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This study examines preservation of microfossils identified as introduced Ipomoea batatas in soils from northern New Zealand. Starch grains and xylem cells showed highly variable preservation, from good to extremely poor. For starch grains, the latter included brown-staining, expansion and distortion of the grain and vacuole, loss of the Maltese cross, pitting, cracking, fragmentation and disintegration. Degraded xylem showed similar brown-staining, occasional cracking, cross-wise fragmentation, with wall pits becoming progressively less visible or showing distortion, expansion and coalescence.  相似文献   
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In 1870 Gustav Fritsch and Edvard Hitzig showed that electrical stimulation of the cerebral cortex of a dog produced movements. This was a crucial event in the development of modern neuroscience because it was the first good experimental evidence for a) cerebral cortex involvement in motor function, b) the electrical excitability of the cortex, c) topographic representation in the brain, and d) localization of function in different regions of the cerebral cortex. This paper discusses their experiment and some developments in the previous two centuries that led to it including the ideas of Thomas Willis and Emanuel Swedenborg, the widespread interest in electricity and the localizations of function of Franz Joseph Gall, John Hughlings Jackson, and Paul Broca. We also consider the subsequent study of the motor cortex by David Ferrier and others.  相似文献   
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Reviews     
SPECIAL STUDY ON ECONOMIC CONDITIONS IN NON‐SELF‐GOVERNING TERRITORIES. United Nations, N.Y., 1960. Pp. v + 42. $1.50.

LAND, “WATER AND FOOD. Herbert Addison. 2nd edition, London, Chapman & Hall, 1961. Pp. xii + 284. Stg. 21/‐.

THE ATTACK ON WORLD POVERTY. Andrew Shonfield. London, Chatto & Windus, 1960. Pp. x + 244. Australian Price 34/9.

THE ECONOMICS OF DEFENSE IN THE NUCLEAR AGE. Charles J. Hitch and Roland N. MeKean. Cambridge, Mass., Harvard University Press, 1960. Pp. xiv + 422. Australian price 98/3.

DEFENCE BY COMMITTEE. F. A. Johnson. London, Oxford University Press, 1960. Pp. viii + 416. Australian price 81/3.

EMPIRE INTO COMMONWEALTH—the Chichele Lectures, Oxford, May 1960. Earl Attlee. London, Oxford University Press, 1961. Pp. 54. Australian price 12/6.

TANGANYIKA AND INTERNATIONAL TRUSTEESHIP. B. T. G. Chidzero. For the Royal Institute of International Affairs. London, Oxford University Press, 1961. Pp. xii + 286. 2 maps. Australian price 57/9.

MULTI‐RACIAL SOUTH AFRICA. Z. J. de Beer. For the Institute of Race Relations. London, Oxford University Press, 1961. Pp. vii + 69. Australian price 10/‐.

POLITICAL AFRICA: A WHO'S WHO OF PERSONALITIES AND PARTIES. Ronald Segal. London, Stevens, 1961. Pp. xii + 475. Australian price 72/‐.

INDIA'S CONSTITUTION IN THE MAKING. B. N. Rau. Calcutta, Orient Longmans, 1960. Pp. 510. Rs. 25.

OIL IN THE MIDDLE EAST. S. H. Longrigg. For the Royal Institute of International Affairs. London, Oxford University Press, 1961. Pp. xiii + 401. Australian price 55/6.

TRADE PROTECTION IN AUSTRALIA. A. J. Reitsma. Leiden and Brisbane. H. E. Stenfert Kroese and University of Queensland Press, 1960. Pp. xi + 195. Australian price 40/‐.

NEW MEN OF PAPUA: A STUDY IN CULTURE CHANGE. Robert F. Maher. Madison, University of Wisconsin Press, 1961, Pp. xii + 148.  相似文献   

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Following a right cerebral stroke, the German artist Anton Raederscheidt produced a remarkable series of self-portraits that depicted his severe visual neglect and gradual recovery. These distorted images, like those drawn by others with this disorder, inform us about lateral balance in art and why it is common in the art of cultures separated in time and space. After describing how artists in various cultures have employed lateral balance, I present Arnheim's view that this aspect of art is the result of visual forces generated by the brain. Following a brief history of visual neglect, I present evidence that this disorder provides us with clues to the origin of the visual forces responsible for lateral balance in art. The relevant brain mechanisms control exploration of visual space by integrating orienting movements with visual spatial information. The prevalence of lateral balance in art becomes understandable when we consider that these brain mechanisms evolved to promote survival in our vertebrate ancestors. I end with a speculative neurological account of the aesthetics of lateral balance--why it is pleasing and its absence is displeasing.  相似文献   
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