Flavonoids and other phenolics of Cichorium and related members of the Lactuceae (Compositae)

Extraction of the leaves of chicory, Cichoriumintybus , revealed the presence for the first time of the 3-glucuronides of kaempferol, quercetin and isorhamnetin, the 3-glucoside of kaempferol and the 7-glucuronide of luteolin. The same compounds appear to occur throughout the genus. An aglycone survey of the leaves of 240 other members of the Lactuceae failed to reveal any other source of isorhamnetin, although quercetin and kaempferol were found as occasional constituents in 12 other genera. In Lactuca , a survey of 12 species showed eight with quercetin present. In general, though, flavonols are more uncommon than flavones and thus have more potential as taxonomic markers within the tribe. The coumarins cichoriin and aesculin and the caffeoyl-tartaric acid ester, chicoric acid, were also found to be present widely in the tribe.     

Otitis externa

Otitis externa is a widespread condition which may occur in many different forms. Allergic reactions, bacteria, pathologic changes secondary to seborrheic dermatitis, and fungi, singly or in association with each other, are among the causative factors considered. In the treatment of this condition, the diversity of causative factors which may be present must be recognized and evaluated; after one factor has been eliminated, another often remains to be conquered. The apparent confusion of reports regarding etiology and treatment is in fact due to confusion regarding the fundamental nature of the condition. Good results usually can be obtained by careful evaluation of the factors in each case and adaptation of treatment to the circumstances.     

An Inhibitor of Salt Absorption in the Root Tissues of Red Beet

The absorption of manganese ions by discs of beet-root tissueoccurs in two phases. Evidence suggests that the first is physicalin nature, the second physiological. The interval between thetwo phases becomes longer as the thickness of the discs is increasedand reasons are given for attributing this to the presence ofan inhibitor of the physiological absorption process. Aqueous extracts of beet-root contain an inhibitor of ion absorptionwhich also delays the germination of mustard and cress seeds.The extract does not affect the respiration rate of beet-roottissue.     

Mineral Metabolism and Hybrid Vigour in Rye

In rye the total phosphorus, potassium, and iron content eachincreases linearly with increase in seedling weight up to tenweeks from germination. The rate of increase of mineral withweight varies between genotypes. In F₁ families showing hybridvigour and, also, in faster growing inbred families the rateof increase of mineral with increasing weight is low comparedwith that in less vigorous families. It is suggested that amore efficient utilization of mineral material accounts in partfor the greater vigour of some F₁ and inbred genotypes.     

Midday Closure of Stomata in the Oil Palm Elaeis guineensis. Jacq.

Under natural climatic conditions in West Africa, midday closureof stomata in 3–6-year-old oil palms occurs only in thelatter half of the dry season, when soil moisture is low andair temperatures are high. Using an infiltration method, attempts were made to determinethe climatic factors which affect stomatal closure. The extentof midday closure is related closely to air temperature andshade temperature under the palm, agreeing closely with thefindings of Meidner and Heath (1959) on onion, but the aperture-temperaturecurves are different for watered and unwatered palms in thedry season, the difference being greater at higher temperatures.Watering reduces closure by changing the aperture-temperaturerelationship. Under natural conditions this effect is usuallyobscured because of lower temperatures in the dry season followingrain. During Harmattan weather, with very low relative humidities,the aperture-temperature relationship broke down. The results are discussed in relation to current views on middayclosure of stomata.