Basis Of Tolerance Research Articles

Basis for Variability in the Cucumber for Tolerance to Chloramben Methyl Ester

The physiological basis for tolerance and susceptibility of four lines of cucumber (Cucumis sativusL.) to the methyl ester of 3-amino-2,5-dichlorobenzoic acid (chloramben) was investigated. ‘MSU 3207’ and ‘MSU 0612’ were tolerant (T), whereas ‘MSU 3159’ and ‘MSU 0866’ were susceptible (S). Intraspecific variability was related to higher concentrations of chloramben in the roots of the susceptible lines, resulting from metabolic differences in these lines and rapid absorption of the herbicide by the roots of ‘S-MSU 3159’. Tolerance of ‘T-MSU 3207’ resulted primarily from low uptake and reduced translocation of the herbicide, while tolerance of ‘T-MSU 0612’ was related to, but not necessarily explained by, a peculiar14C-label distribution pattern in the leaves. Thin-layer chromatographic analysis of methanol-soluble extracts from the lines studied 3 days after14C-chloramben methyl ester treatment separated six14C-metabolites in the roots and five in the shoots. After a 4-hr treatment,14C-chloramben methyl ester was absorbed and translocated more rapidly than14C-chloramben by all four lines. Tolerance or susceptibility did not always correlate with the total concentration of radioactivity in methanol-soluble shoot and root extracts.

An Attempt to Improve Tolerance to Homografts in Chickens by Selection

NONAVAILABILITY of histocompatability lines in chickens has restricted their use as suitable genetic material for the study of immunologic and tolerance phenomena. Inbreeding has been practiced in the past (Cock and Clough, 1956; Crittenden et al., 1964; and Hasek et al., 1966) to increase the homograft acceptance in chickens, although complete homozygosity for histocompatibility genes was not reported until recently. Hasek et al. (1966) have been successful in producing histocompatible sublines (CA, CB, CC and CD) of an inbred C line of White Leghorn chickens by further inbreeding and selection for identity in homograft acceptance and erythrocyte antigens.The present work was planned to avoid long term inbreeding and the probable consequences of reduced reproductive ability of chickens (Crittenden et al., 1964; and Hasek et al., 1966). There seemed a good possibility that histocompatible lines with a minimum of inbreeding could be established by selection on the basis of tolerance…

Cellular Aspects of Immune Reactions

During the last few years, a penetrating insight into the cellular basis of tolerance, hypersensitivity, and immunity has been obtained by the focus of anatomists, immunologists, biochemists, and clinical scientists upon these states. In this report, the study of blood cells, their origin and their function in relation to immunological reactions, is presented to demonstrate the substantial progress made in recent years. The recent surgical success of organ transplantation has intensified interest in the function of these cells. The results of basic research in the field of immune responses show great promise for practical application in promoting resistance to specific infections, advancing homotransplantation of organs and combating autoimmunity. A basic requisite for survival of living organisms is the recognition, isolation, and elimination of pathogenic agents. These functions are performed

Factors of Unity and Factors of Conflict

Russian and Chinese national interests tend to ward opposition. The Sino-Soviet alliance is wholly due to seizure of power by Chinese Communists and to conflict with the same enemies. Economic, military, and diplomatic dis parities have created a lopsided material dependence of Com munist China on the Soviet Union, resulting in divergent views on priorities within the alliance, and have caused them to dis agree on proper strategy in relation to the United States, anti- imperialist revolutionary movements, and independent neutral powers. Among states governed by totalitarian, ideological parties, these disagreements have naturally assumed the form of different interpretations of the common doctrine. Lacking other means of effective pressure on the Soviets, the Chinese have developed these differences into a systematic challenge to Soviet ideological authority. A Soviet attempt to evade this challenge and to preserve unity on the basis of toleration of in evitable differences and adjustment by compromise has failed; both sides have recognized the inevitability of factional schism for some time. They have built two rival Communist camps with separate policies. Underlying opposition of national in terests is increasingly appearing, and doctrinal differences are hardening. Though a serious attempt to return to policy co ordination is unlikely, the formal bond of the alliance may well continue as reinsurance against the common enemy so long as both countries are ruled by Communist party regimes.

On the measurement and interpretation of non-linearity in a television system

A mathematical description of a general non-linear system is used to illustrate the scope of presently defined non-linearity measurements and to indicate how these may be extended. Present methods of interpretation of the results obtained from non-linearity measurements are discussed, leading to a more subjective assessment of the results being suggested as the basis of tolerances. Areas for further study in this field are also indicated.

The Basis of Tolerance in a Democratic Society

The Basis of Tolerance in a Democratic Society