scholarly journals Modelling Framework and Assistive Device for Peripheral Intravenous Injections

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Kin F. Kam ◽  
Martin P. Robinson ◽  
Mathew A. Gilbert ◽  
Adar Pelah
Keyword(s):  
Invasive Procedure ◽  
Assistive Device ◽  
Mathematical Framework ◽  
Needle Guidance ◽  
Intravenous Injections ◽  
Basic Assumptions ◽  
Modelling Framework ◽  
Video Recordings ◽  
Skilled Practitioner ◽  
Robotic Automation

Abstract Intravenous access for blood sampling or drug administration that requires peripheral venepuncture is perhaps the most common invasive procedure practiced in hospitals, clinics and general practice surgeries.We describe an idealised mathematical framework for modelling the dynamics of the peripheral venepuncture process. Basic assumptions of the model are confirmed through motion analysis of needle trajectories during venepuncture, taken from video recordings of a skilled practitioner injecting into a practice kit. The framework is also applied to the design and construction of a proposed device for accurate needle guidance during venepuncture administration, assessed as consistent and repeatable in application and does not lead to over puncture. The study provides insights into the ubiquitous peripheral venepuncture process and may contribute to applications in training and in the design of new devices, including for use in robotic automation.

A General Mathematical Framework for Modeling Two-Dimensional Wildland Fire Spread

1995 ◽  
Vol 5 (2) ◽  
pp. 63 ◽  
Author(s):  
GD Richards
Keyword(s):  
Differential Equations ◽  
Wildland Fire ◽  
Fire Spread ◽  
Meteorological Conditions ◽  
Mathematical Framework ◽  
Two Dimensional ◽  
Affecting Factors ◽  
Modelling Framework ◽  
Rate Of Spread ◽  
The Relationship

This work considers the modelling of two dimensional fire spread for heterogeneous fuel and meteorological conditions. Differential equations are used as the modelling form, and a set of partial differential equations that describes fire growth in terms of the rate of spread at each point on the perimeter is derived. These equations require the specification of the rate of spread as a function of the variables affecting it, and form a general modelling framework into which such a function can be placed. To model the relationship between the rate of spread and its affecting factors an analysis of point source ignition fires for homogeneous fuel and meteorological conditions is made. Based on this analysis a spread rate model for heterogeneous conditions is proposed. The resulting differential equations require a sophisticated computer solution, however there are a number of nontrivial fire situations for which solutions can relatively easily be obtained, and example solutions are presented.

scholarly journals A mathematical modelling framework for the regulation of intra-cellular OCT4 in human pluripotent stem cells

PLoS ONE ◽  
2021 ◽  
Vol 16 (8) ◽  
pp. e0254991
Author(s):  
L. E. Wadkin ◽  
S. Orozco-Fuentes ◽  
I. Neganova ◽  
M. Lako ◽  
N. G. Parker ◽  
...  
Keyword(s):  
Stem Cells ◽  
Mathematical Modelling ◽  
Cell Fate ◽  
Pluripotent Stem Cells ◽  
Cell Types ◽  
Human Pluripotent Stem Cells ◽  
Logistic Equation ◽  
Mathematical Framework ◽  
Allee Effects ◽  
Modelling Framework

Human pluripotent stem cells (hPSCs) have the potential to differentiate into all cell types, a property known as pluripotency. A deeper understanding of how pluripotency is regulated is required to assist in controlling pluripotency and differentiation trajectories experimentally. Mathematical modelling provides a non-invasive tool through which to explore, characterise and replicate the regulation of pluripotency and the consequences on cell fate. Here we use experimental data of the expression of the pluripotency transcription factor OCT4 in a growing hPSC colony to develop and evaluate mathematical models for temporal pluripotency regulation. We consider fractional Brownian motion and the stochastic logistic equation and explore the effects of both additive and multiplicative noise. We illustrate the use of time-dependent carrying capacities and the introduction of Allee effects to the stochastic logistic equation to describe cell differentiation. We conclude both methods adequately capture the decline in OCT4 upon differentiation, but the Allee effect model has the advantage of allowing differentiation to occur stochastically in a sub-set of cells. This mathematical framework for describing intra-cellular OCT4 regulation can be extended to other transcription factors and developed into predictive models.

scholarly journals A mathematical framework for modelling the metastatic spread of cancer

2018 ◽  
Author(s):  
Linnéa C Franßen ◽  
Tommaso Lorenzi ◽  
Andrew EF Burgess ◽  
Mark AJ Chaplain
Keyword(s):  
Cancer Cells ◽  
Cancer Cell ◽  
Complex Disease ◽  
Single Cells ◽  
The Body ◽  
Metastatic Spread ◽  
Surrounding Tissue ◽  
Mathematical Framework ◽  
Cell Clusters ◽  
Modelling Framework

AbstractCancer is a complex disease that starts with mutations of key genes in one cell or a small group of cells at a primary site in the body. If these cancer cells continue to grow successfully and, at some later stage, invade the surrounding tissue and acquire a vascular network (tumour-induced angiogenesis), they can spread to distant secondary sites in the body. This process, known as metastatic spread, is responsible for around 90% of deaths from cancer and is one of the so-called hallmarks of cancer.To shed light on the metastatic process, we present a mathematical modelling framework that captures for the first time the interconnected processes of invasion and metastatic spread of individual cancer cells in a spatially explicit manner — a multi-grid, hybrid, individual-based approach. This framework accounts for the spatio-temporal evolution of mesenchymal- and epithelial-like cancer cells, as well as MT1-MMP and MMP-2 dynamics, and interactions with the extracellular matrix.Using computational simulations, we demonstrate that our model captures all the key steps of the invasion-metastasis cascade, i.e. invasion by both heterogeneous cancer cell clusters and by single mesenchymal-like cancer cells; intravasation of these clusters and single cells both via active mechanisms mediated by matrix degrading enzymes (MDEs) and via passive shedding; circulation of cancer cell clusters and single cancer cells in the vasculature with the associated risk of cell death and disaggregation of clusters; extravasation of clusters and single cells; and metastatic growth at distant secondary sites in the body. By faithfully reproducing experimental results, our simulations support the evidence-based hypothesis that the membrane-bound MT1-MMP is the main driver of invasive spread rather than diffusible MDEs like MMP-2.

LPCD framework: Analytical tool or psychological model?

2018 ◽  
Vol 41 ◽  
Author(s):  
David Danks
Keyword(s):  
Decision Making ◽  
Analytical Tool ◽  
Mathematical Framework ◽  
Bayesian Decision ◽  
Perceptual Decision Making ◽  
Psychological Model ◽  
Psychological Reality ◽  
Psychological Theories ◽  
Target Article ◽  
Bayesian Decision Making

AbstractThe target article uses a mathematical framework derived from Bayesian decision making to demonstrate suboptimal decision making but then attributes psychological reality to the framework components. Rahnev & Denison's (R&D) positive proposal thus risks ignoring plausible psychological theories that could implement complex perceptual decision making. We must be careful not to slide from success with an analytical tool to the reality of the tool components.

Reliability of the Conversational Interaction Coding Form When Applied to Natural Conversation of Individuals With Aphasia

2010 ◽  
Vol 20 (4) ◽  
pp. 125-135 ◽  
Author(s):  
Ashley Pozzolo Coote ◽  
Jane Pimentel
Keyword(s):  
Best Practice ◽  
Interobserver Reliability ◽  
Training Session ◽  
Clinical Tool ◽  
Group Setting ◽  
Conversational Interaction ◽  
Video Recordings ◽  
Aphasia Therapy ◽  
Natural Conversation ◽  
Point To Point

Purpose: Development of valid and reliable outcome tools to document social approaches to aphasia therapy and to determine best practice is imperative. The aim of this study is to determine whether the Conversational Interaction Coding Form (CICF; Pimentel & Algeo, 2009) can be applied reliably to the natural conversation of individuals with aphasia in a group setting. Method: Eleven graduate students participated in this study. During a 90-minute training session, participants reviewed and practiced coding with the CICF. Then participants independently completed the CICF using video recordings of individuals with non-fluent and fluent aphasia participating in an aphasia group. Interobserver reliability was computed using matrices representative of the point-to-point agreement or disagreement between each participant's coding and the authors' coding for each measure. Interobserver reliability was defined as 80% or better agreement for each measure. Results: On the whole, the CICF was not applied reliably to the natural conversation of individuals with aphasia in a group setting. Conclusion: In an extensive review of the turns that had high disagreement across participants, the poor reliability was attributed to inadequate rules and definitions and inexperienced coders. Further research is needed to improve the reliability of this potentially useful clinical tool.

A Measurement Modelling Framework for Complex Working Memory Models

2011 ◽  
Author(s):  
Klaus Oberauer ◽  
Jarrold Chris ◽  
Farrell Simon ◽  
Lewandowsky Stephan
Keyword(s):  
Working Memory ◽  
Memory Models ◽  
Modelling Framework ◽  
Working Memory Models

Radioimmunotherapy of Xenografts of Human Pancreatic Carcinomas - Intravenous and Intratumoral Application of 131l-Labelled Monoclonal Antibodies

1986 ◽  
Vol 25 (06) ◽  
pp. 235-238 ◽  
Author(s):  
S. Lander ◽  
M. Bahlo ◽  
R. Montz ◽  
R. Klapdor
Keyword(s):  
Irradiation Dose ◽  
Tumor Regression ◽  
Whole Body ◽  
Inhibit Tumor Growth ◽  
Local Irradiation ◽  
Clinical Value ◽  
Direct Radiation ◽  
Intravenous Injections ◽  
Induce Tumor Regression ◽  
High Doses

The effects of radioimmunotherapy were tested in xenografts of 2 different human pancreatic carcinomas comparing the intravenous and intratumoral application. On principle, intravenous injections of high doses of 131l-anti- Ca 19-9 or -BW 494/32 may inhibit tumor growth. In view of the low direct radiation dose (360-2100 rad), however, other factors than direct toxic effects have to be discussed, e. g. systemic effects due to the high whole-body irradiation. Intratumoral application, however, may induce tumor regression or growth inhibition due to the high local irradiation dose. Consequently, this treatment modality might be of clinical value at least in some patients.

Liquoid Induced Stasis and the Generalized Shwartzman Reaction

1979 ◽  
Vol 41 (04) ◽  
pp. 804-810 ◽  
Author(s):  
Knut Nordstoga
Keyword(s):  
Red Cells ◽  
Renal Lesions ◽  
Intravenous Injections ◽  
Shwartzman Reaction ◽  
Glomerular Capillaries

SummaryThe composition of the occlusive material within dilated glomerular capillaries, following intravenous injections of Liquoid in blue foxes, was studied electron microscopically; it was found that it mainly consisted of a debris in which disintegrated red cells constituted the major component. Damaged platelets and necrotic endothelial remnants were other components. These observations were interpreted as a result of glomerular stasis, and it was concluded that stasis in glomerular capillaries is a basic event in the development of the renal lesions accompanying the generalized Shwartzman reaction.

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