Analyzing 13NN lung washout curves in the presence of intraregional nonuniformities

The use of 13NN and positron imaging provides a powerful noninvasive means of assessing regional pulmonary function. Current techniques for analyzing lung washout curves, however, are subject to error due to intraregional nonuniformities, particularly in the presence of areas with very long time constants or gas trapping. This paper presents a simple “hybrid” method for analyzing 13NN-washout studies that addresses the problems of regions of air trapping and long time constants within a region of interest. This method assumes an exponential washout form for the slow regions, estimates their fractional volume, and subtracts their contribution from the overall washout curve. The modified Stewart-Hamilton method is then applied to the remaining washout curve to calculate its ventilation. The over-all specific ventilation of the region is calculated as the volume-weighted average of the specific ventilations of the two compartments. The performance of the hybrid method is compared with other currently used correction techniques by using a simulated two-compartment lung washout in which there is a variable amount of gas trapping. The analysis techniques are also applied to washout data with intraregional nonuniformities obtained during experimentally created unilateral bronchial obstruction. This new approach has the advantages of automatically correcting for washout truncation, estimating the relative size of the trapped or slow region while eliminating its bias on the regional ventilation, and yet retaining the unrestricted and robust nature of the Stewart-Hamilton method in the analysis of the well-ventilated regions.

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Inter-country inequality as a dynamic process and the problem of post-industrial development

Voprosy Ekonomiki ◽

10.32609/0042-8736-2018-7-5-29 ◽

2018 ◽

pp. 5-29 ◽

Cited By ~ 7

Author(s):

L. M. Grigoryev ◽

V. A. Pavlyushina

Keyword(s):

Economic Growth ◽

Political Institutions ◽

Industrial Development ◽

Modern World ◽

New Approach ◽

Development Level ◽

The World ◽

Long Time ◽

The Difference ◽

Post Industrial

The phenomenon of economic growth is studied by economists and statisticians in various aspects for a long time. Economic theory is devoted to assessing factors of growth in the tradition of R. Solow, R. Barrow, W. Easterly and others. During the last quarter of the century, however, the institutionalists, namely D. North, D. Wallis, B. Weingast as well as D. Acemoglu and J. Robinson, have shown the complexity of the problem of development on the part of socioeconomic and political institutions. As a result, solving the problem of how economic growth affects inequality between countries has proved extremely difficult. The modern world is very diverse in terms of development level, and the article offers a new approach to the formation of the idea of stylized facts using cluster analysis. The existing statistics allows to estimate on a unified basis the level of GDP production by 174 countries of the world for 1992—2016. The article presents a structured picture of the world: the distribution of countries in seven clusters, different in levels of development. During the period under review, there was a strong per capita GDP growth in PPP in the middle of the distribution, poverty in various countries declined markedly. At the same time, in 1992—2016, the difference increased not only between rich and poor groups of countries, but also between clusters.

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Experimental Validation of Minimax Entropy Principle in Ultrasound Images

Recent Advances in Electrical & Electronic Engineering (Formerly Recent Patents on Electrical & Electronic Engineering) ◽

10.2174/2352096511666180912120956 ◽

2019 ◽

Vol 12 (6) ◽

pp. 487-493

Author(s):

Neha Mehta ◽

Svav Prasad ◽

Leena Arya

Keyword(s):

Region Of Interest ◽

Ultrasound Images ◽

Human Gallbladder ◽

New Approach ◽

Non Invasive ◽

Entropy Principle ◽

Significant Performance ◽

Considerable Impact ◽

Ultrasonic Devices ◽

Measure Of Uncertainty

Ultrasound imaging is one of the non-invasive imaging, that diagnoses the disease inside a human body and there are numerous ultrasonic devices being used frequently. Entropy as a well known statistical measure of uncertainty has a considerable impact on the medical images. A procedure for minimizing the entropy with respect to the region of interest is demonstrated. This new approach has shown the experiments using Extracted Region Of Interest Based Sharpened image, called as (EROIS) image based on Minimax entropy principle and various filters. In this turn, the approach also validates the versatility of the entropy concept. Experiments have been performed practically on the real-time ultrasound images collected from ultrasound centers and have shown a significant performance. The present approach has been validated with showing results over ultrasound images of the Human Gallbladder.

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A new approach to the long-time behavior of self-avoiding random walks

Annals of Physics ◽

10.1016/0003-4916(92)90186-p ◽

1992 ◽

Vol 216 (2) ◽

pp. 432

Keyword(s):

Random Walks ◽

Time Behavior ◽

Long Time Behavior ◽

New Approach ◽

Long Time

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Calculating Value Added of Prostitution with Multiple Data: A New Approach for Belgium

Public Finance Review ◽

10.1177/1091142117734173 ◽

2017 ◽

Vol 47 (1) ◽

pp. 58-86 ◽

Cited By ~ 1

Author(s):

Stef Adriaenssens ◽

Jef Hendrickx

Keyword(s):

Sex Workers ◽

Relative Size ◽

Value Added ◽

Added Value ◽

Standard Errors ◽

New Approach ◽

Economic Output ◽

Multiple Data ◽

Innovative Methodology ◽

Starting Point

Economic output implies that underground sectors such as prostitution are taken into account. This article presents an innovative methodology to measure turnover and added value in prostitution based on a combination of observational and Internet data. The method is applied to Belgium. Turnover is broken down in transactions and price per segment. The starting point is an observation-based measure of turnover in one locational and visible segment of the market: window prostitution. Fundamental differences between segments make linear generalizations from one segment invalid. Therefore, we estimate the relative size of transactions in other segments (such as brothels or escort) with Internet data. In combination with measures of average price per transaction, a consolidated estimate of turnover in prostitution in Belgium is measured. Estimates of nonresident production are based on data on sex workers’ country of origin. Several bootstrap replications allow for robustness checks of the delta-based standard errors.

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Enhancement of Region of Interest CT Reconstructions through Multimodal Data

Current Directions in Biomedical Engineering ◽

10.1515/cdbme-2018-0080 ◽

2018 ◽

Vol 4 (1) ◽

pp. 331-335

Author(s):

David Schote ◽

Tim Pfeiffer ◽

Georg Rose

Keyword(s):

Substantial Reduction ◽

Region Of Interest ◽

Proof Of Concept ◽

Multimodal Data ◽

New Approach ◽

Full Field ◽

Lack Of Information ◽

Ct Data ◽

Flight Measurements

AbstractComputed tomography (CT) scans are frequently used intraoperatively, for example to control the positioning of implants during intervention. Often, to provide the required information, a full field of view is unnecessary. I nstead, the region-of-interest (ROI) imaging can be performed, allowing for substantial reduction in the applied X-ray dose. However, ROI imaging leads to data inconsistencies, caused by the truncation of the projections. This lack of information severely impairs the quality of the reconstructed images. This study presents a proof-of-concept for a new approach that combines the incomplete CT data with ultrasound data and time of flight measurements in order to restore some of the lacking information. The routine is evaluated in a simulation study using the original Shepp-Logan phantom in ROI cases with different degrees of truncation. Image quality is assessed by means of normalized root mean square error. The proposed method significantly reduces truncation artifacts in the reconstructions and achieves considerable radiation exposure reductions.

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Inflection point on transpulmonary pressure-volume curves and closing volume

Journal of Applied Physiology ◽

10.1152/jappl.1975.38.2.228 ◽

1975 ◽

Vol 38 (2) ◽

pp. 228-235 ◽

Cited By ~ 23

Author(s):

M. Demedts ◽

J. Clement ◽

D. C. Stanescu ◽

K. P. van de Woestijne

Keyword(s):

Inflection Point ◽

Vital Capacity ◽

Transpulmonary Pressure ◽

Bronchial Obstruction ◽

Closing Volume ◽

Lung Volumes ◽

Nitrogen Washout ◽

Single Breath ◽

Space Effect ◽

Washout Curves

In 20 healthy subjects and 18 patients with bronchial obstruction, closing volume (CV) on single-breath nitrogen washout curves and inflection point (IP) on transpulmonary pressure-volume curves were recorded simultaneously during slow expiratory vital capacity maneuvers. IP and CV did not occur at identical lung volumes, IP being systematically larger than CV for small CV values. This discrepancy could not be attributed to an esophageal or mediastinal artifact. It is suggested that, though CV and IP both express “airway closure,” their sensitivity to closure may differ: CV underestimates closure because of a dead space effect; the latter may vary individually. On the other hand, IP may not reflect the true beginning of closure, particularly when it occurs at higher lung volumes.

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Online Social Gambling and Its Implications for the Study of Marketing Communications

International Journal of Applied Behavioral Economics ◽

10.4018/ijabe.2015070102 ◽

2015 ◽

Vol 4 (3) ◽

pp. 22-50 ◽

Cited By ~ 2

Author(s):

Wilson Ozuem ◽

Jason Prasad

Keyword(s):

Single Case ◽

Internet Technology ◽

Marketing Communication ◽

Single Case Study ◽

New Approach ◽

Real Money ◽

Long Time ◽

Ancient Times ◽

Communication Practices

Gambling has been a part of humanity for a long time, and references to it have been found in some of the earliest dated records. Literature on the topic has been accumulating since ancient times. The advent of Internet technology along with its typical subsets provides a new approach to how gambling is conducted in postmodern times. Drawing on qualitative research and utilising a single case study strategy, this study examines online social gambling and real money gambling marketing communication practices as well as offers some insights into the development and implementation of effective marketing communication programmes. In contrast to existing studies, the paper, in part, proposes integrative and higher levels of marketing communication programmes between online social gambling and real money gambling environments.

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IMPLEMENTASI CONTEXT AWARE PADA SISTEM TRAVEL PLANNER BERBASIS MOBILE

METHOMIKA: Jurnal Manajemen Informatika dan Komputerisasi Akuntansi ◽

10.46880/jmika.vol5no1.pp23-27 ◽

2021 ◽

Vol 5 (1) ◽

pp. 23-27

Author(s):

Viery Darmawan ◽

◽

Rengga Asmara ◽

Ira Prasetyaningrum

Keyword(s):

Contextual Information ◽

The Internet ◽

Context Aware ◽

New Approach ◽

Tourist Attractions ◽

Technological Advances ◽

Long Time ◽

Travel Efficiency ◽

Opening And Closing

In the era of technological advances, tourists will first seek information about the tourist object to be addressed, even tourists often don't have a destination, so they have to search one by one via the internet. In determining travel plans, it is often to see one by one the review of tourist attractions and conclude the results will take a long time, while tourists need actual and fast information to determine the travel plans. In this study, the authors take a new approach, namely by creating a mobile-based travel planner system that compiles travel plans automatically by considering contextual information related to tourist location points, whether of tourist locations during travel days, travel opening and closing hours, so that it will increase travel efficiency without having to do the research manually which takes a long time. The system can also provide travel recommendations based on visitor comments sentiment on Google Places and is equipped with a trip route that will be generated automatically. This research is useful for helping tourists plan their trip actually because of the consideration of contextual information so that it will make it easier and save tourists time.

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