Timothy Andersen

Dr. Timothy Andersen


Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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22 April 2021 in Nature Communications
Verified
Journal Article
Open access
PDF file
GDGeorge D. Dickinson
George D. Dickinson
GMGolam Md Mortuza
Golam Md Mortuza
WCWilliam Clay
William Clay
LPLuca Piantanida
Luca Piantanida
CGChristopher M. Green
Christopher M. Green
WHWilliam L. Hughes
William L. Hughes
DNA is a compelling alternative to non-volatile information storage technologies due to its information density, stability, and energy efficiency. Previous studies have used artificially synthesized DNA to store data and automated next-generation sequencing to read it back. Here, we report digital Nucleic Acid Memory (dNAM) for applications that require a limited amount of data to have high information density, redundancy, and copy number. In dNAM, data is encoded by selecting combinations of single-stranded DNA with (1) or without (0) docking-site domains. When self-assembled with scaffold DNA, staple strands form DNA origami breadboards. Information encoded into the breadboards is read by monitoring the binding of fluorescent imager probes using DNA-PAINT super-resolution microscopy. To enhance data retention, a multi-layer error correction scheme that combines fountain and bi-level parity codes is used. As a prototype, fifteen origami encoded with ‘Data is in our DNA!\n’ are analyzed. Each origami encodes unique data-droplet, index, orientation, and error-correction information. The error-correction algorithms fully recover the message when individual docking sites, or entire origami, are missing. Unlike other approaches to DNA-based data storage, reading dNAM does not require sequencing. As such, it offers an additional path to explore the advantages and disadvantages of DNA as an emerging memory material.

3 January 2024 in Foods
Verified
Journal Article
Open access
PDF file
HBHabeeb Abolaji Babatunde
Habeeb Abolaji Babatunde
JCJoseph Collins
Joseph Collins
RLRianat Lukman
Rianat Lukman
RSRose Saxton
Rose Saxton
TATimothy Andersen
Timothy Andersen
Owen M. McdougalOwen M. Mcdougal
Owen M. Mcdougal
Protein content variation in milk can impact the quality and consistency of dairy products, necessitating access to in-line real time monitoring. Here, we present a chemometric approach for the qualitative and quantitative monitoring of β-lactoglobulin and α-lactalbumin, using mid-infrared spectroscopy (MIR). In this study, we employed Hotelling T2 and Q-residual for outlier detection, automated preprocessing using nippy, conducted wavenumber selection with genetic algorithms, and evaluated four chemometric models, including partial least squares, support vector regression (SVR), ridge, and logistic regression to accurately predict the concentrations of β-lactoglobulin and α-lactalbumin in milk. For the quantitative analysis of these two whey proteins, SVR performed the best to interpret protein concentration from 197 MIR spectra originating from 42 Cornell University samples of preserved pasteurized modified milk. The R2 values obtained for β-lactoglobulin and α-lactalbumin using leave one out cross-validation (LOOCV) are 92.8% and 92.7%, respectively, which is the highest correlation reported to date. Our approach introduced a combination of preprocessing automation, genetic algorithm-based wavenumber selection, and used Optuna to optimize the framework for tuning hyperparameters of the chemometric models, resulting in the best chemometric analysis of MIR data to quantitate β-lactoglobulin and α-lactalbumin to date.

27 August 2025 in Foods
Verified
Journal Article
Open access
PDF file
HBHabeeb Abolaji Babatunde
Habeeb Abolaji Babatunde
Owen M. McdougalOwen M. Mcdougal
Owen M. Mcdougal
TATimothy Andersen
Timothy Andersen
The preprocessing of infrared spectra can significantly improve predictive accuracy for protein, carbohydrate, lipid, or other nutrition components, yet optimal preprocessing selection is typically empirical, tedious, and dataset specific. This study introduces a Bayesian optimization-based framework designed for the automated selection of optimal spectral preprocessing pipelines within a chemometric modeling context. The framework was applied to mid-infrared spectra of milk to predict compositional parameters for fat, protein, lactose, and total solids. A total of 385 averaged spectra corresponding to 198 unique samples was split into a 70/30 ratio (training/test) using a group-aware Kennard-Stone algorithm, resulting in 269 averaged spectra (135 unique samples) for training and 116 spectra (58 unique samples) for testing. Six regression models: Elastic Net, Gradient Boosting Machines (GBM), Partial Least Squares (PLS), RidgeCV Regression, LassoLarsCV, and Support Vector Regression (SVR) were evaluated across three preprocessing conditions: (1) no preprocessing, (2) literature-derived custom preprocessing (e.g., MSC, SNV, and first and second derivatives), and (3) optimized preprocessing via the proposed Bayesian framework. Optimized preprocessing consistently outperformed other methods, with RidgeCV achieving the best performance for all components except lactose, where PLS slightly outperformed it. Improvements in predictive accuracy, particularly in terms of RMSEP were observed across all milk components. The best RMSEP results were achieved for protein (RMSEP = 0.054, R2=0.981) and lactose (RMSEP = 0.026, R2=0.917), followed by fat (RMSEP = 0.139, R2=0.926) and total solids (RMSEP = 0.154, R2=0.960). Literature-based pipelines demonstrated inconsistent effectiveness, highlighting the limitations of transferring preprocessing methods between datasets. The Bayesian optimization approach identified relatively simple yet highly effective preprocessing pipelines, typically involving few steps. By eliminating manual trial and error, this data-driven strategy offers a robust and generalizable solution that streamlines spectral modeling in dairy analysis and can be readily applied to other types of spectroscopic data across various domains.

16 April 2018 in BMC Bioinformatics
Verified
Journal Article
Open access
PDF file
MKMatthew D. King
Matthew D. King
TLThomas Long
Thomas Long
DPDaniel L. Pfalmer
Daniel L. Pfalmer
TATimothy Andersen
Timothy Andersen
Owen M. McdougalOwen M. Mcdougal
Owen M. Mcdougal
Conventional de novo drug design is costly and time consuming, making it accessible to only the best resourced research organizations. An emergent approach to new drug development is drug repurposing, in which compounds that have already gone through some level of clinical testing are examined for efficacy against diseases divergent than their original application. Repurposing of existing drugs circumvents the time and considerable cost of early stages of drug development, and can be accelerated by using software to screen existing chemical databases to identify suitable drug candidates. Small-molecule Peptide-Influenced Drug Repurposing (SPIDR) was developed to identify small molecule drugs that target a specific receptor by exploring the conformational binding space of peptide ligands. SPIDR was tested using the potent and selective 16-amino acid peptide α-conotoxin MII ligand and the α3β2-nicotinic acetylcholine receptor (nAChR) isoform. SPIDR incorporates a genetic algorithm-based, heuristic search procedure, which was used to explore the ligand binding domain of the α3β2-nAChR isoform using a library consisting of 640,000 α-conotoxin MII peptide analogs. The peptides that exhibited the highest affinity for α3β2-nAChR were used as models for a small-molecule structure similarity search of the PubChem Compound database. SPIDR incorporates the SimSearcher utility, which generates shape distribution signatures of molecules and employs multi-level K-means clustering to insure fast database queries. SPIDR identified non-peptide drugs with estimated binding affinities nearly double that of the native α-conotoxin MII peptide. SPIDR has been generalized and integrated into DockoMatic v 2.1. This software contains an intuitive graphical interface for peptide mutant screening workflow and facilitates mapping, clustering, and searching of local molecular databases, making DockoMatic a valuable tool for researchers in drug design and repurposing.

21 April 2023 in BMC Bioinformatics
Verified
Journal Article
Open access
PDF file
GMGolam Md Mortuza
Golam Md Mortuza
JGJorge Guerrero
Jorge Guerrero
SLShoshanna Llewellyn
Shoshanna Llewellyn
MTMichael D. Tobiason
Michael D. Tobiason
GDGeorge D. Dickinson
George D. Dickinson
TATimothy Andersen
Timothy Andersen
Deoxyribonucleic acid (DNA) is emerging as an alternative archival memory technology. Recent advancements in DNA synthesis and sequencing have both increased the capacity and decreased the cost of storing information in de novo synthesized DNA pools. In this survey, we review methods for translating digital data to and/or from DNA molecules. An emphasis is placed on methods which have been validated by storing and retrieving real-world data via in-vitro experiments.

1 April 2017
Verified
Conference Paper
Closed access
KSKelsey Suyehira
Kelsey Suyehira
SLSimon Llewellyn
Simon Llewellyn
RZReza M. Zadegan
Reza M. Zadegan
WHWilliam L. Hughes
William L. Hughes
TATimothy Andersen
Timothy Andersen
The global demand for digital data is projected to be greater than the supply of semiconductor grade silicon in 2040 [1]. When combined with the need to archive information [2], nucleic acids are being explored as an alternative memory material [1-7]. According to a recent study, the information density of nucleic acid memory (NAM) is one thousand times greater than flash memory and has the ability to last for hundreds of years [1]. Presented here is an algorithm for converting digital data into unique DNA sequences for glacial storage. Biologically inspired, our coding scheme maps hexadecimal characters to sequences of three DNA nucleotides. This mapping avoids repeating sequences and start codons, which could have adverse effects. We were able to encode and decode various file types without error.