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Table 1.

Number of lordotic tadpoles in relation to the age at onset of microgravity and the period of μg-exposure during the mission

	SMM-06					Andromède					D-2¹					Andromède					SMM-06²	SMM-06³	SL-J⁴
	STS-84					Soyuz-taxi/ISS					STS-55					Soyuz-taxi/ISS					STS-84	STS-84	STS-47
Year	1997					2001					1993					2001					1997	1997	1994
Stage at launch	25-28					26-27					33-36					45					42-43	25-28	Fertil. in μg
Duration (days)	9					9					10					9					9	9	7
Days of μg	Whole mission					Whole mission					Whole mission					Whole mission					FD5-FD9	FD1-FD5	FD2-FD7
	N	L	N%	N	L	N%	N	L	N%	N	L	N%	N	L	N%	N	L	N%	N	L	N%
First observation	9	25	26.5	14	4	77.8	3	16	15.8	9	3	75.0	15	13	53.6	32	0	100	100
Mean stage	47.1	47.0		46.3	46.0		45.0	44.9		47.0	46.7		47.2	47.0		47.1	−		46
Days after 0g	1-4			2-4			2-6			2-4			1-4			1-4			Post-flight H/O
Second observation	22	7	75.9				3	3	50.0				20	3	87.0	29	0	100
Mean stage	48.3	47.7					46.5	46.0					48.6	47.3		48.5	−
Days after 0g	8-11						9-12						8-11			8-11
Third observation⁵	27	1	96.4										22	1	95.7	29	0	100
Days after 0g	14												14			14

	SMM-06					Andromède					D-2¹					Andromède					SMM-06²	SMM-06³	SL-J⁴
	STS-84					Soyuz-taxi/ISS					STS-55					Soyuz-taxi/ISS					STS-84	STS-84	STS-47
Year	1997					2001					1993					2001					1997	1997	1994
Stage at launch	25-28					26-27					33-36					45					42-43	25-28	Fertil. in μg
Duration (days)	9					9					10					9					9	9	7
Days of μg	Whole mission					Whole mission					Whole mission					Whole mission					FD5-FD9	FD1-FD5	FD2-FD7
	N	L	N%	N	L	N%	N	L	N%	N	L	N%	N	L	N%	N	L	N%	N	L	N%
First observation	9	25	26.5	14	4	77.8	3	16	15.8	9	3	75.0	15	13	53.6	32	0	100	100
Mean stage	47.1	47.0		46.3	46.0		45.0	44.9		47.0	46.7		47.2	47.0		47.1	−		46
Days after 0g	1-4			2-4			2-6			2-4			1-4			1-4			Post-flight H/O
Second observation	22	7	75.9				3	3	50.0				20	3	87.0	29	0	100
Mean stage	48.3	47.7					46.5	46.0					48.6	47.3		48.5	−
Days after 0g	8-11						9-12						8-11			8-11
Third observation⁵	27	1	96.4										22	1	95.7	29	0	100
Days after 0g	14												14			14

FD, flight day; N, normal shape; L, lordotic shape; N%, percentage of normal tadpoles.

¹Data from the rVOR component of the STATEX project; ²after exposure to 1g in the BIORACK centrifuge for 4 days; ³after FD5, exposure to 1g in the BIORACK centrifuge; ⁴fertilization in orbit not before 34 h after launch,stages immediately after handover (H/O) of the samples at the landing day[data from the Japanese Spacelab mission SL-J(Souza et al., 1995)]; ⁵stages were not determined at 14 days after landing.

Lordotic animals were also observed in two other experiments with pre-flight fertilized eggs of Xenopus (stage 25 at launch). One of them was performed on the Russian Cosmos 2229 satellite (11.5-daysμ g), the other on the Japanese Spacelab mission SL-J(STS-47). These experiments are not included in the table because the authors(Snetkova et al., 1995) gave no numbers of lordotic tadpoles. Stages are defined according to published tables (Nieuwkoop and Faber,1967).

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