2016 institutional scope statement, definitions and communication/swallowing domains. Cited descriptively, not as a universal licensing rule.

Institutional definitions; citations identify the individual dictionary entry. Direct rendering is limited by the dynamic site; indexed institutional psychology and psychophysiology entries were also consulted.

Robert C. Wilson investigates computational accounts of learning and decision making. His 2019 methods paper with Anne G. E. Collins presents practical ways to test whether a behavioural model and its fitting procedure support the intended scientific inference.^[ref]

A central check is parameter recovery: generate synthetic observations using known settings, then fit the model and compare estimated settings with their known values. Model recovery asks a different question: when synthetic data come from one candidate model, does the comparison procedure select that model over its competitors?^[ref]

For an invented example, a program given data generated with learning rate $\alpha =0.2$ might repeatedly estimate values near $0.8$. That failure could indicate a coding problem, insufficient task information or confounding between parameters. A numerical optimizer returning an answer is therefore not enough to establish a useful psychological measurement. The example illustrates the methodological contribution without assigning an observed human difference to a parameter by name alone.

Anne G. E. Collins studies learning, decision making and executive function using behavioural experiments and computational models. With Robert C. Wilson, she coauthored a 2019 methods paper explaining how to build, simulate, fit and test models of behavior.^[ref]

An illustrative reinforcement learning rule updates a prediction $Q$ after outcome $r$ by $Q_{\mathrm{new}}=Q+\alpha (r-Q)$, where $\alpha$ is a learning rate. Starting at $Q=0.5$ with $r=1$, $\alpha =0.2$ gives $Q_{\mathrm{new}}=0.6$, whereas $\alpha =0.8$ gives $0.9$. This arithmetic shows what a model parameter does; it does not establish that an experimental participant uses that exact rule.

The joint paper emphasizes testing models through computer simulation and parameter recovery, so a fitted parameter is interpreted in light of what the task can actually identify.^[ref]

Institutional research profile: vcresearch.berkeley.edu/faculty/anne-collins .

An operational definition specifies how a variable is measured or manipulated in a particular investigation. Defining stopping performance by a specified stop-signal task, scoring rule and estimation procedure makes the observation reproducible enough to inspect. The broader psychological construct of response inhibition need not be identical to that one procedure.^[ref]

For example, “number of correctly named digits from 1 to 10 under these instructions” operationally defines a numeral identification score. It leaves open whether the same child can compare quantities or count objects. An operational definition makes the measurement concrete; evidence about what that measurement represents is a separate question of construct validity.

A partial report paradigm asks an observer to report a selected subset of presented material. It can estimate available information while reducing the burden of reporting everything. A selection cue before presentation and a cue after presentation test different possibilities: the former can guide initial attention, whereas the latter selects from information that remains available after the display.

George Sperling used brief visual arrays and post-exposure instructions to separate available visual information from whole-report limits. Tone cues could specify a row or reporting order after the symbols disappeared.^[ref]

In an invented three-row display with four symbols per row, suppose the cued row is selected uniformly and an observer correctly reports an average of three symbols from it. Under equal-sampling and accessibility assumptions, the inferred available count across the display is $3\times 3=9$ of the twelve symbols. This is a sampling argument, not an observation of nine simultaneous verbal responses, and the numbers are not Sperling's measured data.

Delaying the selection cue probes changes in availability over time. A declining partial-report advantage can indicate loss of accessible information, but selection, retrieval and output demands must also be considered. The partial report paradigm therefore links perception and sensory memory to experimentally specified responses without equating every report failure with a failure to see.

The visual world paradigm investigates spoken language processing by recording eye tracking while a listener views a scene and hears an utterance. The timing and destinations of fixations provide evidence about which visible referents are being considered during sentence comprehension. The scene can contain real objects or displayed pictures.

In Michael K. Tanenhaus and colleagues' 1995 experiment, a head-mounted tracker recorded eye movements while listeners followed instructions to manipulate real objects. An instruction temporarily allowed a towel phrase to describe either an apple's location or a destination. Comparing scenes with one or two apples changed the referential usefulness of that phrase and affected interpretation.^[ref]

The crucial comparison holds much of the linguistic input constant while manipulating relevant visual context. Fixations require time to plan and execute, so they must be aligned with the utterance and interpreted through the task's alternatives. This makes the paradigm a controlled link between a theory of comprehension and a timed behavioral record.

Mouse tracking records a computer pointer's trajectory over time as a behavioral measure. In psycholinguistics, its Cartesian coordinates can reveal differences between trials that end in the same choice. The trajectory complements final accuracy and reaction time by preserving part of the movement toward the response.

Michael Spivey, Marc Grosjean and Günther Knoblich tested 42 participants with two object pictures in opposite upper corners of a screen. Participants started at the bottom center; a prerecorded word named the target 0.5 seconds after the pictures appeared. A candy distractor shared initial sounds with the target candle, while a jacket provided a dissimilar control. Movements showed greater attraction toward the competing object before reaching the correct target.^[ref]

The authors used linear interpolation to compare trajectories at 101 normalized time positions. That procedure preserves relative movement progression while changing its time scale. Display geometry and movement instructions remain part of the measurement; a curve alone is not a uniquely identified mental state.

A security reduction turns an adversary breaking one stated cryptographic property into an algorithm breaking another property or solving an assumed-hard problem. It specifies the simulation given to the adversary, the relation between success probabilities and the additional computation required. A primitive's hardness assumption can then imply a bound for the constructed scheme.^[ref]

An original reduction illustrates this without a numerical loss. Let a pseudorandom generator expand a uniformly sampled $\lambda$-bit seed $s$ into an $n$-bit string $G(s)$. Consider one-use encryption $c=m\oplus G(s)$ for $n$-bit messages. Suppose adversary $A$ distinguishes which of $m_0,m_1$ was encrypted in the one-challenge cryptographic security game.

Construct a distinguisher $D$ given a string $w$ that is either a generator output or uniformly random. Run $A$ to obtain its message pair, select an independent uniform bit $b$, and give it $c=m_b\oplus w$. Output one exactly when $A$ guesses $b$ correctly. If $w=G(s)$, this is the real encryption experiment. If $w$ is uniform, it is a one-time pad, and the success probability is $1/2$. ThereforeAny nonzero advantage for that encryption game gives the same distinguishing advantage against the generator. The reduction adds the challenge-bit choice, an exclusive or and bookkeeping to the cost of running $A$. It establishes this one-use confidentiality result, without claiming authenticity or safe pad reuse.

Other reductions lose probability or require more computation. For a separate stipulated bound,an adversary with advantage $10^{-3}$, $q=100$ and $\delta =10^{-5}$ implies primitive advantage at least $9.9\times 10^{-6}$. Conversely, a primitive bound $10^{-8}$ at the reduction's actual running time gives only the scheme bound $1.1\times 10^{-5}$. The coefficient and additive term are original illustrative values, not a published bound for a named cipher.

The cryptographic security game and resource accounting remain part of the theorem. A proof cannot transfer a primitive bound stated for a small computation budget to a reduction that exceeds it, or replace the exact scheme's assumptions by a different informal hardness claim.

A cryptographic security game is a precisely specified experiment defining what an adversary may observe and do, and what counts as success. Its rules include key generation, random choices, permitted queries, resource limits and a winning condition. Security statements bound the winning probability or a specified cryptographic distinguishing advantage, often as a function of a cryptographic security parameter. A reduction proves a result about that defined experiment, not every informal meaning of the word secure.^[ref]

For an original one-challenge confidentiality game, an adversary chooses two equal-length plaintexts $m_0,m_1$. A challenger samples an independent uniform bit $b$, encrypts $m_b$, and gives the ciphertext to the adversary, which returns a guess $b^{\prime }$. In this simplified game there are no additional encryption or decryption queries. DefineRandom guessing has advantage zero. A success probability $5/8$ gives advantage $1/8$. Another convention doubles this value; stating the normalization avoids a factor-of-two ambiguity when comparing bounds.

The one-time pad supplies a complete worked example. Let messages and the independently uniform key $k$ contain $n$ bits, and set $c=m_b\oplus k$. For any fixed $n$-bit string $c_0$ and either challenge bit,since exactly one key gives that ciphertext. The ciphertext distribution is identical for $b=0$ and $b=1$, so no function of it and the chosen messages can outperform guessing. The advantage is zero in this game.

Changing the rules can change the result. Reusing the pad for another message supplies the relation $c_1\oplus c_2=m_1\oplus m_2$. A chosen-plaintext attack game grants access to encryptions selected by the adversary; a chosen-ciphertext attack game grants additional decryption access with carefully stated restrictions. The proof for the one-challenge experiment does not establish security under those extra observations.

A forgery game for a message authentication code instead asks for an accepted message/tag pair meeting its freshness condition. That is a different winning event from guessing an encrypted message. The cryptographic security game makes these distinctions inspectable and provides the exact target for a security reduction.

Plasmodium is a genus of unicellular eukaryotic parasites that includes the organisms causing malaria. Its members have a cell nucleus and specialized organelles; they are not bacteria. In the malaria life cycle, multiplication in a vertebrate host alternates with development in a mosquito vector. Different stages occupy different host environments.

Many malaria parasites retain an apicoplast, an organelle descended from a plastid. A blood-stage study connected its essential role to production of isoprenoid precursors: replacing the missing metabolic output could bypass organelle loss in that experimental context. ^[ref] The result concerns a defined life stage and does not imply that every organelle function is dispensable throughout the parasite's life cycle.

A collagen triple helix is a protein structure in which three polypeptide chains wind together into a right-handed superhelix; each individual chain has a left-handed, polyproline-II-like conformation. It is characteristic of collagen and differs from a single alpha helix. The close-packed structure connects protein primary structure to a three-chain assembly: glycine commonly occurs at every third residue in the triple-helical region, conventionally written Gly–X–Y.^[ref][ref]

Glycine's small side group permits close approach near the central axis. Proline and hydroxyproline are frequent at the other positions, while interchain hydrogen bonds and interactions with water help organize the assembly. A model segment with ten Gly–X–Y repeats has 30 residues per chain and 90 across three chains; the three-chain count is distinct from the three-residue sequence period.

The structural picture developed from fiber-diffraction constraints in work by G. N. Ramachandran, G. Kartha and other investigators, rather than from directly seeing every atom in an intact tissue. Later, a synthetic collagen-like peptide provided a sharper test. Its 1994 X-ray crystallography structure, reported at $1.9$ angstrom resolution, confirmed triple-helical packing and interchain bonding. A deliberately introduced glycine-to-alanine substitution caused local untwisting and replaced direct interchain contacts near the substitution with water-mediated bridges.^[ref]

The experiment illustrates why sequence changes can affect a material: even a small side-group change can disturb local packing. The triple-helical molecule is one level of organization; the larger collagen fiber includes additional assembly beyond these three chains.

A protein motif is a recognizable recurring pattern in a protein's sequence or three-dimensional arrangement. A protein sequence motif describes characteristic residues and allowed variation; a protein structural motif describes a recurring spatial combination of structural elements. A motif can be part of a protein domain, without by itself being an independently folding domain or specifying the whole protein's function.

Sequence-pattern notation makes a useful distinction explicit. PROSITE uses defined residues, alternatives and wildcard positions to describe signatures found in protein sequences.^[ref] For an original illustration, take the invented four-position pattern A-x-G-x, with each x allowed any of 20 standard amino acids. It matches $20^2=400$ different residue strings. Finding a match therefore does not uniquely identify a sequence, much less prove a particular biochemical activity. This teaching pattern is not asserted to be a real biological signature.

The EF hand supplies a structural example: two alpha helices flank a loop associated with calcium ion binding in canonical members. Recognizing the arrangement, measuring binding and determining its physiological role are different kinds of evidence.^[ref]

Motifs are useful because local arrangements can recur in proteins with different overall architectures. A sequence signature can guide comparison or experimentation; a structure can test whether the relevant residues approach one another in space. Neither the word “motif” nor a pattern hit alone supplies an affinity measurement or a complete functional annotation.

Protein mass purity is the fraction of the total protein mass in a preparation contributed by the intended protein. With target mass $m_T$ and total protein mass $m_P$, the percentage is $100m_T/m_P$. The denominator includes other proteins, rather than the solvent or the entire mass of the solution.^[ref]

For a constructed preparation containing $0.84\mathrm{mg}$ target protein and $0.16\mathrm{mg}$ other proteins, mass purity is $84\%$. This does not say that $84\%$ of the target molecules are active, nor that $84\%$ of measured catalytic activity comes from them. Those are different quantities from a mass fraction.

An image-based estimate also requires a response model. Suppose densitometry gives target-band intensity 8 and contaminant intensity 2. If both stain equally per unit mass, the inferred purity is $8/(8+2)=80\%$. If, instead, the target signal per mass is twice the contaminant's, the inferred masses are proportional to 4 and 2, giving $4/6\approx 67\%$. These invented response factors illustrate the assumption rather than a measured staining difference.

Thus an SDS-PAGE band pattern supports a mass-purity estimate when identification, detection and calibration are appropriate. Enzymatic purity and specific activity require additional assay information.

Protein kinase C is a family of protein kinases that transfers phosphate from ATP to selected serine residues or threonine residues in target proteins. Conventional members integrate calcium ion and diacylglycerol signals with membrane association, while other family members have different activation requirements. A statement about one isoform should not be assumed to describe every member. ^[ref]

A useful pathway example begins with activation of phospholipase C, which produces diacylglycerol and an inositol-phosphate signal that releases stored calcium ions. These signals can cooperate to recruit and activate a conventional protein kinase C. The downstream phosphorylation then changes target behaviour; a rise in calcium is not itself the phosphorylation reaction. ^[ref]

A pseudokinase is a protein kinase-like protein domain that lacks one or more conserved residues usually important for conventional phosphoryl-transfer catalysis. The term identifies an atypical kinase-like structure and sequence; it does not by itself establish that the domain is biologically useless, unable to bind ATP, or incapable of every catalytic reaction. Such domains can regulate other proteins through binding and conformational effects.^[ref]

A systematic biochemical study used thermal-shift measurements to examine nucleotide and ion binding in thirty-one pseudokinase domains. Binding properties differed: many showed no detectable nucleotide binding, while others bound nucleotides with different requirements for divalent ions. The results challenged the shortcut of assigning the same biochemical behavior to every atypical domain.^[ref]

For an assay example, suppose adding ATP reproducibly changes a purified domain's thermal unfolding curve. That supports an interaction under the assay conditions; it does not yet demonstrate transfer of a phosphate group to a substrate. Conversely, detecting phosphorylation in a protein preparation does not establish which protein catalyzed it: a small contaminating protein kinase can matter. Binding and catalytic assays therefore require different controls.^[ref]

The useful question is what the particular pseudokinase does in its molecular context. Sequence-based expectations guide experiments, but measurements must distinguish nucleotide recognition, chemical turnover and downstream signaling.

An aspartic protease is a protease whose catalytic chemistry depends on aspartic acid side chains. In common examples, their carboxyl groups position and activate a water molecule for peptide bond hydrolysis. Water supplies the attacking nucleophile, unlike a mechanism in which an enzyme side chain itself makes the initial covalent attack.^[ref]

The name concerns catalytic groups, rather than requiring an aspartic-acid residue at every substrate cleavage site. Substrate recognition and catalytic mechanism are distinct properties.

HIV-1 protease provides an experimentally characterized example. In 1989, T. D. Meek and colleagues measured apparent masses of approximately 11,000 under denaturing conditions and 22,000 under nondenaturing conditions; protein cross-linking supplied additional evidence for an active protein dimer. The ratio $22,000/11,000=2$ explains the subunit interpretation.^[ref]

The same study found pH-dependent inactivation consistent with a required unprotonated carboxyl group in the active site. Combining this chemical perturbation with cleavage activity and subunit measurements supported a catalytic classification more specifically than the enzyme's molecular mass alone.^[ref]

Speech intonation is the pattern of pitch variation across an utterance. Its acoustic description commonly uses a pitch contour, tracking the estimated fundamental frequency through voiced portions of speech. The pitch contour describes one component of prosody; it does not by itself encode every distinction conveyed by emphasis, pauses or timing.

To investigate it, record the same phrase with different intended emphasis, then align the recordings by their words and compare the pitch contours. Inspect the underlying waveform as well as the automatic estimate: a tracking error can resemble an abrupt jump. The analysis range matters, and a low pitch floor requires a longer time window, trading the ability to detect low fundamental frequencies against the resolution of rapid changes.^[ref]

An estimated fundamental frequency should not be read as a measured vocal oscillation during a genuinely unvoiced interval. Nor does a rise have a universal meaning independently of the language and conversational setting.

Speech rhythm is the temporal organization of speech: the durations and grouping of segments, syllables, pauses and prominent portions of an utterance. It is one component of prosody, distinct from the changing pitch pattern of speech intonation.

An original measurement exercise is to record several repetitions of a short phrase at a comfortable rate, then again more quickly. Mark the same chosen boundaries on each recording and compare the elapsed times between them. Normalizing an interval by the utterance's total duration distinguishes uniform speeding-up from redistribution of time within the phrase. The result depends on which boundaries were marked, so the annotation rule is part of the measurement method. Software such as Praat stores labelled time intervals in separate annotation tiers, allowing the audio and its proposed segmentation to be inspected together.^[ref]

Perceived rhythmic prominence is not simply the height of the sound pressure waveform. Duration, pitch and intensity can contribute differently, and a claim about regular timing requires measured intervals rather than an impression of a beat.

SLD resolution is a goal-directed inference rule for definite first-order Horn clauses. It selects an atom from the current goal, matches it with a suitably renamed clause head using a most general unifier, and replaces it by that clause's body, applying the same first-order substitution throughout the goal. Reaching the empty goal supplies a successful derivation.^[ref]

For example, the rule ancestor(X,Y) :- parent(X,Y) reduces the query ancestor(ada,Y) to parent(ada,Y). Matching the fact parent(ada,ben) then gives Y=ben. Alternative matching clauses create a search tree. Prolog normally selects the leftmost goal and searches clauses in order with backtracking; a recursive branch can therefore run indefinitely before another branch's valid answer is reached. The logical inference rule and the strategy traversing its alternatives are separate choices.