HolobiomicsLab
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- ▌ Gc Ms Molecular Family Organization 2 · holobiomicslabUse when after auto-deconvolution of GC-MS data has produced a table of individual deconvolved mass spectra (one per detected peak), and your goal is to group spectra into molecular families based on mass spectral similarity rather than retention time or chemical class.
- ▌ Graph Neural Network Encoder Design 2 · holobiomicslabUse when when you need to compare spectrum prediction models fairly across different encoder architectures (GNN vs. FFN vs. Transformer), and you require equivalent settings (same covariates, identical hyperparameter sweeps) to isolate the effect of the encoder design.
- ▌ Hrms Feature Annotation Integration 3 · holobiomicslabUse when you have LC- or GC-HRMS data in mzML format and a feature list (CSV/TSL/Excel) from external feature detection software (e.
- ▌ In Silico Spectrum Generation Cfmid 2 · holobiomicslabUse when when you have a list of SMILES strings representing chemical structures and need to create paired SMILES-spectrum training data for a generative model (like MSGO) without requiring experimental mass spectra.
- ▌ Installation Requirement Validation 2 · holobiomicslabUse when before attempting to run QCxMS2 for the first time, after updating any external dependencies (xtb, CREST, molbar, orca, geodesic_interpolate), or when troubleshooting unexplained calculation failures.
- ▌ Intensity Normalization And Scaling 3 · holobiomicslabUse when when working with raw or filtered MsmsSpectrum objects where peak intensities span a wide dynamic range and need to be normalized for downstream spectrum comparison, database matching, or publication-quality visualization.
- ▌ Intensity Threshold Noise Filtering 3 · holobiomicslabUse when you have loaded a raw or partially processed MsmsSpectrum object and need to reduce spectral noise before annotation, matching, or visualization. Use it especially when spectra contain many weak peaks (e.
- ▌ Isotopologue Pattern Detection Lcms 2 · holobiomicslabUse when after filtering LC-MS features by statistical significance (e.g., p-value < 0.01) and you wish to group features that represent the same metabolite at different isotopologue states.
- ▌ Java Application Build Verification 2 · holobiomicslabUse when when you need to confirm that a Java project's GitHub Actions workflow (e.g., 'dev_build_release.yml') has completed successfully and generated usable build artifacts;
- ▌ Lc Hrms Data Preprocessing Pipeline 3 · holobiomicslabUse when you have raw LC-HRMS metabolomics data in .mzML or .abf format and need to perform peak detection, feature alignment, and metabolite annotation in a reproducible, containerized environment.
- ▌ Singularity Container Backend Setup 3 · holobiomicslabUse when your LC-HRMS metabolomics analysis must run on a high-performance computing cluster (e.g., HiPerGator, SLURM-managed systems) that lacks Docker support or prefers Singularity for security and portability. You have .mzML or .
- ▌ Skyline Import Format Specification 2 · holobiomicslabUse when you have computationally generated precursor m/z values, fragment m/z values, collision energies, and retention time predictions for a set of lipid targets (e.
- ▌ Sparse Distance Matrix Construction 3 · holobiomicslabUse when you have a large collection of MS/MS spectra (hundreds of thousands to millions) that need to be clustered, you have already constructed nearest neighbor indexes on low-dimensional spectrum vectors (via feature hashing), and you need to compute only the relevant pairwise distances between.
- ▌ Spectral Match Result Consolidation 3 · holobiomicslabUse when you have executed batch searches of MS/MS spectra against multiple domain-specific MASST indices and need to integrate the resulting match outputs into a single coherent view.
- ▌ Spectral Quality Control Assessment 2 · holobiomicslabUse when after MS1 extraction (coarse/fine error correction, EIC window extraction) and retention time windowing on a set of mzML files tagged with ionization mode and compound adducts.
- ▌ Transformer Based Fragment Assembly 2 · holobiomicslabUse when when you have CNN-encoded spectral features (¹H and/or ¹³C NMR) and a set of predicted or candidate molecular fragments, and you need to determine which fragments are present and how they connect to form a valid molecular structure.
- ▌ Workflow Architecture Documentation 3 · holobiomicslabUse when you need to understand how a complex MS/MS spectral search system routes query spectra through multiple parallel processing pipelines with different objectives (e.g., reliable exact matching vs. fast approximate matching).
- ▌ Gradient Based Saliency Mapping 3 · holobiomicslabUse when you have a trained graph neural network model for CCS prediction and need to identify which molecular structural features drive individual predictions or systematic biases.
- ▌ Ion Mobility Reference Matching 3 · holobiomicslabUse when you have raw arrival-time data from TWIM-MS and need to convert it to collision cross section (CCS) values for multi-omic analysis.
- ▌ Post Hoc Model Interpretability 3 · holobiomicslabUse when after training a GNN model on molecular structures with continuous targets (e.g., CCS values), when you need to understand which node-level (atom) or edge-level (bond) features contribute most to individual or aggregate predictions.
- ▌ Basepeak Intensity Identification 2 · holobiomicslabUse when when you have Thermo Fisher Scientific .raw files from an Orbitrap instrument and need to identify the m/z value and corresponding intensity of the most abundant ion in each MS1 scan for quality control, method optimization, or feature extraction in a modular R-based proteomics pipeline.
- ▌ C Sharp Wrapper Method Validation 3 · holobiomicslabUse when when integrating an R package that wraps a compiled .NET assembly (such as rawrr), you need to verify that the internal dispatch mechanism between the R layer and the C# layer is operational before attempting to read actual raw data files.
- ▌ Calibration Curve Fitting Ms Data 3 · holobiomicslabUse when you have raw mass spectrometry intensity data from targeted analytes and a set of calibration standard measurements with known concentrations.
- ▌ Chemodiversity Metric Calculation 3 · holobiomicslabUse when when you have sum-normalized peak-abundance matrices from FT-ICR MS data with assigned molecular formulas and need to compare metabolite diversity between treatment groups (e.g., inoculated vs. control samples).
- ▌ Comparative Performance Profiling 2 · holobiomicslabUse when when you have implemented a new or optimized mass spectrometry data processing library and need to demonstrate its computational advantage over established alternatives (e.g., pymzML, pyOpenMS) on real proteomics data. Trigger on availability of: (1) a common input dataset (e.
- ▌ Intensity Drift Artifact Detection 3 · holobiomicslabUse when processing raw MS intensity tables from long measurement sequences where you observe systematic, time-dependent changes in signal magnitude (e.g., progressive increase or decrease in peak intensity across a run).
- ▌ Mass Spectrometry Benchmark Design 3 · holobiomicslabUse when when claiming that one mass spectrometry processing library achieves higher throughput than competitors, or when evaluating whether a new or optimized implementation delivers the expected computational efficiency gains.
- ▌ Metabolite Abundance Normalization 2 · holobiomicslabUse when after loading a raw metabolite abundance table (rows=metabolites, columns=samples) from Metabolomics Workbench format and before mapping metabolites to pathway identifiers or computing enrichment statistics.
- ▌ Ms Quantitative Analysis Standards 3 · holobiomicslabUse when you have raw MS intensity data paired with known-concentration calibration standard measurements, and you need to convert intensities to absolute or relative concentrations.
- ▌ Multi Library Comparative Analysis 3 · holobiomicslabUse when you need to evaluate whether a newly released or candidate library (e.g., spectrum_utils v0.4.
- ▌ Parser Error Reporting Diagnostics 3 · holobiomicslabUse when when implementing or extending a DSL parser (lexer + recursive descent or LALR parser) that accepts user-authored query strings.
- ▌ Pls Pls Da Classification Modeling 2 · holobiomicslabUse when you have a preprocessed peak table (feature matrix with samples × peaks), known sample class labels or group membership, and a goal to classify or discriminate between two or more sample groups.
- ▌ Quantitative Ms Data Preprocessing 3 · holobiomicslabUse when you have raw MS intensity tables showing systematic drift during a measurement sequence (e.g., declining or variable ion counts across a run), particularly in targeted quantification workflows where external calibration standards are available.
- ▌ Storage Origin Metadata Assignment 2 · holobiomicslabUse when when implementing or initializing an MsBackend subclass to handle mass spectrometry data, you must assign dataStorage and dataOrigin variables after loading m/z and intensity values.
- ▌ Encoder Output Dimension Reduction 3 · holobiomicslabUse when you have 512-dimensional representation vectors output from paired ResNet18 encoders processing augmented ion images, and you need to: (1) introduce an intermediate projection space to enable contrastive loss optimization without trivial/collapsed solutions, (2) further compress learned.
- ▌ Mass Spectrometry Peak Enumeration 2 · holobiomicslabUse when you have preprocessed MSI data (peaks already binned and normalized) and need to detect adduct formation patterns across the dataset.
- ▌ Molecular Structure Transformation 2 · holobiomicslabUse when when you have native metabolite structures (SMILES or mol format) and need to predict adduct ions for a mass spectrometry imaging experiment that uses a derivatizing matrix known to produce ions other than common [M+H]+ (positive mode) or [M-H]- (negative mode).
- ▌ Representation Collapse Prevention 3 · holobiomicslabUse when training a contrastive learning model on ion image data (mass spectrometry imaging) where augmented pairs of the same ion image must maximize similarity while different images minimize similarity.
- ▌ Chromatographic Peak Shape Comparison 2 · holobiomicslabUse when after retention-time-based and abundance-correlation-based feature grouping have produced composite feature groups, and you need to identify which features within a group actually represent different compounds.
- ▌ Extracted Ion Chromatogram Inspection 2 · holobiomicslabUse when after running tardisPeaks() in screening mode or peak detection mode, when you need to visually confirm that target compounds are visible in the expected m/z and retention time windows, verify that peak integration boundaries are correct, diagnose whether sawtooth artefacts are present.
- ▌ Isotope Pattern And Adduct Assignment 2 · holobiomicslabUse when after feature detection has produced a TSV feature table (from Asari or equivalent) containing m/z, retention time, and intensity columns, and before MS1 or MS2 annotation.
- ▌ Motif Similarity Ranking Interpretation 2 · holobiomicslabUse when after executing MassQL queries against a MotifDB reference database and retrieving ranked motif matches, when you need to determine which database entries represent true structural correspondence versus spurious matches, and to decide whether a motif's top-ranking hit is sufficiently.
- ▌ S4 Class Definition And Slot Management 2 · holobiomicslabUse when you are extending the MsBackend virtual class to create a new backend for storing MS spectra data and need to define the internal data structure. Specifically: when you have multiple types of spectra variables (e.
- ▌ Structural Cluster Network Construction 2 · holobiomicslabUse when after you have identified statistically significant LC-MS features and run MamsiStructSearch to generate structural clusters (isotopologue groups, adduct groups, cross-assay links) and computed correlation cluster assignments.
- ▌ Candidate Metadata Record Serialization 3 · holobiomicslabUse when after computing InChIKey and neighbourhood scores for library match candidates, you need to write results to a persistent format (CSV, JSON, or database) for storage, sharing, and interpretation.
- ▌ Chromatographic Modality Classification 3 · holobiomicslabUse when when ingesting raw or vendor-format mass spectrometry data files of unknown or mixed acquisition modality, and you need to automatically determine whether the input originated from liquid chromatography (LC), gas chromatography (GC), ion mobility spectrometry (IMS), or MS imaging (e.
- ▌ Cross Language Interface Implementation 2 · holobiomicslabUse when you have a mature R analysis pipeline (e.g., using Spectra objects for MS data) but need access to specialized algorithms or calculations available only in Python libraries (e.g., CosineGreedy similarity from matchms).
- ▌ Dense Neural Network Layer Construction 3 · holobiomicslabUse when when you have a binned MS/MS spectrum vector (e.g., 9948-dimensional input from 10,000 equally-spaced m/z bins in the 10–1000 Da range) and need to compress it into a learned latent representation (e.
- ▌ Hypergeometric Distribution Calculation 2 · holobiomicslabUse when when you have raw strain correlation scores (or similar overlap-based metrics) computed across genomic cluster family (GCF) and molecular family (MF) pairs of varying sizes, and you need to make those scores comparable across links with different GCF sizes (#G), MF sizes (#m), and.
- ▌ Interactive Plot Construction Mass Spec 2 · holobiomicslabUse when after LC-MS data has been converted to mzML format and processed through peak detection (e.g., MS-DIAL output) to yield a feature table with internal standard identifications, retention times, m/z values, and intensity measurements across multiple samples.
- ▌ Mass Spectrometry Structural Annotation 3 · holobiomicslabUse when after identifying statistically significant features (e.
- ▌ Mass Spectrometry Tolerance Calibration 3 · holobiomicslabUse when after generating a feature table from mzML data (via Asari) and before performing MS1 or MS2 annotation.
- ▌ Mass Spectrum Extraction And Formatting 4 · holobiomicslabUse when you have raw GC-MS data in netCDF or vendor-specific binary format and need to separate co-eluting compounds and extract clean mass spectra for each individual chemical component prior to molecular networking, spectral matching, or metabolite identification workflows.
- ▌ Ms Signal Correction Strategy Selection 2 · holobiomicslabUse when you have loaded raw MS intensity tables into QuantyFey and observe or suspect intensity drift artifacts across your measurement sequence. Drift is especially likely in long-running targeted MS experiments where calibration curves or internal standards show systematic variation over time.
- ▌ Natural Product Classifier Substitution 2 · holobiomicslabUse when gNPS has ceased supplying ClassyFire ontology information for spectral library matches, causing downstream ConCISE consensus classification to fail or produce incomplete ontology fields.
- ▌ Natural Products Workflow Orchestration 3 · holobiomicslabUse when you have LC-MS/MS DDA metabolomics data (positive and/or negative ionization modes) and sample metadata (originating taxon) for one or more samples, and you need to generate a Wikidata-connected RDF knowledge graph for integrated natural products analysis, taxonomy-aware compound.
- ▌ Pathway Database Filtering By Detection 2 · holobiomicslabUse when you have run a metabolomics experiment with incomplete coverage of a reference pathway database (e.g., 10–100% of database metabolites detected), and you plan to use ORA for pathway enrichment. The skill is essential if your detection method has known sensitivity limits (e.
- ▌ M Z Value Ordering Enforcement 2 · holobiomicslabUse when when implementing or modifying data replacement methods (e.g., `mz<-`, `peaksData<-`) in a writable MsBackend subclass, or when accepting user-supplied m/z vectors destined for storage in a Spectra backend.
- ▌ Mass Fragment Pattern Querying 3 · holobiomicslabUse when after LDA modeling has produced an inferred motifset (JSON format) containing Mass2Motifs with fragment and neutral-loss patterns.
- ▌ Mass Spectrum Peak Aggregation 2 · holobiomicslabUse when you have a processed mass spectrum object with assigned molecular formulas for individual peaks and need to summarize peaks by their heteroatom composition—e.
- ▌ Ms Data Constraint Enforcement 3 · holobiomicslabUse when implementing or validating a new MsBackend class that stores m/z and intensity values, or when assigning peak data to an existing backend. Triggers include: (1) implementing a replacement method (e.g., mz<- or intensity<-) for a backend class;
- ▌ Mzml File Format Understanding 2 · holobiomicslabUse when you have mass spectrometry raw data in mzML format (including compressed variants like mzML.
- ▌ Neural Network Model Inference 2 · holobiomicslabUse when you have pre-trained MSGO model weights (PFAS or lipid variant) and a set of experimental mass spectra (either from reference evaluation sets or real wastewater/environmental samples) in CSV format with m/z and intensity pairs, and you need to obtain candidate molecular structures ranked.
- ▌ Peak Validation Synthetic Data 2 · holobiomicslabUse when after running a 1D peak detection function (e.g., mzapy.peaks.find_peaks_1d_localmax or mzapy.peaks.find_peaks_1d_gauss) on synthetic mass spectra with known peak locations and heights.
- ▌ R Internal Function Invocation 3 · holobiomicslabUse when when you need to verify or retrieve package-internal metadata about compiled .NET assembly location and version before processing raw mass spectrometry files, or when testing the R↔C# dispatch mechanism in isolation without loading actual Orbitrap .raw data files.
- ▌ Spectral Data Table Conversion 3 · holobiomicslabUse when when you have mzPeak format spectrum files and need to work with spectrum metadata, intensity/m/z arrays, or precursor information in a tabular, columnar, or vectorized computing environment.
- ▌ Time Domain Signal Apodization 3 · holobiomicslabUse when working with raw FT-ICR transient data (e.g., ESI_NEG_SRFA.d format) prior to noise thresholding and mass-domain calibration.
- ▌ Java Build Artifact Validation 3 · holobiomicslabUse when when you need to verify that a Java project's automated build pipeline (GitHub Actions workflow) executes without errors and generates distributable artifacts (e.g., .deb installers, portable binaries, or .jar files).
- ▌ Matplotlib Figure Customization 2 · holobiomicslabUse when when rendering spectrum data (m/z vs. intensity arrays) from MZA files and need to control visual presentation: applying m/z range windows, setting line colors and labels for legend identification, sizing the figure, or choosing between interactive display versus file export.
- ▌ Metabolic Marker Identification 2 · holobiomicslabUse when after batch effect removal and sample integration, when you have a normalized feature-by-sample abundance matrix (finalData) with corresponding sample group labels (finalLabel), and need to identify which metabolites discriminate between biological conditions or phenotypes for focused.
- ▌ Peak Height Threshold Selection 2 · holobiomicslabUse when when applying iterative peak detection (local-maximum or Gaussian-fit methods) to 1D extracted ion chromatograms (XICs), arrival time distributions (ATDs), or MS1 spectra from MZA-format files, and you need to decide which peaks to retain based on their intensity.
- ▌ Python Filter Class Inheritance 2 · holobiomicslabUse when you need to filter compounds during Pickaxe network expansion based on domain-specific criteria (e.g., mass matching, similarity thresholds, retention time windows) that are not covered by built-in filters.
- ▌ Spectral Data Format Validation 3 · holobiomicslabUse when after converting existing mass spectrometry formats (mzML, vendor formats) into mzPeak using command-line tools or when receiving mzPeak files from external sources.
- ▌ Adduct Mass Difference Matching 3 · holobiomicslabUse when you have computed a histogram of pairwise mass differences from MS imaging data and need to (1) identify which observed mass differences correspond to biologically relevant or chemically known adducts, or (2) rank the most frequently observed mass differences to discover dominant adduct.
- ▌ Imzml Continuous Format Parsing 2 · holobiomicslabUse when you have acquired raw mass spectrometry imaging data in imzML continuous format (e.g., from CardinalIO or other MSI instruments) and need to load it into R as a structured MSImagingExperiment object to perform statistical analysis, normalization, or visualization.
- ▌ Mzml To Imzml Format Conversion 2 · holobiomicslabUse when you have mzML files generated from raw vendor mass spectrometry imaging data and need to create imzML output compatible with software like Cardinal MSI, METASPACE, M2aia, or SCiLS Lab.
- ▌ Raw Vendor File Format Handling 2 · holobiomicslabUse when you have collected imaging mass spectrometry data in vendor-specific raw format (.raw files from Bruker, Waters, Thermo, or other instrument manufacturers) and need to convert it to the open, vendor-agnostic mzML XML format before downstream imzML construction and spatial alignment.
- ▌ Background Ion Contaminant Removal 2 · holobiomicslabUse when you have a feature table from LC-MS data alongside blank (solvent-only) sample runs, and you want to remove features whose intensity in study samples is not substantially higher than their intensity in blanks.
- ▌ Dropout Regularization Application 2 · holobiomicslabUse when when training a deep neural network on mass spectrometry spectral data where overfitting is a risk (especially with data augmentation applied), and when you need both regularization during training AND uncertainty quantification at inference time via multiple forward passes with dropout.
- ▌ Feature Table Row Count Validation 3 · holobiomicslabUse when after peak quality filtering has been applied to a composite map peak detection output using SNR (>2), goodness-of-fit (peakshape > 0.5), minimum peak height (default 1e5), and prominence (≥20% of peak_height) thresholds.
- ▌ Formula Accuracy Metric Evaluation 2 · holobiomicslabUse when when training or validating a deep learning model for molecular formula prediction from tandem MS/MS spectra, use this metric to track whether the model's predicted formula (including hydrogen atoms) exactly matches the annotated ground-truth formula.
- ▌ Lipid Library Format Specification 2 · holobiomicslabUse when when you have curated or synthesized a set of custom lipid species (e.g., rare or organism-specific lipids, modified lipids, or synthetic standards) and need to integrate them into LipidMatch for candidate matching against your experimental MS/MS datasets.
- ▌ Metabolite Set Decomposition Plage 3 · holobiomicslabUse when you have peak intensity data from metabolomics experiments with annotated metabolites assigned to known groupings (KEGG pathways, Reactome, GNPS Molecular Families, or MS2LDA Mass2Motifs) and need to identify which metabolite sets change significantly across experimental comparisons while.
- ▌ Metabolomics Data Input Validation 2 · holobiomicslabUse when when importing a tab-delimited or Sciex OS text export metabolomics dataset into mzQuality, before building the SummarizedExperiment object.
- ▌ Adduct Mass Calculation From Smiles 2 · holobiomicslabUse when when you have a metabolite SMILES structure and need to predict which adduct ions will appear in a mass spectrum acquired with a chemical derivatizing matrix.
- ▌ Adduct Mass Offset Parameterization 2 · holobiomicslabUse when when processing LC-MS metabolomics feature tables where adduct annotation is absent or incomplete, and you need to identify which ionization adducts are present in your mass spectrometry data.
- ▌ Batch Aware Normalization Workflows 2 · holobiomicslabUse when your LC-MS feature table exhibits intensity variations across samples that correlate with technical batches (e.
- ▌ Binary And XML Data Deserialization 2 · holobiomicslabUse when you have raw LC-MS data in .mzML (XML-based) or Thermo .raw (proprietary binary) format and need to load it into memory for visualization, querying, or downstream analysis.
- ▌ Chemical Class Metadata Integration 2 · holobiomicslabUse when you have generated a GNPS molecular network (classical or feature-based workflow) and possess chemical class annotations (from GNPS library matching, ClassyFire, or other structural classifiers) that you wish to propagate onto network nodes and edges to enable chemical family-level.
- ▌ Chemical Match Score Interpretation 3 · holobiomicslabUse when when you have query chemicals identified by GC-MS (with Match.Factor values) and need to verify structural similarity against a reference chemical library to confirm compound identity or detect structural analogs (e.g., isomers or homologs).
- ▌ Classification Metric Visualization 2 · holobiomicslabUse when after training or evaluating a classification model (e.g., a Siamese neural network for spectrum similarity prediction) and obtaining a prediction array and corresponding ground-truth label array.
- ▌ Collision Cross Section Calculation 2 · holobiomicslabUse when you have raw or processed arrival-time data from a traveling-wave ion mobility mass spectrometry (TWIM-MS) platform and need to convert it into standardized collision cross section (CCS) values for comparative analysis across samples or datasets.
- ▌ CSV Format Specification Compliance 2 · holobiomicslabUse when after feature extraction or feature alignment when you have FeatureSet or Sample objects that must be exported as CSV files for sharing, archival, or downstream analysis. Specifically: (1) when exporting single-sample feature tables from find_feature() output;
- ▌ Cytoscape Edge Node File Formatting 2 · holobiomicslabUse when after computing pairwise mass-difference transformations between FT-ICR MS peaks and matching them to a reference biochemical transformation key, you have putative edge data (source peak, target peak, transformation type, mass error) and node data (peaks with m/z, molecular formula.
- ▌ Dataset Preprocessing And Filtering 3 · holobiomicslabUse when when you have a raw GNPS or other spectral library dataset with inconsistent or incomplete instrument annotations, and you need to verify or reproduce reported dataset split counts (e.g., training/test compound ratios). Apply this skill when an instrument allowlist fix (e.
- ▌ De Novo Structure Candidate Ranking 3 · holobiomicslabUse when when you have high-resolution LC-MS/MS data for an unknown metabolite or small molecule, have computed or measured the molecular ion mass and fragmentation spectrum, and require de-novo structure generation because the compound is absent from spectral libraries or structure databases.
- ▌ Eic Similarity Correlation Analysis 4 · holobiomicslabUse when after abundance-correlation-based feature group refinement when you observe that larger feature groups (particularly those with 3+ features in the same m/z–retention-time window) may contain features with different peak shapes or retention-time shifts in their EICs, or when abundance.
- ▌ Feature Intensity Ratio Calculation 2 · holobiomicslabUse when after generating a feature table from LC-MS/MS data when your experiment includes blank control samples and you need to remove features driven by background ions or instrumental contamination.
- ▌ Fixed Architecture Layer Validation 3 · holobiomicslabUse when after loading a specXplore session data object file from the hard drive and instantiating a dashboard session layer with it, validate that the architecture layer has initialized without errors and that the interactive dashboard is responsive to user input.
- ▌ Flux Propensity Dataset Integration 2 · holobiomicslabUse when when you have (1) LC-MS normalized intracellular metabolite abundance data across multiple cell lines or samples, (2) a constraint-based metabolic model with stoichiometric coefficients, and (3) a need to quantify metabolic control through substrate availability independently of enzymatic.