Aligned contractile muscle strip, as designed, WWD example package

What it describes

A 12 mm skeletal muscle strip held between two attachment loops, specified before it is made. The package carries a design document and nothing else.

A design-only package is complete on its own. Four acceptance criteria are stated, none of them answered.
Four control fields and two response fields sit in the same list with the same shape. The tags separate them.
The validity window makes the specification hold between 168 and 336 hours post seeding, not indefinitely.

Package facts

Every entry, with its manifest role.

ZIP entries
Entry	Bytes	Role	Media type
mimetype	23	(package identity)	text/plain
wwd/manifest.json	482	manifest	application/json
wwd/design.json	7230	design	application/vnd.wwd.design+json

Identity, frame, dimensions and biology.

Aligned contractile muscle strip
Identifier	component/muscle-strip
Kind	contractile_tissue
Dimensions	length 12 mm, width 2 mm, thickness 0.3 mm
Frame	right-handed, axes x y z, units mm, origin centroid of loop-a bore
Validity window	hours_post_seeding 168 to 336
Geometry	not carried in this package

Populations
Role	Cell type	Species	Derivation
primary	skeletal muscle myoblast CL:0000515	Homo sapiens NCBITaxon:9606	primary

Fields
Property	Causal role	Provenance	Value
wwd:ecm_stiffness	control	designed	12 kPa · imposed_by protocol/gel-casting#step-2
wwd:matrix_formulation	control	designed	composition: collagen_i 0.6, fibrin 0.4 · imposed_by protocol/gel-casting#step-1
wwd:seeding_density_volumetric	control	designed	2.0e7 cells/mL · imposed_by protocol/seeding#step-1
wwd:stimulation_frequency	control	designed	1 Hz · imposed_by protocol/maturation#e-stim
wwd:fiber_alignment	response	designed	0.72 1
wwd:peak_twitch_force	response	designed	550 uN

Interfaces
Identifier	Modality	Role
iface/loop-a	mechanical	attachment_loop
iface/loop-b	mechanical	attachment_loop

Measurand, statistic, comparator, limit and method, as written in the design document.

Criteria
Tag	Title	Measurand	Statistic	Limit	Criticality	Axis	Method	n
AC-001	Median twitch force	peak_twitch_force	median	>= 500 uN	critical	response	WWD-TWITCH-001	12
AC-002	Twitch force consistency	peak_twitch_force	cv	<= 0.2 1	major	response	WWD-TWITCH-001	not stated
AC-003	Alignment floor	fiber_alignment	median	>= 0.65 1	major	response	WWD-ALIGN-001	not stated
PC-001	Gel stiffness compliance	ecm_stiffness	value	range 11.0 to 13.0 kPa	major	control	WWD-RHEO-001	not stated