is commonly reported by all age groups except the working class, indicating under-reporting of habitual nibbling behavior.

Published
1996

31. Sources of energy from meals versus snacks in 220 people in four age groups

Author

Summerbell, C.D., Moody, R.C., Shanks, J., Stock, M.J., and Geissler, C.

Subjects
British -- Food and nutrition, Sugars in human nutrition -- Research
Abstract

A study of the nutrient composition in food consumed by 88 elderly, 40 middle-aged, 59 young adults and 33 teens revealed that the overall food consumed by the British populace contained excessive levels of sugar. Snacks such as chocolates and squashes, consumed in large quantities by the youth, contained large amounts of sugar. Meals favored by the elderly contained proteins and fats and minimal quantities of sugar.

Published
1995

32. Abstracts of scientific papers second international symposium on central nervous system monitoring: September 8–9, 1989 Gmunden, Austria

Author

Gaab, M. R., Trost, H. A., Lorenz, M., Seegers, K., Heuser, D., Fitch, W., Baethmann, A., Speckmann, E. -J., Lehmenkühler, A., Pöppelmann, Th., Bingmann, D., Rabow, L., Bergenheim, T., Bålfors, Eva, Urban, G., Keplinger, F., Kohl, F., Kuttner, H., Jobst, G., Pittner, F., Schalkhammer, T., Mann-Buxbaum, E., Litscher, G., Steiler, E., Pfurtschcller, G., Schwarz, G., Hinrichs, H., Feistner, H., Künkel, H., Wieser, H. G., Isler, P., Witztum, A., Siegel, A., Merles, N., Möllmann, M., Penner, M., Schoeppner, H., Hohenberger, K., Daub, D., Freye, E., Grabitz, K., Sandmann, W., Haass, A., Ladurner, G., Teasdale, G., Weis, M., Hilz, M. J., Claus, D., Neundörfer, B., Druschky, K. F., Litscher, G., Pfurtscheller, G., Heinze, H.-J, Künkcl, H., Symon, L., Cooper, Gough, Rampil, I. J., Bosco, M., Adducci, E., Gualtieri, E., Amato, A., Lacava, E., Mascia, A., Bonomo, V., Dinkel, M., Kamp, H.-D, Schweiger, H., Jaksche, H., Schwerdtfeger, K., Loew, F., Rath, S. A., Klein, H. J., Kühn, J., Fritz, W., Thiel, A., Russ, W., Hcmpelmann, G., Morawetz, R. F., Schlager, A., Lugcr, Th. J., Vajsar, J., Hopkins, Anne J., Ronen, G. M., Kuppe, H., Porte, T., Dannenberger, R., Götz, C., Adt, M., Schmucker, P., Landi, A., Colombo, F., De Luca, G. P., Fornezza, U., Benedctti, A., Bruno, R., Zamparctti, N., Engelhardt, W., Drösler, S., Dierks, T., Maurer, K., Hecht, U., Lehmkuhl, P., Pichlmayr, I., Cheng-hui, Li, Shi-ao, Jin, Cheng-hui, Li, Shi-ao, Jin, Theissen, J., Zander, J., Moberg, D., Bell, R., Miller, S. B., Pohl, S., Hühnefeld, D., Henries, H.-J, Jantzen, J.-P, Eberle, B., Dick, W., Wallenfang, T., Fuzes, I., Geissler, C., Schregel, W., Cunitz, G., Fomezza, U., Volpin, L., Zamperetti, N., Demo, P., Digito, A., Barbacini, S., Zamperetti, N., and Lacquaniti, L.

Published
1990
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33. Impact of large-dose vitamin A supplementation on childhood diarrhoea, respiratory disease and growth

Author

Cheng Lie, Chang Ying, Wang En-Lin, Brun, T., and Geissler, C.

Subjects
Vitamin A in human nutrition -- Research, Diarrhea in children -- Care and treatment, Pediatric respiratory diseases -- Care and treatment, Vitamin A -- Health aspects
Abstract

The incidence of diarrhea and respiratory infection and the subsequent effect on growth of large dose vitamin A supplementation was studied in 172 0.5 to 3.0-year-old children from Lai Yuan county, Hebei Province, China. Results show that there was a significant decrease in the incidence of diarrhea and respiratory disease in the experimental group given 200,000 IU vitamin A as compared to the control group.No significant differences in growth were observed.

Published
1993

36. PS1331 MYELOMONOCYTIC SKEWING IN CHRONIC MYELOMONOCYTIC LEUKEMIA: PHENOTYPIC, GENOTYPIC AND BIOLOGIC FEATURES AND IMPACT ON SURVIVAL

Author

Geissler, K., primary, Jäger, E., additional, Barna, A., additional, Gurbisz, M., additional, Marschon, R., additional, Graf, T., additional, Graf, E., additional, Borjan, B., additional, Jilch, R., additional, Geissler, C., additional, Hörmann, G., additional, Esterbauer, H., additional, Schwarzinger, I., additional, Nösslinger, T., additional, Pfeilstöcker, M., additional, Tüchler, H., additional, Reisner, R., additional, Sliwa, T., additional, Keil, F., additional, Bettelheim, P., additional, Machherndl-Spandl, S., additional, Zach, O., additional, Weltermann, A., additional, Heibl, S., additional, Thaler, J., additional, Zebisch, A., additional, Sill, H., additional, Stauder, R., additional, Webersinke, G., additional, Petzer, A., additional, Kusec, R., additional, Ulsperger, E., additional, Schneeweiss, B., additional, Berger, J., additional, Öhler, L., additional, Germing, U., additional, Sperr, W.R., additional, Knöbl, P., additional, Jäger, U., additional, and Valent, P., additional

Published
2019
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39. Combined Therapy of two RTKs: Erbitux und BGJ398 treatment in HNSCC cell lines

Author

Geißler, C, Gabrielpillai, J, Stein, S, Diensthuber, M, Wagenblast, J, and Stöver, T

Subjects
ddc: 610, 610 Medical sciences, Medicine
Abstract

Head and neck squamous cell carcinoma (HNSCC) derive from the mucosa of the aerodigestive area and still have worse prognoses. Despite of new treatment strategies like the epithelial growth factor receptor (EGFR) antibody Erbitux the survival rates have not increased yet. The native mucosa expresses several receptor tyrosine kinases (RTKs) like EGFR and fibroblast growth factor receptors (FGFRs) that regulate survival and proliferation. We hypnotized that the tumor cells can switch between the different RTKs to overcome the therapy. To improve therapy in HNSCC, this study determined the effectiveness of a combined treatment targeting EGFR and FGFR. In an in-vitro drug trial Detroit-562, CAL-27 and PJ-15 cell lines were studied. BGJ398 (Novartis) that inhibits FGFRs and/or Erbitux (Merck) treatment was performed. Apoptosis was verified by caspases activity. The expression of the different RTKs was determined by immunocytochemistry and flow cytometry. The cell lines expressed EGFR, KGFR and low amounts of FGFR1 and FGFR3. In all tested cell lines, the treatment with BGJ398 or Erbitux significantly reduce survival and proliferation. The combination of both drugs enhanced the effect at lower concentrations compared to the single drug treatment. This study demonstrated that the combination of BGJ-398 and Erbitux is a promising treatment regime for HNSCCs. In the future, the reduction in drug concentrations may reduce side effects. Supported by: Novartis Pharma GmbH Der Erstautor gibt keinen Interessenkonflikt an., GMS Current Posters in Otorhinolaryngology - Head and Neck Surgery; 13:Doc229

Published
2017

40. Somatotropin verbessert das Wachstum von Stammzellkolonien des neonatalen Spiralganglions

Author

Diensthuber, M, Gabrielpillai, J, Stock, B, Geissler, C, and Stöver, T

Subjects
ddc: 610, 610 Medical sciences, Medicine
Abstract

Einleitung: Das Wachstumshormon Somatotropin ist ein entscheidender Faktor im Rahmen der embryonalen Entwicklung des zentralen Nervensystems. Kürzlich wurde auch eine Bedeutung dieses Proteohormons für das Überleben neuraler Stammzellen des Gehirns nachgewiesen. Ziel dieser Arbeit war[zum vollständigen Text gelangen Sie über die oben angegebene URL], 88. Jahresversammlung der Deutschen Gesellschaft für Hals-Nasen-Ohren-Heilkunde, Kopf- und Hals-Chirurgie

Published
2017
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