Abstract

Cotton plants were grown hydroponically with controlled environment. Third, growth chamber grown true leaves of cotton plants were tagged on the day they became macroscopically visible. Beginning 3.0 days after tagging, five leaf harvests representing maturity dates were made at successive 2- or 3-day intervals. Measurements with a spectrophotometer made on the leaves showed that the largest increase in reflectance, about 5%, and decrease in transmittance, about 8%, occurred between average values for after-tagging-ages of 3.5 days and 8.0 days over the 0.75–1.35-μ wavelength interval. Between after-tagging-ages of 3.5 days and 8.0 days, leaves expanded approximately fivefold, numbers of intercellular spaces approximately doubled, and thicknesses increased 14%. The theory of diffuse reflectance and transmittance of a compact leaf of equivalent water thickness (EWT) specified by D is generalized to include also the noncompact leaf characterized by many intercellular air spaces, can be regarded as a pile of N compact layers separated by infinitesimal air spaces. The void area index (VAI) of a noncompact leaf is given by N − 1, where N is not necessarily an integer. Predictions from the generalized theory include a measure of the water, air, and plant pigments in a leaf. An effective dispersion curve associated with the leaf surfaces is also obtained. A derived parameter D/N largely determines the reflectance and transmittance of a typical leaf over the 1.40–2.50-μ spectral range. A cotton leaf is highly compact when it first unfolds. At this point D/N ~ 180 μ. This value is essentially the leaf thickness. Intercellular air spaces develop rapidly during the next few days, and D/N decreases in value to about 130 μ. Subsequently, the leaf cells increase in size with no substantial further increase in the number of intercellular air spaces. This final growth phase is characterized by a slight increase in D/N to a maximum value of about 140 μ. Maximum reflectance of the leaf corresponds to a minimum value of D/N. The parameter D/N is highly correlated with the amount of intercellular air spaces in a leaf.

© 1970 Optical Society of America

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References

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  1. E. C. Humphries, A. W. Wheeler, Ann. Rev. Plant Physiol. 14, 385 (1963).
    [CrossRef]
  2. D. Hammond, Amer. J. Botany 28, 124 (1941).
    [CrossRef]
  3. G. S. Avery, Amer. J. Botany 20, 565 (1933).
    [CrossRef]
  4. F. M. Scott, M. R. Schroeder, F. M. Turrell, Botan. Gaz. 109, 381 (1948).
    [CrossRef]
  5. N. Sunderland, J. Exp. Botany 11, 68 (1960).
    [CrossRef]
  6. B. P. Strogonov, Physiological Basis of Salt Tolerance of Plants (Transl. by Israel Program for Scientific Translations, 1964) (Daniel Davey & Co., Inc., New York, 1962), p. 83.
  7. R. Brouwer, Acta Botan. Neerl. 12, 248 (1963).
  8. R. H. Nieman, Plant Physiol. 40, 156 (1965).
    [CrossRef] [PubMed]
  9. F. M. Turrell, M. E. Turrell, Proc. Iowa Acad. Sci. 50, 185 (1934).
  10. H. W. Gausman, R. Cardenas, Agron. J. 60, 566 (1968).
    [CrossRef]
  11. R. O. Slatyer, Plant-Water Relationships (Academic Press Inc., New York, 1967), Chap. 7, p. 218.
  12. F. M. Turrell, Amer. J. Botany 23, 255 (1936).
    [CrossRef]
  13. K. Esau, Plant Anatomy. (John Wiley & Sons, Inc., New York, 1965), Chap. 16, p. 430.
  14. W. A. Allen, A. J. Richardson, J. Opt. Soc. Amer. 58, 1023 (1968).
    [CrossRef]
  15. V. P. Kubelka, F. Munk, Z. Tech. Physik 12, 593 (1931).
  16. R. Willstätter, A. Stoll, Untersuchunger über die Assimilation der Kohlensaure (Julius Springer-Verlag, Berlin, 1913), p. 122.
  17. D. M. Gates, H. J. Keegan, J. C. Schleter, V. R. Weidner, Appl. Opt. 4, 11 (1965).
    [CrossRef]
  18. T. R. Sinclair, M. S. thesis, Purdue University Library, Lafayette, Indiana, p. 126.
  19. V. I. Myers, W. A. Allen, Appl. Opt. 7, 1819 (1968).
    [CrossRef] [PubMed]
  20. H. W. Gausman, W. A. Allen, R. Cardenas, Remote Sens. Environ. 1, 19 (1969).
    [CrossRef]
  21. W. A. Allen, H. W. Gausman, A. J. Richardson, J. R. Thomas, J. Opt. Soc. Amer. 59, 1376 (1969).
    [CrossRef]
  22. D. R. Hoagland, D. I. Arnon, Calif. Agr. Exp. Sta. Circ. 347, 36 (1938).
  23. R. H. Nieman, L. L. Poulsen, Botan. Gaz. 128, 69 (1967).
    [CrossRef]
  24. Trade names are included for information only and do not constitute endorsement by the U.S. Department of Agriculture.
  25. M. D. Heilman, C. L. Gonzalez, W. A. Swanson, W. J. Rippert, Agron. J. 60, 578 (1968).
    [CrossRef]
  26. R. E. Johnson, Agron. J. 59, 493 (1967).
    [CrossRef]
  27. C. L. Sanders, E. E. K. Middleton, J. Opt. Soc. Amer. 43, 58 (1953).
    [CrossRef]
  28. W. A. Jensen, Botanical Histochemistry (W. H. Freeman & Co., San Francisco, 1962), Chap. 4, p. 90.
  29. R. G. D. Steel, J. H. Torrie, Principles and Procedures of Statistics (McGraw-Hill Book Company, New York, 1960), Chap. 7, p. 107.
  30. G. G. Stokes, Proc. Roy. Soc. (London) 11, 545 (1862).
  31. G. W. Ingle, “Note on the coincidence of equations for the reflectance of translucent films,” ASTM Bull.116 (May1942).
  32. H. E. Hayward, The Structure of Economic Plants (The Macmillan Company, New York, 1951), p. 433.
  33. F. P. Weber, C. E. Olson, “Remote Sensing Implications of Changes in Physiologic Structure and Functions of Tree Seedlings under Moisture Stress,” Ann. Prog. Rep. for Remote Sensing Lab. for Natural Resource Program, NASA, by the Pacific Southwest Forest and Range Exp. Sta. (1967).
  34. H. Lundegårdh, Plant Physiology (American Elsevier Publishing Co., New York, 1966), Chap. 2, p. 76.
  35. J. A. Curcio, C. C. Petty, J. Opt. Soc. Amer. 41, 302 (1951).
    [CrossRef]

1969 (2)

H. W. Gausman, W. A. Allen, R. Cardenas, Remote Sens. Environ. 1, 19 (1969).
[CrossRef]

W. A. Allen, H. W. Gausman, A. J. Richardson, J. R. Thomas, J. Opt. Soc. Amer. 59, 1376 (1969).
[CrossRef]

1968 (4)

V. I. Myers, W. A. Allen, Appl. Opt. 7, 1819 (1968).
[CrossRef] [PubMed]

W. A. Allen, A. J. Richardson, J. Opt. Soc. Amer. 58, 1023 (1968).
[CrossRef]

H. W. Gausman, R. Cardenas, Agron. J. 60, 566 (1968).
[CrossRef]

M. D. Heilman, C. L. Gonzalez, W. A. Swanson, W. J. Rippert, Agron. J. 60, 578 (1968).
[CrossRef]

1967 (2)

R. E. Johnson, Agron. J. 59, 493 (1967).
[CrossRef]

R. H. Nieman, L. L. Poulsen, Botan. Gaz. 128, 69 (1967).
[CrossRef]

1965 (2)

1963 (2)

E. C. Humphries, A. W. Wheeler, Ann. Rev. Plant Physiol. 14, 385 (1963).
[CrossRef]

R. Brouwer, Acta Botan. Neerl. 12, 248 (1963).

1960 (1)

N. Sunderland, J. Exp. Botany 11, 68 (1960).
[CrossRef]

1953 (1)

C. L. Sanders, E. E. K. Middleton, J. Opt. Soc. Amer. 43, 58 (1953).
[CrossRef]

1951 (1)

J. A. Curcio, C. C. Petty, J. Opt. Soc. Amer. 41, 302 (1951).
[CrossRef]

1948 (1)

F. M. Scott, M. R. Schroeder, F. M. Turrell, Botan. Gaz. 109, 381 (1948).
[CrossRef]

1942 (1)

G. W. Ingle, “Note on the coincidence of equations for the reflectance of translucent films,” ASTM Bull.116 (May1942).

1941 (1)

D. Hammond, Amer. J. Botany 28, 124 (1941).
[CrossRef]

1938 (1)

D. R. Hoagland, D. I. Arnon, Calif. Agr. Exp. Sta. Circ. 347, 36 (1938).

1936 (1)

F. M. Turrell, Amer. J. Botany 23, 255 (1936).
[CrossRef]

1934 (1)

F. M. Turrell, M. E. Turrell, Proc. Iowa Acad. Sci. 50, 185 (1934).

1933 (1)

G. S. Avery, Amer. J. Botany 20, 565 (1933).
[CrossRef]

1931 (1)

V. P. Kubelka, F. Munk, Z. Tech. Physik 12, 593 (1931).

1862 (1)

G. G. Stokes, Proc. Roy. Soc. (London) 11, 545 (1862).

Allen, W. A.

H. W. Gausman, W. A. Allen, R. Cardenas, Remote Sens. Environ. 1, 19 (1969).
[CrossRef]

W. A. Allen, H. W. Gausman, A. J. Richardson, J. R. Thomas, J. Opt. Soc. Amer. 59, 1376 (1969).
[CrossRef]

V. I. Myers, W. A. Allen, Appl. Opt. 7, 1819 (1968).
[CrossRef] [PubMed]

W. A. Allen, A. J. Richardson, J. Opt. Soc. Amer. 58, 1023 (1968).
[CrossRef]

Arnon, D. I.

D. R. Hoagland, D. I. Arnon, Calif. Agr. Exp. Sta. Circ. 347, 36 (1938).

Avery, G. S.

G. S. Avery, Amer. J. Botany 20, 565 (1933).
[CrossRef]

Brouwer, R.

R. Brouwer, Acta Botan. Neerl. 12, 248 (1963).

Cardenas, R.

H. W. Gausman, W. A. Allen, R. Cardenas, Remote Sens. Environ. 1, 19 (1969).
[CrossRef]

H. W. Gausman, R. Cardenas, Agron. J. 60, 566 (1968).
[CrossRef]

Curcio, J. A.

J. A. Curcio, C. C. Petty, J. Opt. Soc. Amer. 41, 302 (1951).
[CrossRef]

Esau, K.

K. Esau, Plant Anatomy. (John Wiley & Sons, Inc., New York, 1965), Chap. 16, p. 430.

Gates, D. M.

Gausman, H. W.

H. W. Gausman, W. A. Allen, R. Cardenas, Remote Sens. Environ. 1, 19 (1969).
[CrossRef]

W. A. Allen, H. W. Gausman, A. J. Richardson, J. R. Thomas, J. Opt. Soc. Amer. 59, 1376 (1969).
[CrossRef]

H. W. Gausman, R. Cardenas, Agron. J. 60, 566 (1968).
[CrossRef]

Gonzalez, C. L.

M. D. Heilman, C. L. Gonzalez, W. A. Swanson, W. J. Rippert, Agron. J. 60, 578 (1968).
[CrossRef]

Hammond, D.

D. Hammond, Amer. J. Botany 28, 124 (1941).
[CrossRef]

Hayward, H. E.

H. E. Hayward, The Structure of Economic Plants (The Macmillan Company, New York, 1951), p. 433.

Heilman, M. D.

M. D. Heilman, C. L. Gonzalez, W. A. Swanson, W. J. Rippert, Agron. J. 60, 578 (1968).
[CrossRef]

Hoagland, D. R.

D. R. Hoagland, D. I. Arnon, Calif. Agr. Exp. Sta. Circ. 347, 36 (1938).

Humphries, E. C.

E. C. Humphries, A. W. Wheeler, Ann. Rev. Plant Physiol. 14, 385 (1963).
[CrossRef]

Ingle, G. W.

G. W. Ingle, “Note on the coincidence of equations for the reflectance of translucent films,” ASTM Bull.116 (May1942).

Jensen, W. A.

W. A. Jensen, Botanical Histochemistry (W. H. Freeman & Co., San Francisco, 1962), Chap. 4, p. 90.

Johnson, R. E.

R. E. Johnson, Agron. J. 59, 493 (1967).
[CrossRef]

Keegan, H. J.

Kubelka, V. P.

V. P. Kubelka, F. Munk, Z. Tech. Physik 12, 593 (1931).

Lundegårdh, H.

H. Lundegårdh, Plant Physiology (American Elsevier Publishing Co., New York, 1966), Chap. 2, p. 76.

Middleton, E. E. K.

C. L. Sanders, E. E. K. Middleton, J. Opt. Soc. Amer. 43, 58 (1953).
[CrossRef]

Munk, F.

V. P. Kubelka, F. Munk, Z. Tech. Physik 12, 593 (1931).

Myers, V. I.

Nieman, R. H.

R. H. Nieman, L. L. Poulsen, Botan. Gaz. 128, 69 (1967).
[CrossRef]

R. H. Nieman, Plant Physiol. 40, 156 (1965).
[CrossRef] [PubMed]

Olson, C. E.

F. P. Weber, C. E. Olson, “Remote Sensing Implications of Changes in Physiologic Structure and Functions of Tree Seedlings under Moisture Stress,” Ann. Prog. Rep. for Remote Sensing Lab. for Natural Resource Program, NASA, by the Pacific Southwest Forest and Range Exp. Sta. (1967).

Petty, C. C.

J. A. Curcio, C. C. Petty, J. Opt. Soc. Amer. 41, 302 (1951).
[CrossRef]

Poulsen, L. L.

R. H. Nieman, L. L. Poulsen, Botan. Gaz. 128, 69 (1967).
[CrossRef]

Richardson, A. J.

W. A. Allen, H. W. Gausman, A. J. Richardson, J. R. Thomas, J. Opt. Soc. Amer. 59, 1376 (1969).
[CrossRef]

W. A. Allen, A. J. Richardson, J. Opt. Soc. Amer. 58, 1023 (1968).
[CrossRef]

Rippert, W. J.

M. D. Heilman, C. L. Gonzalez, W. A. Swanson, W. J. Rippert, Agron. J. 60, 578 (1968).
[CrossRef]

Sanders, C. L.

C. L. Sanders, E. E. K. Middleton, J. Opt. Soc. Amer. 43, 58 (1953).
[CrossRef]

Schleter, J. C.

Schroeder, M. R.

F. M. Scott, M. R. Schroeder, F. M. Turrell, Botan. Gaz. 109, 381 (1948).
[CrossRef]

Scott, F. M.

F. M. Scott, M. R. Schroeder, F. M. Turrell, Botan. Gaz. 109, 381 (1948).
[CrossRef]

Sinclair, T. R.

T. R. Sinclair, M. S. thesis, Purdue University Library, Lafayette, Indiana, p. 126.

Slatyer, R. O.

R. O. Slatyer, Plant-Water Relationships (Academic Press Inc., New York, 1967), Chap. 7, p. 218.

Steel, R. G. D.

R. G. D. Steel, J. H. Torrie, Principles and Procedures of Statistics (McGraw-Hill Book Company, New York, 1960), Chap. 7, p. 107.

Stokes, G. G.

G. G. Stokes, Proc. Roy. Soc. (London) 11, 545 (1862).

Stoll, A.

R. Willstätter, A. Stoll, Untersuchunger über die Assimilation der Kohlensaure (Julius Springer-Verlag, Berlin, 1913), p. 122.

Strogonov, B. P.

B. P. Strogonov, Physiological Basis of Salt Tolerance of Plants (Transl. by Israel Program for Scientific Translations, 1964) (Daniel Davey & Co., Inc., New York, 1962), p. 83.

Sunderland, N.

N. Sunderland, J. Exp. Botany 11, 68 (1960).
[CrossRef]

Swanson, W. A.

M. D. Heilman, C. L. Gonzalez, W. A. Swanson, W. J. Rippert, Agron. J. 60, 578 (1968).
[CrossRef]

Thomas, J. R.

W. A. Allen, H. W. Gausman, A. J. Richardson, J. R. Thomas, J. Opt. Soc. Amer. 59, 1376 (1969).
[CrossRef]

Torrie, J. H.

R. G. D. Steel, J. H. Torrie, Principles and Procedures of Statistics (McGraw-Hill Book Company, New York, 1960), Chap. 7, p. 107.

Turrell, F. M.

F. M. Scott, M. R. Schroeder, F. M. Turrell, Botan. Gaz. 109, 381 (1948).
[CrossRef]

F. M. Turrell, Amer. J. Botany 23, 255 (1936).
[CrossRef]

F. M. Turrell, M. E. Turrell, Proc. Iowa Acad. Sci. 50, 185 (1934).

Turrell, M. E.

F. M. Turrell, M. E. Turrell, Proc. Iowa Acad. Sci. 50, 185 (1934).

Weber, F. P.

F. P. Weber, C. E. Olson, “Remote Sensing Implications of Changes in Physiologic Structure and Functions of Tree Seedlings under Moisture Stress,” Ann. Prog. Rep. for Remote Sensing Lab. for Natural Resource Program, NASA, by the Pacific Southwest Forest and Range Exp. Sta. (1967).

Weidner, V. R.

Wheeler, A. W.

E. C. Humphries, A. W. Wheeler, Ann. Rev. Plant Physiol. 14, 385 (1963).
[CrossRef]

Willstätter, R.

R. Willstätter, A. Stoll, Untersuchunger über die Assimilation der Kohlensaure (Julius Springer-Verlag, Berlin, 1913), p. 122.

Acta Botan. Neerl. (1)

R. Brouwer, Acta Botan. Neerl. 12, 248 (1963).

Agron. J. (3)

H. W. Gausman, R. Cardenas, Agron. J. 60, 566 (1968).
[CrossRef]

M. D. Heilman, C. L. Gonzalez, W. A. Swanson, W. J. Rippert, Agron. J. 60, 578 (1968).
[CrossRef]

R. E. Johnson, Agron. J. 59, 493 (1967).
[CrossRef]

Amer. J. Botany (3)

D. Hammond, Amer. J. Botany 28, 124 (1941).
[CrossRef]

G. S. Avery, Amer. J. Botany 20, 565 (1933).
[CrossRef]

F. M. Turrell, Amer. J. Botany 23, 255 (1936).
[CrossRef]

Ann. Rev. Plant Physiol. (1)

E. C. Humphries, A. W. Wheeler, Ann. Rev. Plant Physiol. 14, 385 (1963).
[CrossRef]

Appl. Opt. (2)

ASTM Bull. (1)

G. W. Ingle, “Note on the coincidence of equations for the reflectance of translucent films,” ASTM Bull.116 (May1942).

Botan. Gaz. (2)

R. H. Nieman, L. L. Poulsen, Botan. Gaz. 128, 69 (1967).
[CrossRef]

F. M. Scott, M. R. Schroeder, F. M. Turrell, Botan. Gaz. 109, 381 (1948).
[CrossRef]

Calif. Agr. Exp. Sta. Circ. (1)

D. R. Hoagland, D. I. Arnon, Calif. Agr. Exp. Sta. Circ. 347, 36 (1938).

J. Exp. Botany (1)

N. Sunderland, J. Exp. Botany 11, 68 (1960).
[CrossRef]

J. Opt. Soc. Amer. (4)

W. A. Allen, A. J. Richardson, J. Opt. Soc. Amer. 58, 1023 (1968).
[CrossRef]

J. A. Curcio, C. C. Petty, J. Opt. Soc. Amer. 41, 302 (1951).
[CrossRef]

W. A. Allen, H. W. Gausman, A. J. Richardson, J. R. Thomas, J. Opt. Soc. Amer. 59, 1376 (1969).
[CrossRef]

C. L. Sanders, E. E. K. Middleton, J. Opt. Soc. Amer. 43, 58 (1953).
[CrossRef]

Plant Physiol. (1)

R. H. Nieman, Plant Physiol. 40, 156 (1965).
[CrossRef] [PubMed]

Proc. Iowa Acad. Sci. (1)

F. M. Turrell, M. E. Turrell, Proc. Iowa Acad. Sci. 50, 185 (1934).

Proc. Roy. Soc. (London) (1)

G. G. Stokes, Proc. Roy. Soc. (London) 11, 545 (1862).

Remote Sens. Environ. (1)

H. W. Gausman, W. A. Allen, R. Cardenas, Remote Sens. Environ. 1, 19 (1969).
[CrossRef]

Z. Tech. Physik (1)

V. P. Kubelka, F. Munk, Z. Tech. Physik 12, 593 (1931).

Other (11)

R. Willstätter, A. Stoll, Untersuchunger über die Assimilation der Kohlensaure (Julius Springer-Verlag, Berlin, 1913), p. 122.

K. Esau, Plant Anatomy. (John Wiley & Sons, Inc., New York, 1965), Chap. 16, p. 430.

T. R. Sinclair, M. S. thesis, Purdue University Library, Lafayette, Indiana, p. 126.

R. O. Slatyer, Plant-Water Relationships (Academic Press Inc., New York, 1967), Chap. 7, p. 218.

B. P. Strogonov, Physiological Basis of Salt Tolerance of Plants (Transl. by Israel Program for Scientific Translations, 1964) (Daniel Davey & Co., Inc., New York, 1962), p. 83.

H. E. Hayward, The Structure of Economic Plants (The Macmillan Company, New York, 1951), p. 433.

F. P. Weber, C. E. Olson, “Remote Sensing Implications of Changes in Physiologic Structure and Functions of Tree Seedlings under Moisture Stress,” Ann. Prog. Rep. for Remote Sensing Lab. for Natural Resource Program, NASA, by the Pacific Southwest Forest and Range Exp. Sta. (1967).

H. Lundegårdh, Plant Physiology (American Elsevier Publishing Co., New York, 1966), Chap. 2, p. 76.

W. A. Jensen, Botanical Histochemistry (W. H. Freeman & Co., San Francisco, 1962), Chap. 4, p. 90.

R. G. D. Steel, J. H. Torrie, Principles and Procedures of Statistics (McGraw-Hill Book Company, New York, 1960), Chap. 7, p. 107.

Trade names are included for information only and do not constitute endorsement by the U.S. Department of Agriculture.

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Figures (10)

Fig. 1
Fig. 1

Percent light reflectance from upper surfaces of third true leaves of different chronological ages from growth-chamber-grown cotton plants. Each spectrum is the mean for four leaves.

Fig. 2
Fig. 2

Percent light reflectance from upper surfaces of approximately the twentieth true leaves of different chronological ages from field-grown cotton plants. Each spectrum is the mean for four leaves.

Fig. 3
Fig. 3

Percent light transmittance of third true leaves of different chronological ages from growth-chamber-grown cotton plants. Each spectrum is the mean for four leaves.

Fig. 4
Fig. 4

Transverse sections of leaves showing the relation between leaf maturity and numbers of intercellular spaces. Upper and lower photomicrographs represent leaves with average after-tagging ages of 3.5 days and 10.8 days, respectively.

Fig. 5
Fig. 5

Relation between the growth of cotton leaves in surface area (horizontal direction) and thickness. Each after tagging age is an average of four replications.

Fig. 6
Fig. 6

Equivalent water thickness (EWT) of a maturing cotton leaf. Open circles represent spectrophotometry values and solid circles are experimental data.

Fig. 7
Fig. 7

Void area index (VAI) of a maturing cotton leaf.

Fig. 8
Fig. 8

Effective dispersion curve of a maturing cotton leaf.

Fig. 9
Fig. 9

Effective absorption curve of a maturing cotton leaf. Solid points are values for pure liquid water (Ref. 35).

Fig. 10
Fig. 10

Mean free path between refraction of a light ray within a cotton leaf.

Tables (1)

Tables Icon

Table I Effects of Cotton Leaf Maturation on Characteristics of Their Intercellular Spaces in Transverse Leaf Sections. Data are Averages of Counts and Planimetry Measurements from Five Photomicrographic Prints Within Each After-Tagging Age for Four Replications

Equations (7)

Equations on this page are rendered with MathJax. Learn more.

t a a 1 = r b b 1 = 1 a b a 1 b 1 ,
t a 0 a 0 1 = r b 0 N b 0 N = 1 a 0 b 0 N a 0 1 b 0 N ,
a = a 0 , b = b 0 N .
t 0 a 0 a 0 1 = r 0 b 0 b 0 1 = 1 a c b 0 a 0 1 b 0 1 .
t 0 a a 1 = r 0 b 1 / N b 1 / N = 1 a b 1 / N a 1 b 1 / N .
s = [ 2 a / ( a 2 1 ) ] log b , s 0 = [ 2 a 0 / ( a 0 2 1 ) ] log b 0 .
s / s 0 = N .

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