scholarly journals k-Shape Clustering for Extracting Macro-patterns in Intracranial Pressure Signals

Author(s):  
Isabel Martinez-Tejada ◽  
Casper Schwartz Riedel ◽  
Marianne Juhler ◽  
Morten Andresen ◽  
Jens E. Wilhjelm

Abstract Background: Intracranial pressure (ICP) monitoring is a core component of neurosurgical diagnostics. With the introduction of telemetric monitoring devices in the last years, ICP monitoring has become feasible in a broader clinical setting including monitoring during full mobilization and at home, where a greater diversity of ICP waveforms are present. The need for identification of these variations, the so-called macro-patterns lasting seconds to minutes - emerges as a potential tool for better understanding the physiological underpinnings of patient symptoms. Methods: We introduce a new methodology that serves as a foundation for future automatic macro-pattern identification in the ICP signal to comprehensively understand the appearance and distribution of these macro-patterns in the ICP signal and their clinical significance. Specifically, we describe an algorithm based on k-Shape clustering to build a standard library of such macro-patterns. Results: In total, seven macro-patterns were extracted from the ICP signals. This macro-pattern library may be used as a basis for the classification of new ICP variation distributions based on clinical disease entities.Conclusions: We provide the starting point for future researchers to use a computational approach to characterize ICP recordings from a wide cohort of disorders.

2018 ◽  
Vol 21 (2) ◽  
pp. 125-137
Author(s):  
Jolanta Stasiak ◽  
Marcin Koba ◽  
Marcin Gackowski ◽  
Tomasz Baczek

Aim and Objective: In this study, chemometric methods as correlation analysis, cluster analysis (CA), principal component analysis (PCA), and factor analysis (FA) have been used to reduce the number of chromatographic parameters (logk/logkw) and various (e.g., 0D, 1D, 2D, 3D) structural descriptors for three different groups of drugs, such as 12 analgesic drugs, 11 cardiovascular drugs and 36 “other” compounds and especially to choose the most important data of them. Material and Methods: All chemometric analyses have been carried out, graphically presented and also discussed for each group of drugs. At first, compounds’ structural and chromatographic parameters were correlated. The best results of correlation analysis were as follows: correlation coefficients like R = 0.93, R = 0.88, R = 0.91 for cardiac medications, analgesic drugs, and 36 “other” compounds, respectively. Next, part of molecular and HPLC experimental data from each group of drugs were submitted to FA/PCA and CA techniques. Results: Almost all results obtained by FA or PCA, and total data variance, from all analyzed parameters (experimental and calculated) were explained by first two/three factors: 84.28%, 76.38 %, 69.71% for cardiovascular drugs, for analgesic drugs and for 36 “other” compounds, respectively. Compounds clustering by CA method had similar characteristic as those obtained by FA/PCA. In our paper, statistical classification of mentioned drugs performed has been widely characterized and discussed in case of their molecular structure and pharmacological activity. Conclusion: Proposed QSAR strategy of reduced number of parameters could be useful starting point for further statistical analysis as well as support for designing new drugs and predicting their possible activity.


2021 ◽  
Vol 2021 (2) ◽  
Author(s):  
Tomáš Brauner

Abstract We initiate the classification of nonrelativistic effective field theories (EFTs) for Nambu-Goldstone (NG) bosons, possessing a set of redundant, coordinate-dependent symmetries. Similarly to the relativistic case, such EFTs are natural candidates for “exceptional” theories, whose scattering amplitudes feature an enhanced soft limit, that is, scale with a higher power of momentum at long wavelengths than expected based on the mere presence of Adler’s zero. The starting point of our framework is the assumption of invariance under spacetime translations and spatial rotations. The setup is nevertheless general enough to accommodate a variety of nontrivial kinematical algebras, including the Poincaré, Galilei (or Bargmann) and Carroll algebras. Our main result is an explicit construction of the nonrelativistic versions of two infinite classes of exceptional theories: the multi-Galileon and the multi-flavor Dirac-Born-Infeld (DBI) theories. In both cases, we uncover novel Wess-Zumino terms, not present in their relativistic counterparts, realizing nontrivially the shift symmetries acting on the NG fields. We demonstrate how the symmetries of the Galileon and DBI theories can be made compatible with a nonrelativistic, quadratic dispersion relation of (some of) the NG modes.


2021 ◽  
Vol 1 ◽  
pp. 51-60
Author(s):  
Peter Welzbacher ◽  
Gunnar Vorwerk-Handing ◽  
Eckhard Kirchner

AbstractThe importance of considering disturbance factors in the product development process is often emphasized as one of the key factors to a functional and secure product. However, there is only a small number of tools to support the developer in the identification of disturbance factors and none of them yet ensures that the majority of occurring disturbance factors is considered. Thus, it is the aim of this contribution to provide a tool in form of a control list for the systematic identification of disturbance factors. At the beginning of this contribution, the terms “disturbance factor” and “uncertainty” are defined based on a literature review and different approaches for the classification of uncertainty are presented. Subsequently, the fundamentals of multipole based model theory are outlined. Moreover, a first approach in terms of a control list for a systematic identification of disturbance factors is discussed. Based on the discussed approach and taking the identified weaknesses as a starting point, a control list is presented that combines the existing basic concept of the control list with the fundamentals of multipole based model theory.


2019 ◽  
Vol 25 (5) ◽  
pp. 972-994 ◽  
Author(s):  
Michael Fellmann ◽  
Agnes Koschmider ◽  
Ralf Laue ◽  
Andreas Schoknecht ◽  
Arthur Vetter

Purpose Patterns have proven to be useful for documenting general reusable solutions to a commonly occurring problem. In recent years, several different business process management (BPM)-related patterns have been published. Despite the large number of publications on this subject, there is no work that provides a comprehensive overview and categorization of the published business process model patterns. The purpose of this paper is to close this gap by providing a taxonomy of patterns as well as a classification of 89 research works. Design/methodology/approach The authors analyzed 280 research articles following a structured iterative procedure inspired by the method for taxonomy development from Nickerson et al. (2013). Using deductive and inductive reasoning processes embedded in concurrent as well as joint research activities, the authors created a taxonomy of patterns as well as a classification of 89 research works. Findings In general, the findings extend the current understanding of BPM patterns. The authors identify pattern categories that are highly populated with research works as well as categories that have received far less attention such as risk and security, the ecological perspective and process architecture. Further, the analysis shows that there is not yet an overarching pattern language for business process model patterns. The insights can be used as starting point for developing such a pattern language. Originality/value Up to now, no comprehensive pattern taxonomy and research classification exists. The taxonomy and classification are useful for searching pattern works which is also supported by an accompanying website complementing the work. In regard to future research and publications on patterns, the authors derive recommendations regarding the content and structure of pattern publications.


2014 ◽  
Vol 14 (6) ◽  
pp. 674-681 ◽  
Author(s):  
Steven A. Wall ◽  
Gregory P. L. Thomas ◽  
David Johnson ◽  
Jo C. Byren ◽  
Jayaratnam Jayamohan ◽  
...  

Object The presence of raised intracranial pressure (ICP) in untreated nonsyndromic, isolated sagittal craniosynostosis (SC) is an important functional indication for surgery. Methods A retrospective review was performed of all 284 patients presenting with SC to the Oxford Craniofacial Unit between 1995 and 2010. Results Intraparenchymal ICP monitoring was performed in 39 children following a standard unit protocol. Monitoring of ICP was offered for all patients in whom nonoperative management was considered on the basis of minimal deformity or in cases in which parents were reluctant to agree to corrective surgery. These patients presented at an older age than the rest of the cohort (mean age 56 months), with marked scaphocephaly (16/39, 41%), mild scaphocephaly (11, 28%), or no scaphocephalic deformity (12, 31%). Raised ICP was found in 17 (44%) patients, with no significant difference in its incidence among the 3 different deformity types. Raised ICP was not predicted by the presence of symptoms of ICP or developmental delay or by ophthalmological or radiological findings. Conclusions The incidence of raised ICP in SC reported here is greater than that previously published in the literature. The lack of a reliable noninvasive method to identify individuals with elevated ICP in SC mandates consideration of intraparenchymal ICP monitoring in all patients for whom nonoperative management is contemplated.


2002 ◽  
Vol 85 (1) ◽  
pp. 168-210 ◽  
Author(s):  
MARIUS DADARLAT ◽  
SØREN EILERS

We employ results from KK-theory, along with quasidiagonality techniques, to obtain wide-ranging classification results for nuclear C*-algebras. Using a new realization of the Cuntz picture of the Kasparov groups we show that two morphisms inducing equal KK-elements are approximately stably unitarily equivalent. Using K-theory with coefficients to associate a partial KK-element to an approximate morphism, our result is generalized to cover such maps. Conversely, we study the problem of lifting a (positive) partial KK-element to an approximate morphism. These results are employed to obtain classification results for certain classes of quasidiagonal C*-algebras introduced by H. Lin, and to reprove the classification of purely infinite simple nuclear C*-algebras of Kirchberg and Phillips. It is our hope that this work can be the starting point of a unified approach to the classification of nuclear C*-algebras.2000 Mathematical Subject Classification: primary 46L35; secondary 19K14, 19K35, 46L80.


2013 ◽  
Vol 4 (2) ◽  
Author(s):  
Dušan Ignjatović ◽  
Nataša Ćuković Ignjatović ◽  
Milica Jovanović Popović

Serbia’s Law on Planning and Building has imposed the topics of energy efficiency in building sector, requiring adequate policy making and providing a starting point for improvement of the current situation in this field. Considering the fact that there are more than 3.200.000 housing units without any statistical classification a need arose for establishing a national building typology as a starting point for further decision making and appropriate activities definition regarding the existing housing stock. After joining EU TABULA (Typology Approach for Building Stock Energy Assessment) project, methodologies and approaches of the European countries have been analysed providing a common experience, at the same illustrating a need for identification and classification of local characteristics. In order to obtain adequate data a comprehensive survey has been conducted, providing a starting point for creation of typology. The National Typology has identified typical “model” buildings and defined the levels of improvement ranging from standard (according to the current law) to the low-energy level. The paper explains the methodology, procedures and local characteristics of the process and gives an insight in the activity describing the problems and potentials of the approach.


2020 ◽  
Vol 3 (2) ◽  
pp. 155
Author(s):  
Sukmawati Syarif ◽  
A. Muflihunna ◽  
Zainal Abidin ◽  
Masdiana Tahir

Menstruation is a physiological change in a woman's body that occurs periodically and is influenced by reproductive hormones either FSH-Estrogen or LH-Progesterone. In women, this usually occurs every month between teens to menopause, and lasts around 7-28 days. Knowing the characteristics of menstruation early is a very important thing to know because it is an early learning about the reproductive system and their health. Blood type is an inherited antigen on the surface of red blood cells. The two most important types of blood classification to know are the classification of ABO and Rhesus (Rh factor). Blood type examination is an activity that is sometimes overlooked by the community, in this case the needs of the Blood Type are carried out for clinical purposes such as: blood transfusions, preventing transfusion complications, and for pregnant women. According to empirical data obtained in 2017 the level of understanding of menstruation and blood type in primary schools is very low. For this reason, efforts are made to provide education and information as well as checks on children from an early age as a starting point for character building in improving education and knowledge in general and specifically regarding health


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