617

learnt about the successful coordination of medical,social, and public services in order to produce an efficientand reliably effective service to all patients whose life

depends on such sophisticated techniques. In particularwe wish to point out that delay in placing a patient intothe home to treat himself is all too often caused byadministrative " red tape ".

REFERENCES

Baillod, R. A., Conty, C., Ilahi, M., Konotey-Ahulu, F. I. D., Sevitt, L.,Shaldon, S. (1965) Proc. Eur. Dialysis Transplant Ass. 2, 99.

Curtis, F. K., Cole, J. J., Fellows, B. J., Tyler, L. L., Scribner, B. H.(1965) Trans. Am. Soc. artif. internal Organs, 11, 7.

Curtis, J. R., Eastwood, J. B., Smith, E. K. M., Storey, J. M., Verroust, P.,de Wardener, H. E., Wing, A. J., Wolfson, E. M. (1969) Q. Jl Med.38, 49.

Davidson, R. C., Pendras, J. P. (1967) Trans. Am. Soc. artif. internal Organs,13, 20.

Eschbach, J. W., Wilson, W. E., Peoples, R. W., Wakefield, A. W., Babb,A. L., Scribner, B. H. (1966) ibid. 12, 346.

Hampers, C. L., Merrill, J. P., Cameron, E. (1965) ibid. 11, 3.Rae, A. I., Marr, T. A., Steury, R. E., Gothberg, L. A., Davidson, R. C.

(1968) J. Am. med. Ass. 206, 92.Shaldon, S. (1968) Lancet, ii, 1347.Shambaugh, P. W., Hampers, C. L., Bailey, G. L., Snyder, D., Merrill,

J. P. (1967) Trans. Am. Soc. artif. internal Organs, 13, 41.

Round the World

JapanIn Japan we obtain more than two-thirds of our total

protein intake from plant foods, and a third of the total proteinis supplied by rice. Protein of polished rice, though presentin less quantity than in wheat flour, has the best nutritivequality among grains. If the content of two essential amino-acids-lysine and threonine-could be increased, rice couldbe a rich source of protein, comparable with animal protein.Thus, in rice growing, one of the important objects is toincrease the protein content and to change the ratio of con-stituent aminoacids. Growers have improved the chemicalconstituents in many agronomic plants, and scientists haveinduced changes in chemical components by ionising radia-tions. It is therefore to be expected that induction of muta-tions in protein content and ratio of constituent aminoacidsin rice might be detected in mutant lines with or withoutvisible characteristics.

The Institute of Radiation Breeding and the Food ResearchInstitute, both of the Ministry of Agriculture and Forestry,Japan, have cooperated in research on high-protein ricemutants since 1968. Of 700 mutant lines induced by chronicy irradiation, 71 lines have had their aminoacid content analysedwith a Hitachi, model 3B, aminoacid analyser in 1968. Theprotein content of the mutant lines varied greatly. Takingthe protein percentage of the original variety, Norin no. 8,as 100%, the content of the mutant lines varied between72.4% and 185-4%. We found two high-protein lines (morethan 170%) and two low-protein lines (less than 75%). Thehigh-protein lines, mutants nos. 4 and 5, had remarkableincreases, not only in their protein content but in the contentof lysine and threonine, which are responsible for the highernutritive value; these were increased to the same level as otheraminoacids-asparagic acid, glutamic acid, proline, glycine,alanine, valine, isoleucine, and phenylanine.Mutant lines no. 4 and 5 were selected from M2 progeny

of rice plants which had been irradiated with y rays, 150 rfor 20 hours each day, through the whole growth period,seedling stage to maturity, in 1962. They matured 60 and50 days earlier, respectively, than the original variety. Bothlines had short culms; the height of line no. 4 was shorterthan that of line no. 5. Growth habits of these lines weresimilar to those of the original variety, and all their visibletraits were stable.

On the Campus

EPIDEMIOLOGICAL ASPECTS OFSTUDENT RIOTS

G. T. STEWARTOF THE DEPARTMENT OF EPIDEMIOLOGY, SCHOOLS OF MEDICINE AND

PUBLIC HEALTH AND TROPICAL MEDICINE, TULANE UNIVERSITY,NEW ORLEANS, LOUISIANA 70112, U.S.A.

Summary The social sciences are becoming moreexact, and one area which might lend

itself to sociometric analysis is the student riot. Amathematical model is proposed which incorporatesthe total population " at risk ", the number of studentsrioting at a given time, the number of outsiders joiningin, and the numbers " immune

" to such behaviour.

The relative contributions of these numbers could bedetermined by on-the-spot and retrospective survey;

knowing them could enable observers to sort out the

probable cause or outcome of a disturbance.

INTRODUCTION

COMPARING the student populations of America,Britain, Czechoslovakia, Denmark... Zambia, thesimilarities seem greater than the differences. Super-ficially, similarity is manifested in the pattern of pro-tests, sit-ins, shut-downs, shout-downs, strikes, riots,and also by ultracasual attire, new sexual images, dis-dain of conventional standards, and other symbols of

group behaviour. But it is a mistake to assume that the

feelings which underlie these manifestations are also

superficial; some of the recent major civil revolts, whichwere initiated by students, have led, not only to reactionby authorities, but to involvement of other non-studentgroups and, in some cases, to tempestuous popularmovements. In America, these movements are smoulder-ing or at best are reaching an uneasy equilibrium withauthority; in France and Indonesia, they rocked andthen capsized the authoritarian boat. In a less dramaticbut not less dynamic way, the feelings of students inthese countries are shared in many other countries and,from time to time (Mexico, Northern Ireland, Italy, andJapan are the most recent), local eruptions remind usof this chronic unrest.Viewed analytically (or epidemiologically) these out-

breaks have certain features in common:

(a) They arise in privileged, not in underprivileged, groups(e.g., in prestige universities such as Berkeley, Columbia,Prague, Lyon, Mexico City, London).

(b) They quickly become associated with grievances of

underprivileged groups (ghetto populations, underpaid wor-kers, exploited or over-ruled people).

(c) They are politically unpredictable-as likely to attackcommunism as capitalism, social democracy, or dictatorship.

(d) They stress, sometimes to the point of anarchy, theneed for absolute do-as-you-please freedom of all individualseverywhere.

(e) They are fundamentally anti-authority. In this regard,authority is identified variously (whether political, parental,papal, academic, governmental, legal, police) as the contem-porary

"

power structure " or " establishment ". In the riots

at Howard University, Washington, D.C., and at Orangeburg,South Carolina, the Negro administration came under attackby Negro students.

(f) Though professedly pacific, they may adopt violenttactics, whether or not forceful repression is encountered.