All articles A–Z

Single-atom skeletal editing of arenes

Single-atom skeletal editing of arenes is a set of synthetic organic chemistry methods that change an aromatic ring's framework by inserting, deleting, or exchanging exactly one atom.

Single-atom spintronics

Single-atom spintronics stores bits in the magnetization of individual atoms on surfaces, demonstrated in 2017 by writing and reading single holmium atoms with a scanning tunneling microscope.

Single-atom transistor

A single-atom transistor is a transistor whose active region is a single dopant atom. The first was built with one phosphorus atom in silicon at UNSW in 2012.

Single-balloon enteroscopy

Single-balloon enteroscopy is an endoscopic technique using an overtube with a single balloon to reach the small intestine for biopsy and therapy, mainly for obscure gastrointestinal bleeding.

Single-base extension

Single-base extension, also called minisequencing, is a genotyping method that identifies the base at a known variant site by extending a primer by one labeled nucleotide.

Single-blind study

A single-blind study is a randomized trial design in which participants do not know which treatment they were assigned, while researchers do, reducing biased self-reporting of outcomes.

A single-board computer (SBC) is a complete computer built on a single printed circuit board, integrating processor, memory, and I/O, ranging from hobbyist boards like the Raspberry Pi to industrial embedded controllers.

Single-bullet theory

Single-bullet theory: the Warren Commission's claim that one 6.5-mm bullet (CE 399) caused seven wounds in both Kennedy and Connally on November 22, 1963, underpinning the lone-gunman conclusion and disputed as the 'magic bullet.'

Single-camera setup

Single-camera setup (Ein-Kamera-Verfahren; single-camera mode): film/TV production shooting one setup at a time with one primary camera, contrasting with multi-camera studio work; slower but cinematic, standard for features and single-cam sitcoms.

Single-carrier frequency-domain equalization

Single-carrier frequency-domain equalization (SC-FDE) is a technique that sends data as single-carrier blocks and equalizes them with an FFT, avoiding OFDM's high peak-to-average power ratio.

Single-case experimental design

A single-case experimental design is a psychology and education research method in which one participant or unit is measured repeatedly, providing its own control across baseline and intervention phases.

Single-cell ATAC-seq

Single-cell ATAC-seq (scATAC-seq) is a genomics assay that measures chromatin accessibility genome-wide in individual cells, first reported in 2015 and used to identify cell types and infer transcription-factor activity.

Single-cell ChIP-seq

Single-cell ChIP-seq is a family of genomics methods that profiles histone modifications or transcription factor binding in individual cells, first reported as Drop-ChIP in 2015.

Single-cell mass spectrometry

Single-cell mass spectrometry (SCMS) is a family of analytical techniques that detects and quantifies metabolites, lipids, proteins, and drugs in individual cells rather than in bulk cell populations.

Single-cell protein

Single-cell protein (SCP), also called microbial protein or bioprotein, is protein-rich biomass from bacteria, yeast, fungi, or microalgae grown by fermentation on sugars, gas, or wastewater; 40–80% protein, used as feed and food since Pruteen and Quorn.

Single-cell proteomics

Single-cell proteomics measures the identity and abundance of proteins in individual cells, using mass spectrometry or antibody-based assays; protein abundances span one to ten million copies per cell.

Single-cell RNA sequencing

Single-cell RNA sequencing (scRNA-seq) is a molecular biology method that measures RNA transcript levels in individual cells, revealing the cell types and states in a tissue sample.

Single-cell sequencing

Single-cell sequencing profiles the genome, transcriptome, or epigenome of individual cells (scRNA-seq, scDNA-seq), revealing cell types, dropout and batch-effect artifacts, and powering the Human Cell Atlas.

Single-chain polymer nanoparticles

Single-chain polymer nanoparticles (SCNPs) are nanoparticles formed when a single polymer chain folds onto itself, stabilized by intramolecular cross-links, at sizes of roughly 1.5–20 nm.

Single-Cooper-pair devices

Single-Cooper-pair devices are superconducting circuits that add, remove, or pump charge on an island one Cooper pair, 2e, at a time, exemplified by the Cooper-pair box, the first superconducting qubit to show coherent oscillations, in 1999.

Single-crystal 3D covalent organic frameworks

A single-crystal 3D covalent organic framework (3D COF) is a crystalline porous polymer covalently connected in three dimensions into a defect-poor lattice, first resolved as single crystals in 2013.

Single-crystal cathode material

A single-crystal cathode material is a lithium-ion battery cathode in which each active particle is one continuous crystal, avoiding grain-boundary cracking for longer cycle life and stability.

Single-crystal lithium iron phosphate cathodes

Single-crystal lithium iron phosphate (LiFePO₄, LFP) cathodes are lithium-ion battery cathode materials in which each particle is one continuous olivine crystal, grown as nanoscale plates or rods.

Single-crystal neutron diffraction

Single-crystal neutron diffraction is an analytical technique, first performed by Ernest Wollan at Oak Ridge in 1944, that locates hydrogen atoms and determines complex magnetic structures in crystals.

Single-crystal perovskite

A single-crystal perovskite is a metal halide perovskite semiconductor grown as one continuous lattice without grain boundaries, studied for solar cells with record 25.8% efficiency and for X-ray detectors.

Single-crystal quasi-2D covalent fullerene network

A single-crystal quasi-2D covalent fullerene network is a 2D crystalline material in which C60 molecules are joined by covalent bonds, first synthesized in monolayer form in 2022.

Single-crystal superalloy

A single-crystal superalloy is a nickel-based high-temperature alloy cast so the entire component, typically a gas turbine blade, forms one crystal with no grain boundaries for exceptional creep strength.

Single-crystal-to-single-crystal transformation in MOFs

A single-crystal-to-single-crystal (SCSC) transformation in a metal–organic framework is a solid-state change, triggered by stimuli like solvent exchange, heat, or light, in which the crystal retains crystallinity and can be followed directly by X-ray diffraction.

Single-cylinder engine

A single-cylinder engine is an internal combustion engine with one cylinder and one piston, nicknamed the "thumper" and standard on dirt bikes and small dual-sport motorcycles.