All articles starting with Q
2,252 articles
Quantitative methylation-specific PCR
Quantitative methylation-specific PCR (qMSP) is a PCR method that measures DNA methylation at chosen loci in bisulfite-converted DNA, detecting methylated alleles down to 0.1% for cancer biomarker testing.
Quantitative microscopy
Quantitative microscopy is the family of microscopy techniques that extract numerical measurements of structure, composition, and properties from images, using stereology and image analysis on light and electron micrographs.
Quantitative nanomechanical mapping
Quantitative nanomechanical mapping is an atomic force microscopy technique that maps mechanical properties such as elastic modulus and adhesion by fitting a force-distance curve at every image pixel.
Quantitative NMR
Quantitative NMR (qNMR) is the use of nuclear magnetic resonance spectroscopy to measure concentrations, purities, or composition ratios, used in pharmaceutical analysis, metabolomics, and forensics.
Quantitative oblique back-illumination microscopy
Quantitative oblique back-illumination microscopy (qOBM) is a label-free microscopy technique that measures quantitative phase and refractive index in thick, scattering samples using a bright-field microscope.
Quantitative PCR assay
A quantitative PCR (qPCR) assay measures the amount of a specific DNA or RNA target in a sample, amplifying it while monitoring fluorescence after every cycle.
Quantitative phase imaging
Quantitative phase imaging is a label-free microscopy technique that measures the phase shift of light through transparent specimens, quantifying thickness, refractive index, and dry mass.
Quantitative phase microscopy
Quantitative phase microscopy (QPM) is a label-free microscopy family that measures light's phase delay through transparent specimens to quantify refractive index, thickness, and dry mass.
Quantitative precipitation estimation
Quantitative precipitation estimation (QPE) converts radar, gauge, and satellite observations into precipitation rates and accumulations used in flash flood warning, hydrologic modeling, and data assimilation.
Quantitative precipitation forecast
A quantitative precipitation forecast (QPF) is a forecast of expected rainfall or snowfall, expressed as liquid water depth, over an area during a specific time window.
Quantitative research
Quantitative research collects data in numerical form, such as scores, counts, and ratings, and analyzes it with statistical models using techniques like experiments and surveys.
Quantitative reverse transcription PCR
Quantitative reverse transcription PCR (RT-qPCR) is a molecular biology method that converts RNA to complementary DNA and amplifies it by real-time PCR, quantifying gene expression, microRNAs, and viral load.
Quantitative risk assessment
Quantitative risk assessment, also called quantitative risk analysis or probabilistic risk assessment in the nuclear field, numerically estimates the frequency and extent of harm from an activity against risk criteria.
Quantitative sensory testing
Quantitative sensory testing (QST) is a standardized, non-invasive psychophysical method measuring detection and pain thresholds for thermal, mechanical, and vibratory stimuli to assess sensory nerve function.
Quantitative structure–activity relationship
A quantitative structure–activity relationship (QSAR), also called a quantitative structure–property relationship, is a mathematical model that predicts a chemical's biological or physicochemical activity from its molecular structure, used widely in drug discovery and regulatory chemistry.
Quantitative susceptibility mapping
Quantitative susceptibility mapping (QSM) is an MRI post-processing technique that converts gradient-echo phase images into maps of tissue magnetic susceptibility, quantifying iron, hemorrhage, and calcification.
Quantitative systems pharmacology
Quantitative systems pharmacology (QSP) is a modeling approach coupling mechanistic models of biological systems to pharmacokinetic and pharmacodynamic data to predict drug behavior, optimize dosing, and inform regulatory decisions.
Quantitative trait loci analysis
Quantitative trait loci (QTL) analysis is a genetics method that maps genomic regions associated with variation in measurable traits, reporting LOD scores and effect estimates.
Quantitative trait locus
Quantitative trait locus (QTL): a genetic locus whose alleles affect variation in a quantitative trait such as height or blood pressure. Mapped by linkage or association analysis in F2, RIL, or human populations; distinct from Mendelian loci and molecular eQTLs.
Quantitative trait locus mapping
Quantitative trait locus (QTL) mapping is a statistical genetics method that associates marker variation with quantitative traits to locate genomic regions influencing them, complementary to GWAS.
Quantitative ultrasound
Quantitative ultrasound (QUS) analyzes raw ultrasound echo signals to measure attenuation, backscatter, and speed of sound, quantifying tissue properties for bone, liver fat, and breast cancer assessment.
Quantity
A quantity is an attribute of a phenomenon, body, or substance that can be determined quantitatively, such as length, mass, or electric charge, with values expressed as a number and a unit.
Quantity surveying
Quantity surveying is the construction profession concerned with measuring building work and managing costs, practiced by quantity surveyors on behalf of contractors and building owners.
Quantity surveyor
A quantity surveyor (QS) is a construction professional who manages the costs and contracts of building projects, from feasibility estimates through tendering and construction to the final account.
Quantity theory of money
The quantity theory of money, also called the quantitative theory of money, is an economic theory holding that sustained money growth is the primary cause of sustained inflation.
Quantization (LLM inference)
Quantization in LLM inference maps a model's weights and activations from 16-bit floating point to 8-bit or 4-bit integers, so the model uses less memory and runs faster.
Quantization (machine learning)
Quantization in machine learning represents a neural network's weights, activations, and caches in lower-precision formats such as 8-bit or 4-bit integers, shrinking memory use and speeding up inference.
Quantization (physics)
Quantization in physics is the procedure converting a classical system into a quantum system, and the related fact that energy, charge, and angular momentum take only discrete values.
Quantization (signal processing)
Quantization in signal processing, also called signal quantization, maps a continuous range of amplitudes onto discrete levels; an n-bit converter provides 2^n levels, and the resulting approximation is the source of quantization error and noise.
Quantization-aware large model inference
Quantization-aware large model inference runs large language models with weights at 8-bit or 4-bit precision, cutting memory and cost while keeping accuracy close to full precision.