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Differential quadrature phase-shift keying
Differential quadrature phase-shift keying (DQPSK) is a digital modulation scheme encoding two bits per symbol as phase shifts between successive symbols, requiring no reference carrier, used in optical fiber and cellular radio.
Differential reinforcement
Differential reinforcement is a behavior-analytic procedure that reinforces a desired target behavior while withholding reinforcement from competing behaviors, used to reduce problem behaviors; variants include DRA, DRI, DRO, and DRL.
Differential rotation
Differential rotation is when different latitudes of a gaseous body rotate at different speeds, seen in the Sun, where the equator spins in 25 days and the poles in 36.
Differential scanning calorimetry of biomolecules
Differential scanning calorimetry (DSC) of biomolecules measures the heat of protein, nucleic acid, and lipid transitions directly, yielding melting temperature, enthalpy, and full unfolding thermodynamics in a single scan.
Differential scanning fluorimetry
Differential scanning fluorimetry (DSF), also called the thermal shift assay or ThermoFluor, heats a protein while monitoring fluorescence to measure its melting temperature and ligand binding.
Differential scattering cross-section
The differential scattering cross-section, dσ/dΩ, measures how strongly particles scatter into a given solid angle; integrating it over all angles gives the total cross section.
Differential signaling
Differential signaling is an electrical technique that carries information as the voltage difference between a pair of conductors, so noise appearing equally on both wires cancels.
Differential testing
Differential testing is a software testing method that feeds the same inputs to two or more comparable implementations, flagging any disagreement in their results as a possible bug.
Differential thermal analysis
Differential thermal analysis (DTA) is a thermal analysis technique measuring the temperature difference between a sample and an inert reference during controlled heating, detecting transitions without mass change.
Differential topology
Differential topology is the branch of topology studying differentiable manifolds and mappings, using tools like transversality, Morse theory, and bordism, with landmark results including Milnor's 1956 exotic 7-spheres.
Differential-phase-shift quantum key distribution
Differential-phase-shift quantum key distribution (DPS-QKD) is a quantum key distribution protocol proposed by Inoue et al. in 2002 that encodes key bits in the phase difference between consecutive weak coherent pulses.
Differentially closed field
A differentially closed field is a field with a derivation containing enough solutions of differential equations, the differential analog of an algebraically closed field, in a precise first-order sense.
Differentially private learning
Differentially private learning trains machine learning models while mathematically limiting how much any single individual's data can influence the model, by adding calibrated noise during optimization.
Differentially private stochastic gradient descent
Differentially private stochastic gradient descent (DP-SGD) is a training algorithm that clips each example's gradient and adds Gaussian noise, giving deep neural networks a formal differential privacy guarantee.
Differentiated instruction
Differentiated instruction (DI, adaptive teaching) is a pedagogical framework in which teachers adjust content, process, product, and learning environment to students' varied readiness and needs; evidence shows small-to-large but highly context-dependent effects.
Differentiated service delivery (HIV care)
Differentiated service delivery (DSD) is a person-centered approach that adapts HIV services across the care cascade; by 2023, 76% of ART patients in 21 sub-Saharan African countries used it.
Differentiated services
Differentiated services, or Diffserv, is an IETF architecture for scalable quality of service in IP networks, standardized in December 1998 as RFC 2474 and RFC 2475.
Differentiated thyroid carcinoma
Differentiated thyroid carcinoma (DTC), also called differentiated thyroid cancer, is the common, usually curable thyroid cancer group of papillary, follicular, and oncocytic types, over 90% of thyroid cancers, managed by risk-stratified surgery, radioiodine, and thyroglobulin-based follow-up.
Differentiation (economics)
Differentiation in economics is the variation within a product class that makes rival offerings imperfect substitutes for some consumers, restraining price rivalry and supporting higher markups.
Differentiation of T cells
Differentiation of T cells: the process by which thymic progenitors become naive CD4+ and CD8+ T cells and then Th1, Th2, Th9, Th17, Th22, Tfh, Treg, and memory subsets, defined by master transcription factors and effector cytokines.
Differentiation of trigonometric functions
Differentiation of trigonometric functions gives the derivatives of sine, cosine, tangent, cotangent, secant, and cosecant: in radians, differentiating sine gives cosine, and the derivatives cycle back after four steps.
Differentiation rules
Differentiation rules, also called differentiation formulas, are calculus identities that give the derivative of a function built from simpler parts, such as the product, quotient, and chain rules.
Differentiation therapy
Differentiation therapy is a cancer treatment using agents such as retinoic acid to force immature cancer cells to mature instead of killing them, best proven in acute promyelocytic leukemia.
Differentology
"Differentology (Ready for the Road)" is a soca song by Trinidadian artist Bunji Garlin, released in November 2012 and the biggest hit of the 2013 Carnival season.
Difficult People
Difficult People: American dark comedy series (2015–2017) on Hulu, created by and starring Julie Klausner with Billy Eichner as struggling NYC comedians; three seasons, 28 episodes, Amy Poehler executive producer, canceled November 2017.
Difficult to Cure
Difficult to Cure is a 1981 studio album by British hard rock band Rainbow, released on Polydor and the first with American singer Joe Lynn Turner, who replaced Graham Bonnet.
Diffie–Hellman key exchange
Diffie–Hellman key exchange, also called key agreement, is a cryptographic protocol letting two parties establish a shared secret over a public channel, published in 1976.
Difflugia
Difflugia (Leclerc, 1815) is the largest genus of arcellinid testate amoebae, freshwater shelled amoebas building agglutinated tests of mineral particles and diatoms in organic cement; molecular phylogeny shows it is not monophyletic and has been split into Netzelia, Cylindrifflugia, and other genera.
Diffraction
Diffraction is the bending and spreading of waves around an opening or obstacle, exhibited by sound, ocean waves, light, and electron matter waves, strongest when sizes match the wavelength.
Diffraction before destruction
Diffraction before destruction is a principle in X-ray crystallography in which an ultrashort, intensely bright X-ray pulse records the diffraction pattern of a sample before radiation damage destroys it.