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FOODS ARE OFTEN blamed when persons, otherwise healthy, complain of heartburn, eructation, low thoracic or abdominal burning, "hyperacidity," abdominal fullness, bloating, pressure, aching, pain, "gas," borborygmi, excessive "activity," flatulence, constipation, and diarrhea. When gastrointestinal disorders underlie such symptoms, their degree is believed to be enhanced by some foods and diminished by others. To evaluate the validity of such correlations between food and gastrointestinal symptomatology, the committee has surveyed current dietary practices and has critically examined the rationale and much of the evidence underlying such practices. The interpretations and evaluations presented here must be recognized for what they are, namely, a synthesis of tentative opinions held by committee members on the basis of their knowledge of the literature, their experience, and their discussions. Knowledge in this field is far too meager to permit authoritative or final conclusions. The report does not apply to the dietotherapy of infants and young children, nor

Koller, D. (Hebrew U., Jerusalem, Israel), H. R. Highkin, and O. H. Caso. Effects of gibberellic acid on stem apices of vernalizable grasses.Amer. Jour. Bot. 47(6) : 518–524. Illus. 1960.—Gibberellic acid was found to have distinct morphogenic effects on the stem apices of 3 vernalizable but unvernalized grasses: Hordeum vulgarevar. ‘Kentucky,’ Hordeum bulbosumand Secale cerealevar. ‘Winter Petkus.’ In these 3 species, GA caused the activation of lateral meristems on the embryonic nodes of the stem apices, under both short‐ and long‐day conditions. These lateral meristems differentiated into either flower primordia or vegetative shoots. The flower primordia developed almost invariably in Hordeum,while in Secalethey seldom did, the apical meristem usually resuming normal vegetative growth after treatment. Despite the occurrence of flowering, it is concluded that the role of GA in this phenomenon is restricted to the activation of lateral meristems in the apex.

Summary Diffusion coefficients and their temperature coefficients were obtained on a series of four polyurethanes believed to differ mainly in their molecular chain stiffness, and on one partially crystalline polyurethane of high molecular symmetry having flexible chains. The diffusion coefficients of CO2 in these materials and their temperature dependence are f ound to be much lower than those of many other typical organic polymers, notably rubbers. The data are interpreted in terms of theH-bonds formed between neighbouring polymer chains which are thought to make for regions of high packing efficiency, interrupted at irregular intervals by more open regions of small size. The effect of molecular chain flexibility appears to be smaller than the influence of theH-bonding.

Numerous methods have been evolved for the calculation of diets to be used by patients with diabetes mellitus and for the simplified instruction of patients in the use of such diets. Some of these methods involve calculations which are unnecessarily accurate in view of the variable composition of foods, as affected by such factors as the variety of seed, the soil, climatic conditions and harvesting, storage and cooking methods. The fairly common practice of instructing patients to weigh diets can be criticized for the same reason plus the fact that a patient who is "tied to a pair of scales" has much less chance of living a normal life, which is so important from a psychologic point of view. The subject of the percentage of carbohydrate in foods, particularly vegetables, has also been confusing to the patient. In general, we have found that many patients disregarded it and ate whatever

IT is known that application of gibberellic acid causes flowering of many biennials (Hyoscyamus, Apium, Brassica, Daucus, etc.)1. In these cases gibberellic acid substitutes for cold (vernalization) treatment. Treatment of winter cereals (Petkus rye2, barley3, winter wheat4) with gibberellic acid, on the contrary, has been found to have no effect on the induction of normal flowers. Chaylakhian5has reported that treatment of non-vernalized oats, variety Victory, with gibberellic acid, under short-day conditions, caused formation of an increased number of developed panicles. This was not the case under long-day conditions. Paleg and Aspinall3have reported that treatment of barley with gibberellic acid for several weeks immediately following emergence results in the formation of abnormal spikes.