Raw band intensities from two zymography gels are not automatically on one numerical scale. Gel composition, development, staining, imaging and exposure can change the response of an entire gel. A shared reference lane can help align gels, while a loading control addresses a different question within samples. Keeping those two normalisations separate prevents a technical scale difference from becoming a biological claim.
This guide develops a focused reader question within the Zymography subject guide. It adds a complete mechanism, original worked decisions, changed-context transfer checks and explicit limits. Read it with The Gold Standard of Education | Learning That Transfers into Life and the How X Works.
All numerical examples are invented teaching cases. They are not measurements of a real deposit, assay, service or fermentation process.
In the fictional example, gel A has corrected sample signal 600 and reference signal 800 arbitrary units; gel B has corrected sample signal 350 and reference signal 400. Raw samples appear lower on B, because 350 is below 600. Relative to each gel’s shared reference, A is 600/800 = 0.75 and B is 350/400 = 0.875, so the ranking reverses. This ratio is useful only if the same reference material, band identity, linear response range and processing rule apply. A functional zymography methods article explains normalising replicate gels to a chosen band; Makowski and Ramsby's calibrator study evaluated gelatinase standards for calibration; and Raykin and colleagues showed how same-gel total-protein detection can improve loading normalisation over a stated range. These sources support distinct control jobs rather than a universal conversion between arbitrary gels.
Continue with the Zymography subject guide, Enzymology, Zymogens and Experimental Design.
The short answer is to keep the target quantity, observation and reporting rule separate. Name what the system intends to estimate, what was actually observed, how the summary was formed and which conditions make the inference defensible. If one field is missing, keep the ambiguity visible.
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Keep background correction, shared-reference scaling, sample loading, response range, band identity and biological replication distinct.
ROUTE 1 · CHAPTERS 1–6
Define the scale problem
Separate raw signal, correction, reference purpose and the worked reversal.
ROUTE 2 · CHAPTERS 7–12
Control the assay
Protect loading, band identity, processing, calibration form and reference stability.
ROUTE 3 · CHAPTERS 13–18
Preserve evidence
Keep paired ratios, replication, saturation, uncertainty and connected designs visible.
ROUTE 4 · CHAPTERS 19–22
Audit and continue
Transfer to another gel, repair overclaims and follow verified assay routes.
Chapter contents
Define the scale problem · Chapters 1–6
1. Define the cross-gel comparison
2. Separate raw image signal from biological activity
3. Distinguish background correction from normalisation
4. Assign the shared reference lane one job
Control the assay · Chapters 7–12
7. Keep sample-loading normalisation separate
8. Use the same band identity on every gel
9. Preserve development and imaging conditions
10. Avoid forcing a zero-intercept calibration
Preserve evidence · Chapters 13–18
13. Do not average ratios before checking denominators
14. Preserve biological and technical replication
15. Test whether one gel is saturated
16. Carry reference uncertainty into the comparison
Audit and continue · Chapters 19–22
20. Repair the claim that a darker band means more activity
State whether the goal is comparing two biological samples run on different gels, combining a series across days or estimating a response relative to a calibrator. The design must connect the gels before the final analysis tries to do so.
Write the evidence as a ledger: target quantity, population, unit, sampling or measurement rule, reported value and decision limit. Mark each input as observed, stipulated, fitted or assumed so a change of basis cannot hide inside the arithmetic.
Apply the rule to the central fictional case, keep unrounded inputs and label the result with its population and protocol. Then name one plausible alternative explanation and the observation that would distinguish it.
For Zymography, complete seven fields: target question, object or population, unit, boundary, protocol, result and decision limit. For ‘define the cross-gel comparison’, a plausible number can otherwise hide a changed condition or undocumented selection step.
Change one condition that matters while holding the remaining basis fixed. Recalculate or re-inspect the evidence, say what stays comparable and name the stronger conclusion that still does not follow.
Close with two lines. The first states what the evidence establishes under the named conditions. The second states the nearest tempting conclusion that remains unsupported. Ask another reader to identify the condition that would make the first line false.
CHAPTER 2 OF 22 · Define the scale problem
2. Separate raw image signal from biological activity
Densitometry produces an image-derived signal under a declared sign and background rule. It can support a relative assay statement without becoming an absolute enzyme amount or net activity inside intact tissue.
Draw the mechanism before interpreting the number. Put selection, measurement, transformation and reporting in order. Then name one rival explanation and the additional observation that would distinguish it.
Apply the rule to the central fictional case, keep unrounded inputs and label the result with its population and protocol. Then name one plausible alternative explanation and the observation that would distinguish it.
For Zymography, complete seven fields: target question, object or population, unit, boundary, protocol, result and decision limit. For ‘separate raw image signal from biological activity’, a plausible number can otherwise hide a changed condition or undocumented selection step.
Change one condition that matters while holding the remaining basis fixed. Recalculate or re-inspect the evidence, say what stays comparable and name the stronger conclusion that still does not follow.
Close with two lines. The first states what the evidence establishes under the named conditions. The second states the nearest tempting conclusion that remains unsupported. Ask another reader to identify the condition that would make the first line false.
CHAPTER 3 OF 22 · Define the scale problem
3. Distinguish background correction from normalisation
Subtracting local background addresses staining or image baseline within a region. Dividing by a shared reference aligns a gel-level scale. Dividing by loaded protein addresses sample input. These operations solve different problems.
Use two checks that fail differently. Reconstruct a total from its parts, test a limiting case, inspect a shared control or repeat the result from definitions. Agreement is useful only when both checks do not reuse the same hidden assumption.
Apply the rule to the central fictional case, keep unrounded inputs and label the result with its population and protocol. Then name one plausible alternative explanation and the observation that would distinguish it.
For Zymography, complete seven fields: target question, object or population, unit, boundary, protocol, result and decision limit. For ‘distinguish background correction from normalisation’, a plausible number can otherwise hide a changed condition or undocumented selection step.
Change one condition that matters while holding the remaining basis fixed. Recalculate or re-inspect the evidence, say what stays comparable and name the stronger conclusion that still does not follow.
Close with two lines. The first states what the evidence establishes under the named conditions. The second states the nearest tempting conclusion that remains unsupported. Ask another reader to identify the condition that would make the first line false.
CHAPTER 4 OF 22 · Define the scale problem
4. Assign the shared reference lane one job
Place the same characterised reference material on each gel under a predeclared lane and band rule. Its job is to connect scales. It does not prove sample identity or correct an unsuitable substrate.
Keep the comparison fair. Hold the population, interval, protocol and unit constant before assigning a difference to the mechanism of interest. A changed condition creates a changed comparison even when a column heading stays the same.
Apply the rule to the central fictional case, keep unrounded inputs and label the result with its population and protocol. Then name one plausible alternative explanation and the observation that would distinguish it.
For Zymography, complete seven fields: target question, object or population, unit, boundary, protocol, result and decision limit. For ‘assign the shared reference lane one job’, a plausible number can otherwise hide a changed condition or undocumented selection step.
Change one condition that matters while holding the remaining basis fixed. Recalculate or re-inspect the evidence, say what stays comparable and name the stronger conclusion that still does not follow.
Close with two lines. The first states what the evidence establishes under the named conditions. The second states the nearest tempting conclusion that remains unsupported. Ask another reader to identify the condition that would make the first line false.
A calibrator must respond in a range where its relation to signal is sufficiently supported. A very dark reference near saturation and a barely detected reference near the noise floor cannot anchor a reliable ratio simply because both have numbers.
Separate measurement from decision. A value can be correctly calculated yet too local, uncertain or method-dependent for the intended action. Report the value with its conditions and say what evidence a stronger decision would require.
Apply the rule to the central fictional case, keep unrounded inputs and label the result with its population and protocol. Then name one plausible alternative explanation and the observation that would distinguish it.
For Zymography, complete seven fields: target question, object or population, unit, boundary, protocol, result and decision limit. For ‘check the calibrator response range’, a plausible number can otherwise hide a changed condition or undocumented selection step.
Change one condition that matters while holding the remaining basis fixed. Recalculate or re-inspect the evidence, say what stays comparable and name the stronger conclusion that still does not follow.
Close with two lines. The first states what the evidence establishes under the named conditions. The second states the nearest tempting conclusion that remains unsupported. Ask another reader to identify the condition that would make the first line false.
Gel A sample/reference is 600/800 = 0.75. Gel B sample/reference is 350/400 = 0.875. Raw intensity ranks A above B; connected ratios rank B above A. The reversal reveals why raw cross-gel comparison is unsafe.
| Gel | Corrected sample | Corrected reference | Sample/reference |
|---|---|---|---|
| A | 600 | 800 | 0.750 |
| B | 350 | 400 | 0.875 |
Preserve identity and order. Equal totals can hide different mechanisms when records come from different strata, gels, booking classes, vessels or time windows. Keep those identities until the reader’s question no longer depends on them.
Apply the rule to the central fictional case, keep unrounded inputs and label the result with its population and protocol. Then name one plausible alternative explanation and the observation that would distinguish it.
For Zymography, complete seven fields: target question, object or population, unit, boundary, protocol, result and decision limit. For ‘work the 600 versus 350 reversal’, a plausible number can otherwise hide a changed condition or undocumented selection step.
Change one condition that matters while holding the remaining basis fixed. Recalculate or re-inspect the evidence, say what stays comparable and name the stronger conclusion that still does not follow.
Close with two lines. The first states what the evidence establishes under the named conditions. The second states the nearest tempting conclusion that remains unsupported. Ask another reader to identify the condition that would make the first line false.
If gel A received 10 micrograms of sample protein and gel B 5, a per-input calculation answers another question. Do not divide by both reference and input without stating why each denominator belongs in the model.
Test a deliberately changed case. Change one assumption while holding the remaining basis fixed, calculate again and explain why the result moves or stays stable. Transfer is demonstrated when the reasoning survives the new context.
Apply the rule to the central fictional case, keep unrounded inputs and label the result with its population and protocol. Then name one plausible alternative explanation and the observation that would distinguish it.
For Zymography, complete seven fields: target question, object or population, unit, boundary, protocol, result and decision limit. For ‘keep sample-loading normalisation separate’, a plausible number can otherwise hide a changed condition or undocumented selection step.
Change one condition that matters while holding the remaining basis fixed. Recalculate or re-inspect the evidence, say what stays comparable and name the stronger conclusion that still does not follow.
Close with two lines. The first states what the evidence establishes under the named conditions. The second states the nearest tempting conclusion that remains unsupported. Ask another reader to identify the condition that would make the first line false.
The reference band and sample band must represent the intended comparable activity region. A band at similar apparent mass is not automatically the same protein, and a shifted or overlapping band may need another identity rule.
State the boundary of inference beside the answer. Name the system, representation and interval to which the result applies, then name the nearest tempting claim that the evidence does not establish.
Apply the rule to the central fictional case, keep unrounded inputs and label the result with its population and protocol. Then name one plausible alternative explanation and the observation that would distinguish it.
For Zymography, complete seven fields: target question, object or population, unit, boundary, protocol, result and decision limit. For ‘use the same band identity on every gel’, a plausible number can otherwise hide a changed condition or undocumented selection step.
Change one condition that matters while holding the remaining basis fixed. Recalculate or re-inspect the evidence, say what stays comparable and name the stronger conclusion that still does not follow.
Close with two lines. The first states what the evidence establishes under the named conditions. The second states the nearest tempting conclusion that remains unsupported. Ask another reader to identify the condition that would make the first line false.
Incubation time, temperature, substrate, renaturation, staining, scanner settings and file handling can affect the response. A shared reference can absorb some multiplicative gel variation; it cannot justify uncontrolled changes of mechanism.
Use uncertainty as structure. Vary the input most capable of changing the conclusion over a defensible range and show whether the ranking or decision changes. One linked sensitivity check is more useful than a generic caveat list.
Apply the rule to the central fictional case, keep unrounded inputs and label the result with its population and protocol. Then name one plausible alternative explanation and the observation that would distinguish it.
For Zymography, complete seven fields: target question, object or population, unit, boundary, protocol, result and decision limit. For ‘preserve development and imaging conditions’, a plausible number can otherwise hide a changed condition or undocumented selection step.
Change one condition that matters while holding the remaining basis fixed. Recalculate or re-inspect the evidence, say what stays comparable and name the stronger conclusion that still does not follow.
Close with two lines. The first states what the evidence establishes under the named conditions. The second states the nearest tempting conclusion that remains unsupported. Ask another reader to identify the condition that would make the first line false.
CHAPTER 10 OF 22 · Control the assay
10. Avoid forcing a zero-intercept calibration
If background-subtracted signal follows signal = a + b×amount over the supported range, dividing by one reference assumes the intercept is negligible or otherwise handled. Check blanks and a calibration curve before imposing proportionality.
Finish with an evidence package: source records, definitions, exclusions, sample or instrument identity, calculations, validation result and decision rule. A later reader should be able to reproduce the result and see what would cause revision.
Apply the rule to the central fictional case, keep unrounded inputs and label the result with its population and protocol. Then name one plausible alternative explanation and the observation that would distinguish it.
For Zymography, complete seven fields: target question, object or population, unit, boundary, protocol, result and decision limit. For ‘avoid forcing a zero-intercept calibration’, a plausible number can otherwise hide a changed condition or undocumented selection step.
Change one condition that matters while holding the remaining basis fixed. Recalculate or re-inspect the evidence, say what stays comparable and name the stronger conclusion that still does not follow.
Close with two lines. The first states what the evidence establishes under the named conditions. The second states the nearest tempting conclusion that remains unsupported. Ask another reader to identify the condition that would make the first line false.
Suppose the same reference decreases steadily across gels. That pattern may reflect reference degradation, assay drift or storage change. Normalising every sample by a failing reference can create an artificial rise.
Write the evidence as a ledger: target quantity, population, unit, sampling or measurement rule, reported value and decision limit. Mark each input as observed, stipulated, fitted or assumed so a change of basis cannot hide inside the arithmetic.
Apply the rule to the central fictional case, keep unrounded inputs and label the result with its population and protocol. Then name one plausible alternative explanation and the observation that would distinguish it.
For Zymography, complete seven fields: target question, object or population, unit, boundary, protocol, result and decision limit. For ‘handle a drifting reference lane’, a plausible number can otherwise hide a changed condition or undocumented selection step.
Change one condition that matters while holding the remaining basis fixed. Recalculate or re-inspect the evidence, say what stays comparable and name the stronger conclusion that still does not follow.
Close with two lines. The first states what the evidence establishes under the named conditions. The second states the nearest tempting conclusion that remains unsupported. Ask another reader to identify the condition that would make the first line false.
Low, medium and high reference levels can reveal nonlinearity and place samples within range. Use a fitted curve only when its model and residuals support the interpolation; do not extrapolate beyond the standards.
Draw the mechanism before interpreting the number. Put selection, measurement, transformation and reporting in order. Then name one rival explanation and the additional observation that would distinguish it.
Apply the rule to the central fictional case, keep unrounded inputs and label the result with its population and protocol. Then name one plausible alternative explanation and the observation that would distinguish it.
For Zymography, complete seven fields: target question, object or population, unit, boundary, protocol, result and decision limit. For ‘use several reference levels when needed’, a plausible number can otherwise hide a changed condition or undocumented selection step.
Change one condition that matters while holding the remaining basis fixed. Recalculate or re-inspect the evidence, say what stays comparable and name the stronger conclusion that still does not follow.
Close with two lines. The first states what the evidence establishes under the named conditions. The second states the nearest tempting conclusion that remains unsupported. Ask another reader to identify the condition that would make the first line false.
CHAPTER 13 OF 22 · Preserve evidence
13. Do not average ratios before checking denominators
The mean of sample/reference ratios is generally different from mean sample divided by mean reference. Preserve gel pairing because each numerator belongs with its own gel-level denominator.
Use two checks that fail differently. Reconstruct a total from its parts, test a limiting case, inspect a shared control or repeat the result from definitions. Agreement is useful only when both checks do not reuse the same hidden assumption.
Apply the rule to the central fictional case, keep unrounded inputs and label the result with its population and protocol. Then name one plausible alternative explanation and the observation that would distinguish it.
For Zymography, complete seven fields: target question, object or population, unit, boundary, protocol, result and decision limit. For ‘do not average ratios before checking denominators’, a plausible number can otherwise hide a changed condition or undocumented selection step.
Change one condition that matters while holding the remaining basis fixed. Recalculate or re-inspect the evidence, say what stays comparable and name the stronger conclusion that still does not follow.
Close with two lines. The first states what the evidence establishes under the named conditions. The second states the nearest tempting conclusion that remains unsupported. Ask another reader to identify the condition that would make the first line false.
CHAPTER 14 OF 22 · Preserve evidence
14. Preserve biological and technical replication
Repeated scans of one lane, duplicate lanes of one aliquot and independently prepared biological samples occupy different levels. A cross-gel analysis should preserve which variation belongs to imaging, assay and biology.
Keep the comparison fair. Hold the population, interval, protocol and unit constant before assigning a difference to the mechanism of interest. A changed condition creates a changed comparison even when a column heading stays the same.
Apply the rule to the central fictional case, keep unrounded inputs and label the result with its population and protocol. Then name one plausible alternative explanation and the observation that would distinguish it.
For Zymography, complete seven fields: target question, object or population, unit, boundary, protocol, result and decision limit. For ‘preserve biological and technical replication’, a plausible number can otherwise hide a changed condition or undocumented selection step.
Change one condition that matters while holding the remaining basis fixed. Recalculate or re-inspect the evidence, say what stays comparable and name the stronger conclusion that still does not follow.
Close with two lines. The first states what the evidence establishes under the named conditions. The second states the nearest tempting conclusion that remains unsupported. Ask another reader to identify the condition that would make the first line false.
Imagine gel C sample 950 and reference 1000 on a scanner capped at 1023. Both signals are near the ceiling. Their ratio 0.95 can conceal severe compression; dilution or another qualified exposure is needed to test the range.
Separate measurement from decision. A value can be correctly calculated yet too local, uncertain or method-dependent for the intended action. Report the value with its conditions and say what evidence a stronger decision would require.
Apply the rule to the central fictional case, keep unrounded inputs and label the result with its population and protocol. Then name one plausible alternative explanation and the observation that would distinguish it.
For Zymography, complete seven fields: target question, object or population, unit, boundary, protocol, result and decision limit. For ‘test whether one gel is saturated’, a plausible number can otherwise hide a changed condition or undocumented selection step.
Change one condition that matters while holding the remaining basis fixed. Recalculate or re-inspect the evidence, say what stays comparable and name the stronger conclusion that still does not follow.
Close with two lines. The first states what the evidence establishes under the named conditions. The second states the nearest tempting conclusion that remains unsupported. Ask another reader to identify the condition that would make the first line false.
CHAPTER 16 OF 22 · Preserve evidence
16. Carry reference uncertainty into the comparison
If reference A is 800±40 and B is 400±30, the normalised comparison inherits denominator uncertainty. Sensitivity or an appropriate model should show whether B still ranks above A across plausible values.
Preserve identity and order. Equal totals can hide different mechanisms when records come from different strata, gels, booking classes, vessels or time windows. Keep those identities until the reader’s question no longer depends on them.
Apply the rule to the central fictional case, keep unrounded inputs and label the result with its population and protocol. Then name one plausible alternative explanation and the observation that would distinguish it.
For Zymography, complete seven fields: target question, object or population, unit, boundary, protocol, result and decision limit. For ‘carry reference uncertainty into the comparison’, a plausible number can otherwise hide a changed condition or undocumented selection step.
Change one condition that matters while holding the remaining basis fixed. Recalculate or re-inspect the evidence, say what stays comparable and name the stronger conclusion that still does not follow.
Close with two lines. The first states what the evidence establishes under the named conditions. The second states the nearest tempting conclusion that remains unsupported. Ask another reader to identify the condition that would make the first line false.
CHAPTER 17 OF 22 · Preserve evidence
17. Compare batches through a connected design
A connected design places common pooled references or bridge samples across batches and distributes biological groups across gels. Running every control on one gel and every treatment on another leaves group and batch confounded.
Test a deliberately changed case. Change one assumption while holding the remaining basis fixed, calculate again and explain why the result moves or stays stable. Transfer is demonstrated when the reasoning survives the new context.
Apply the rule to the central fictional case, keep unrounded inputs and label the result with its population and protocol. Then name one plausible alternative explanation and the observation that would distinguish it.
For Zymography, complete seven fields: target question, object or population, unit, boundary, protocol, result and decision limit. For ‘compare batches through a connected design’, a plausible number can otherwise hide a changed condition or undocumented selection step.
Change one condition that matters while holding the remaining basis fixed. Recalculate or re-inspect the evidence, say what stays comparable and name the stronger conclusion that still does not follow.
Close with two lines. The first states what the evidence establishes under the named conditions. The second states the nearest tempting conclusion that remains unsupported. Ask another reader to identify the condition that would make the first line false.
CHAPTER 18 OF 22 · Preserve evidence
18. Recognise what a shared reference cannot repair
A shared reference cannot restore an omitted biological replicate, identify an unknown band, reverse selective sample degradation or prove physiological activity. It aligns a supported analytical scale and nothing more.
State the boundary of inference beside the answer. Name the system, representation and interval to which the result applies, then name the nearest tempting claim that the evidence does not establish.
Apply the rule to the central fictional case, keep unrounded inputs and label the result with its population and protocol. Then name one plausible alternative explanation and the observation that would distinguish it.
For Zymography, complete seven fields: target question, object or population, unit, boundary, protocol, result and decision limit. For ‘recognise what a shared reference cannot repair’, a plausible number can otherwise hide a changed condition or undocumented selection step.
Change one condition that matters while holding the remaining basis fixed. Recalculate or re-inspect the evidence, say what stays comparable and name the stronger conclusion that still does not follow.
Close with two lines. The first states what the evidence establishes under the named conditions. The second states the nearest tempting conclusion that remains unsupported. Ask another reader to identify the condition that would make the first line false.
For gel C with sample 510 and reference 600 in the supported range, the ratio is 0.85. It falls between A and B. The placement is defensible only because the same reference identity and processing rules connect all three.
Use uncertainty as structure. Vary the input most capable of changing the conclusion over a defensible range and show whether the ranking or decision changes. One linked sensitivity check is more useful than a generic caveat list.
Apply the rule to the central fictional case, keep unrounded inputs and label the result with its population and protocol. Then name one plausible alternative explanation and the observation that would distinguish it.
For Zymography, complete seven fields: target question, object or population, unit, boundary, protocol, result and decision limit. For ‘transfer to a third gel’, a plausible number can otherwise hide a changed condition or undocumented selection step.
Change one condition that matters while holding the remaining basis fixed. Recalculate or re-inspect the evidence, say what stays comparable and name the stronger conclusion that still does not follow.
Close with two lines. The first states what the evidence establishes under the named conditions. The second states the nearest tempting conclusion that remains unsupported. Ask another reader to identify the condition that would make the first line false.
CHAPTER 20 OF 22 · Audit and continue
20. Repair the claim that a darker band means more activity
Replace ‘gel A has more enzyme because 600 exceeds 350’ with ‘raw signals are on different gel scales; relative to the common reference, A is 0.75 and B is 0.875 under the validated response range’. Keep the biological interpretation bounded.
Finish with an evidence package: source records, definitions, exclusions, sample or instrument identity, calculations, validation result and decision rule. A later reader should be able to reproduce the result and see what would cause revision.
Apply the rule to the central fictional case, keep unrounded inputs and label the result with its population and protocol. Then name one plausible alternative explanation and the observation that would distinguish it.
For Zymography, complete seven fields: target question, object or population, unit, boundary, protocol, result and decision limit. For ‘repair the claim that a darker band means more activity’, a plausible number can otherwise hide a changed condition or undocumented selection step.
Change one condition that matters while holding the remaining basis fixed. Recalculate or re-inspect the evidence, say what stays comparable and name the stronger conclusion that still does not follow.
Close with two lines. The first states what the evidence establishes under the named conditions. The second states the nearest tempting conclusion that remains unsupported. Ask another reader to identify the condition that would make the first line false.
Is a housekeeping protein automatically a zymography loading control? No. The control must match the sample, assay and intended denominator.
Can one reference lane correct saturation? No. Saturated signals have lost proportional information.
Should ratios from different gels be pooled immediately? Only after checking reference stability, range, pairing and the experimental-unit structure.
Write the evidence as a ledger: target quantity, population, unit, sampling or measurement rule, reported value and decision limit. Mark each input as observed, stipulated, fitted or assumed so a change of basis cannot hide inside the arithmetic.
Apply the rule to the central fictional case, keep unrounded inputs and label the result with its population and protocol. Then name one plausible alternative explanation and the observation that would distinguish it.
For Zymography, complete seven fields: target question, object or population, unit, boundary, protocol, result and decision limit. For ‘answer focused reader questions’, a plausible number can otherwise hide a changed condition or undocumented selection step.
Change one condition that matters while holding the remaining basis fixed. Recalculate or re-inspect the evidence, say what stays comparable and name the stronger conclusion that still does not follow.
Close with two lines. The first states what the evidence establishes under the named conditions. The second states the nearest tempting conclusion that remains unsupported. Ask another reader to identify the condition that would make the first line false.
Use the primary calibration and normalisation studies for method context, then follow Enzymology, Zymogens and Experimental Design for molecular identity, latent activity and replication.
Draw the mechanism before interpreting the number. Put selection, measurement, transformation and reporting in order. Then name one rival explanation and the additional observation that would distinguish it.
Apply the rule to the central fictional case, keep unrounded inputs and label the result with its population and protocol. Then name one plausible alternative explanation and the observation that would distinguish it.
For Zymography, complete seven fields: target question, object or population, unit, boundary, protocol, result and decision limit. For ‘continue through verified assay routes’, a plausible number can otherwise hide a changed condition or undocumented selection step.
Change one condition that matters while holding the remaining basis fixed. Recalculate or re-inspect the evidence, say what stays comparable and name the stronger conclusion that still does not follow.
Close with two lines. The first states what the evidence establishes under the named conditions. The second states the nearest tempting conclusion that remains unsupported. Ask another reader to identify the condition that would make the first line false.