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The object of the study was to investigate the genetic nature of personal preferences in such spheres as food, friendship, art, music, ambition, marriage and so on. The subjects chosen for the research were forty-eight pairs of identical and forty-eight pairs of non-identical twins, divided equally into males and females, with ages ranging between 17 and 40 years. Each subject, individually, was given an oral questionnaire (‘Fads and Fancies’), the answers to which were analysed statistically. The results indicate very little difference between the concordance rates of identical and non-identical twins, suggesting that the issues discussed might not be genetically influenced. One possible reason for such findings could be the unrepresentative nature of the sample. [ABSTRACT FROM PUBLISHER]

Exudation from the xylem of excised maize roots was studied in roots bathed in solutions containing kinetin or abscisic acid (ABA). Kinetin reduced the water permeability of the roots whilst ABA increased it. The action of both hormones was reversible and both were effective at concentrations of 10-6M and below. The possible in vivo role of these two hormones is discussed. [ABSTRACT FROM AUTHOR]

When Fe-inefficient T3238fer and Fe-efficient T3238FER tomatoes were supplied iron, and nitrogen as nitrate, they increased the pH of the nutrient culture. When they were supplied nitrogen as ammonium, they decreased the pH. When Fe supply was limited, Fe-stress response developed in T3238FER that opposed the usual nitrate response and decreased, rather than increased, the pH. A "reductant" which reduced Fe3+ to Fe2+ was released from the roots of these plants and lowered the pH; and there was a tremendous increase in the uptake of Fe. T3238fer did not produce "reductant" in response to Fe-stress; the pH increased, and the plants developed Fe-deficiency when nitrogen was supplied as nitrate. Nitrogen nutrition and iron-stress response are important factors associated with iron chlorosis in plants. Release of hydrogen ions from roots of Fe-stressed plants is caused by more than response to imbalanced uptake of cations and anions. [ABSTRACT FROM AUTHOR]

Examines the trophic levels in desert ecosystems. Importance of heat balance, food and water for desert animals; Influence of space-time distribution in arid ecosystems; Complexity of the food web in the ecosystem.

The contents of Ca and P in developing enamel of the continuously growing rat incisor were examined by the electron microprobe. A longitudinally sectioned, epoxy resin-embedded maxillary incisor from a 5-month-old rat was analyzed by linear scans across the enamel at intervals from the growing end. Near the growing end, concentrations of approximately 2 % Ca and 1 % P were found close to the ameloblast-enamel junction, in- creasing to 18 % Ca and 9 % p near the dentino-enamel junction. With increaing distance from the growing end, a successive increase of the mineral content was observed, together with a leveling out of the concentration gradients from the enamel surface to the amelo-dentinal junction seen at earlier stages of mineralization. Mature enamel contained about 35 % Ca and 17 % P. The results were discussed in the light of previous electron microscopic observations of the same specimen material. It was concluded that in analysis of mineralized tissues in an early stage of development, the mineral content as found by tile electron microprobe technique can be considered a valid approximation of the true situation. This technique may also be applied to the study of hard tissues in varying stages of demin-eralization. [ABSTRACT FROM AUTHOR]

In a study of grazing interactions of Blackface sheep, red grouse and mountain hare on a hill grazing in the Pentland Hills, Scotland, the variation in the mineral content of nine vegetation types were investigated. The estimated number of samples required to absorb spatial variation varied with the element determined and the vegetation type making it difficult to define an effective sampling program. A two-stage procedure appears to be the most useful approach. Within season variation was considerable but had a similar pattern for like vegetation.

Studies the effect of mowing on the feeding preferences of wigeon (Anas penelope L.). Part of a wider study aimed at integrating wigeon conservation and agricultural practice, with the minimum management; Basis for management of a salt marsh to retain suitability of the area as a wigeon feeding ground; Pilot turf cutting experiment on Festuca swards.

Three formulas with different fat blends were fed to 29 infants from the fourth to the tenth days of life. Absorption and retention of fat, calcium, and phosphorus were measured by a metabolic balance technique. The following observations were made: 1. Absorption of oleate and linoleate was best with the formula that had a linoleate:oleate ratio similar to that of human milk. Absorption of palmitate was similar with all three formulas. Stearate absorption was low in the formula with the lowest stearate content. 2. Calcium absorption was 36 mg/kg/day or 38% of intake with the formula which had a linoleate:stearate ratio similar to that of human milk; this was significantly greater than with the other two formulas which both had much higher linoleate:oleate ratios. 3. Phosphorus absorption was approximately 90% of intake with all three formulas, equivalent to 47 to 79 mg/kg/day. Retention varied from 27 to 53 mg/kg/day. [ABSTRACT FROM AUTHOR]

The distribution of pollen upon the insect-visitors to three species of Viola is described and correlated with their feeding and cleaning behaviour. Visitors adopt one of two basic positions while feeding. In the prone position the insect alights on the anterior petal and probes for nectar so that its dorsal surfaces contact the floral genitalia. The supine position may be adopted after alighting on the anterior petal when the insect rotates so that it is virtually standing on its head. While probing for nectar from this position it is the ventral surfaces which contact the floral genitalia. Bumblebees adopt either feeding position; many large solitary bee species almost invariably adopt the supine one while large hoverflies always feed from the prone position. The behaviour of short-tongued visitors tends to be highly individual with respect to contact with the floral genitalia and many body surfaces may be involved. The varying activities of insect-visitors while feeding result in the deposition of pollen at different locations on the integument. Consequently insect-borne pollen is presented to the stigma in various ways and there is a spectrum of pollination effects: medium and long-tongued nectar-seeking insects tend to be systematic cross-pollinators while short-tongued or pollen-gathering species tend to be chance cross- or self-pollinators. The cleaning behaviour of insect-visitors strongly influences pollination as it removes much integumental pollen. Two requirements of the pollen deposition mechanism are postulated: that pollen should be placed (a) in a position not occupied by foreign pollen and (b) in a position irregularly or inefficiently cleaned. There were no positions which were free of foreign pollen throughout the visitor-species. On the other hand, violet pollen was found to be concentrated at locations inaccessible to the cleaning mechanism. [ABSTRACT FROM AUTHOR]

Huntington's conclusions relating to food and diets and their relevance to health in Mainsprings of Civilization arc no longer acceptable owing to his incorrect evaluations resulting from inaccurate assumptions in two major categories: 1) critical characteristics of food composition, and 2) nutritional requirements for health. The critical nutritional problem in international perspective relates predominantly to protein quality, its availability, production, and consumption. Agricultural geographers with this view in mind can plan more effective programs and more critically evaluate the important elements of the growing pressure of the food-available land relationship. [ABSTRACT FROM AUTHOR]

Reports on the use of food, drinks and sweets in the reduction of industrial fatigue. Causes of fatigue; Strategies for minimizing fatigue and distress; Role of food, drinks and sweets in raising the threshold of fatigue and distress.

Describes the feeding patterns of the wigeon, in order to provide criteria necessary for testing the efficacy of various methods of pasture management at Bridgwater Bay National Nature Reserve in Somerset, England. Factors responsible for decrease in numbers of wigeon; Measures needed to conserve the number of wigeon.

Studies the diet of cattle egrets feeding in man-made pastures in the south-western Cape Province, South Africa. Description of materials and methods used; Diet of independent free-flying birds; Diversity of food by individual birds and time of day; Diet of nestling birds; Variables affecting the diet of Ardeola ibis; Importance of grasshoppers and caterpillars in the diet of egrets.

Rats were fed for 3-4 weeks from weaning either a control carbohydrate diet (58% starch) or one of two fat diets (35.5% and 58% lard); some rats were changed from fat (35.5%) to control diet 1 to 5 days before the experiment. Epididymal adipose tissue was incubated in the presence of [U-14C]glucose (10 mM) and (or no) insulin (100 µU/ml). Glucose uptake and conversion into CO2, glycogen, fatty acid and glyceride-glycerol were measured together with lactate and glycerol release during a 2-hour incubation. The level of free fatty acids in tissue was also determined. Incorporations of glucose carbon into CO2 and fatty acid were severely reduced by both fat diets and increased during the first 5 days after change to control diet in an almost linear way, to values still far from the control values. After both fat diets, lactate release was doubled, accounting for half the glucose uptake. Lipolysis, measured by glycerol release, was unchanged (35.5% fat) or increased (58% fat) by fat diet, but the antilipolytic effect of insulin was entirely preserved in both fat conditions. A 6-hour preincubation of the tissue with glucose increased glucose uptake and metabolism in adipose tissue of control and fat-fed rats, independently of the presence of insulin (50 µU/ml) in the medium. This effect does not seen to have any relation with the progressive restoration of lipogenesis observed after changing the animals from fat to carbohydrate diet. [ABSTRACT FROM AUTHOR]

This article focuses on differing reactions of friendly and fear-biting dogs to severe stress. For the purposes of this study, normal "friendly' dogs were operationally defined as those who showed no fear in approaching close enough to the experimenter to be fed by hand under the conditions cited in a previous study. "Shy" animals were defined as those who would not come close enough to be touched when offered food and the degree of shyness was measured in terms of the closeness in feet which the dog approached after a 30 day friendliness training period.

The article presents information on Polar Eskimos and their dependence on material goods to satisfy their basic needs in their far Arctic environment. Polar Eskimos are dependent upon land for many of their critical supplies. From the caribou they get their sleeping bag, from the hare their stockings, from the fox the furs for some of their clothing and from the birds their bird skin underwear. They supply the Eskimos little food, that helps to relieve the monotony of their diet. Hunting on the ice continue from late September or early October when the ice is strong enough to bear the weight of hunter, sledge and dogs.

Studies the habitat of cliff dwellers in the Mesa Verde region, which is located in the extreme south western part of Colorado on the borderland of the plateau section of the Southwest and of the Rocky Mountains. Culture, ability and cultural advancement; Food sources; Physical features of the region.