Uncertainty associated with imperfect knowledge of calibration, efficiency, backgrounds or other persistent model inputs. Repeating the same measurement does not necessarily average it away. Correlated nuisance parameters can propagate it through a likelihood; estimating such an uncertainty is distinct from asserting that the systematic error has a known sign and magnitude.

An early insect embryonic stage with many nuclei sharing cytoplasm before cellularization. Transcriptional patterning can therefore precede formation of individual cell boundaries.

A close biological association on which at least one partner depends for persistence or reproduction under the specified conditions. Obligacy does not itself imply mutual benefit, reciprocity or coevolution.

A root-fungus association with branched fungal exchange structures, arbuscules, within root cortical cells. Nutrient transfer and host carbon allocation are regulated and context-dependent.

A state localized near a crystal surface associated with the termination of bulk bands in a projected gap. A thin film on another metal need not retain the projected gap and localization of its bulk-terminated surface.

An electron state bound outside a conducting surface by image-charge attraction and the surface barrier. Its in-plane effective mass is often close to the free-electron mass and its energy lies below the vacuum level.

A resonant collective electronic response confined to a finite conducting nanostructure. Its near field depends on geometry, environment and loss.

A temporary material supporting another structure during fabrication, then removed selectively. In an oxide-supported polysilicon beam, selective oxide removal makes an air gap while protected substrate contacts retain anchors. Removal must reach beneath the structure without destroying it; a purely vertical etch may not release a lateral overhang.

A broad search over event classes such as jets, leptons and missing transverse momentum, with bins chosen to cover several production or decay possibilities. It still has acceptance and model assumptions; inclusive does not mean sensitive to every supersymmetric spectrum.

A search optimized for a specified production mode and decay topology. Reconstructing a resonance or a kinematic endpoint can reject backgrounds and constrain masses, while making sensitivity depend on branching fractions and intermediate states.

A spectrum with small mass splittings among particles in a decay chain. Small available decay energy makes visible daughters soft, motivating recoil triggers, soft-lepton reconstruction and lifetime-sensitive searches rather than a universal hard-object cut.

Supersymmetry alone does not guarantee stable neutral dark matter. Stability, mass ordering, production history and annihilation dynamics must be specified; conserved R-parity supplies one common stability mechanism.

A three-membered ring containing a positively charged sulfur atom and two carbon atoms. Nucleophilic opening at carbon normally involves backside attack and cleavage of one sulfur–carbon bond.

A four-membered cyclic sulfonium ion containing sulfur and three carbons. A bridged version with equivalent methylene paths can allow nucleophilic opening to restore either configuration at an initially stereogenic carbon.

$\mathrm{C}{\mathrm{H}}_2=\mathrm{CHS}{\mathrm{O}}_2\mathrm{Ph}$, an activated dienophile whose sulfone group can be removed reductively after cycloaddition.

The salt ${\mathrm{Na}}^{+}[{\mathrm{O}}_3\mathrm{S}(\mathrm{C}{\mathrm{H}}_2{)}_4\mathrm{OC}{\mathrm{H}}_2\mathrm{C}{\mathrm{H}}_2\mathrm{C}{\mathrm{H}}_3{]}^{-}$, a product of n-propoxide ring opening of a four-carbon sultone. The ether is at the former oxygen-bound terminal ring carbon.

The ${\mathrm{C}}_6{\mathrm{H}}_{11}-$ group formed by removing one hydrogen from cyclohexane.

A substituent that reduces electron density in a specified molecular region by induction or chemical resonance. The sign and size of its effect depend on connectivity and the measured property.

A substituent that increases electron density in a specified molecular region through induction or chemical resonance. Donation into an arene can affect an attached metal and its other coordination ligands.

Inference of a protein’s three-dimensional structure from information such as sequence, related sequences and known structures. A useful prediction includes an assessment of uncertainty; a confident local fold does not automatically establish a molecular interaction or biological function.