A nitroalkane carbon can join the two ends of a five-carbon conjugated ketone framework. carbon–carbon bond formation, thiolate displacement and nitrite elimination can build a substituted phenol. The nitro-bearing carbon, rather than the nitro nitrogen, enters the aromatic ring.

A Bell basis with phases chosen so that local special-unitary transformations of the two qubits are represented by real four-dimensional rotations. For one standard ordering it is ${\Phi }_{+},i{\Phi }_{-},i{\Psi }_{+},{\Psi }_{-}$. Permuting these vectors changes generator conventions but preserves the invariant concurrence $|{\sum }_j{b}_j^2|$.^[ref]

A carbon substituent opposite the activated N–O leaving group migrates onto nitrogen as the N–O bond cleaves. The oxime geometry therefore determines which bond is replaced by a carbon–nitrogen bond.

Fragmentation of an activated oxime by cleavage of a carbon–carbon bond anti to its N–O leaving group, yielding a nitrile and a carbon electrophile or a product derived from it. Stabilization of a developing carbocation can favour fragmentation over migration. It differs from the usual Beckmann rearrangement, which inserts nitrogen into the migrating carbon–carbon bond and yields an amide after hydrolysis.

In ideal BB84 with uniform independent basis choices, intercepting a fraction $q$ of signals, measuring in a random protocol basis and resending that result introduces sifted-key bit error rate $q/4$. Conditional on a retained position, the attacker chose the wrong basis with probability $1/2$; then the receiver disagrees with the original bit with probability $1/2$. The calculation describes one particular attack and does not establish general security.

A mechanism in which an initial lepton asymmetry is generated and then partly converted into a baryon asymmetry, commonly through electroweak anomalous processes. Heavy Majorana neutrino decays offer one possible realization; a seesaw mechanism by itself does not guarantee the required asymmetry.

Inverse decays or number-violating scatterings can erase an asymmetry after its generation. A viable mechanism must generate a surviving charge combination before the relevant washout processes cease to be effective.

The hydrogen Balmer emission line from the transition between principal quantum numbers three and two. Recombination-line emission from gas photoionized by short-lived massive stars makes it a star-formation tracer, subject to dust attenuation, escape of ionizing photons and contamination by other excitation sources.

A cell that transiently survives a bactericidal antibiotic exposure without necessarily carrying inherited resistance. Its descendants can regain the original susceptibility, connecting physiological state with bacterial persistence rather than a changed growth-inhibition threshold.^[ref]

The periplasm is the compartment between the cytoplasmic and outer membranes in a typical Gram-negative bacterial envelope. Its components and the outer membrane can gate access of external electron acceptors.

Pseudomonas aeruginosa is a bacterium with flexible central carbon metabolism. Its isocitrate branchpoint includes two regulated dehydrogenase routes and a glyoxylate shunt.

Chlamydia trachomatis is an intracellular bacterium that replicates within a modified host-cell inclusion and alternates between infectious and replicative forms.

Rickettsia prowazekii is an intracellular bacterium with extensive biosynthetic losses but retained respiratory and citric-acid-cycle functions. Its cytosolic niche and metabolic inventory differ from those of inclusion-resident Chlamydia.

Chlamydia is a bacterial genus containing intracellular species with developmental transitions between infectious and replicative forms.

Rickettsia parkeri is a spotted-fever-group intracellular bacterium used to study Sca2-dependent actin assembly. Its motility machinery should not be generalized to every rickettsial species.