Evidence map›Paper›PMID 26054354›Full record

ArticleBMC research notes2015

A parameter estimation method for fluorescence lifetime data.

Daniel Sewell, Hajin Kim, Taekjip Ha, Ping Ma

Abstract read
In one paragraph

Article in BMC research notes, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

4 authors.

Daniel SewellDepartment of Statistics, University of Illinois Urbana-Champaign, 725 S. Wright St., Champaign, IL, 61820, USA. dsewell2@illinois.edu.
Hajin KimSchool of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea. hajin.kim.kr@gmail.com.
Taekjip HaDepartment of Physics, University of Illinois Urbana-Champaign, 1110 W. Green St., 61801, Urbana, IL, USA. tjha@illinois.edu.
Ping MaDepartment of Statistics, University of Georgia, 101 Cedar Street, Athens, GA, 30602, USA. pingma@uga.edu.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundWhen modeling single-molecule fluorescence lifetime experimental data, the analysis often involves fitting a biexponential distribution to binned data. When dealing with small sample sizes, there is the potential for convergence failure in numerical optimization, for convergence to local optima resulting in physically unreasonable parameter estimates, and also for overfitting the data.

resultsTo avoid the problems that arise in small sample sizes, we have developed a gamma conversion method to estimate the lifetime components. The key idea is to use a gamma distribution for initial numerical optimization and then convert the gamma parameters to biexponential ones via moment matching. A simulation study is undertaken with 30 unique configurations of parameter values. We also performed the same analysis on data obtained from a fluorescence lifetime experiment using the fluorophore Cy3. In both the simulation study and the real data analysis, fitting the biexponential directly led to a large number of data sets whose estimates were physically unreasonable, while using the gamma conversion yielded estimates consistently close to the true values.

conclusionsOur analysis shows that using numerical optimization methods to fit the biexponential distribution directly can lead to failure to converge, convergence to physically unreasonable parameter estimates, and overfitting the data. The proposed gamma conversion method avoids these numerical difficulties, yielding better results.

Indexed as

Models, StatisticalPhotonsCarbocyaninesComputer SimulationDNAFluorescenceFluorescent DyesHumansSample SizeSpectrometry, FluorescenceCarbocyaninescyanine dye 3DNAFluorescent Dyes

Identifiers

PMID26054354
PMCPMC4467687

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.