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Greater Consumption (greater + consumption)
Selected AbstractsThe sublethal effects of tebufenozide on the precopulatory and copulatory activities of Choristoneura fumiferana and C. rosaceanaENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 3 2004Renée Dallaire Abstract The sublethal effects of tebufenozide, an ecdysone agonist, on the reproductive biology of Choristoneura fumiferana (Clem) and of Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae), treated during the larval stage, were evaluated using two treatment methods: the force-feeding method and the diet method. The percentage of mortality and the developmental time of survivors increased linearly with the concentration of tebufenozide used. This ecdysone analogue proved to be more toxic to C. fumiferana than to C. rosaceana. In C. rosaceana, the weight of males and females decreased proportionally with the dose ingested, but females were affected to a greater extent. This difference might be due to a greater consumption of the treated diet, or to a differential vulnerability to tebufenozide. Tebufenozide did not modify the pre-copulatory activities associated with chemical communication in the females. However, the consumption of tebufenozide delayed ovarian maturation, causing a reduction in the fecundity of females. Treated males had smaller spermatophores and fewer eupyrene sperms in their bursa copulatrix and spermatheca, along with lower mating success. In C. fumiferana, tebufenozide delayed the females' onset time of calling the first night after emergence, but did not affect the mean time spent calling or the production of the main component of the sex pheromone. The males showed significantly greater difficulty in executing oriented flight in a wind tunnel, although their mating success was not affected. We concluded that tebufenozide interferes with various aspects of the reproductive biology of males and females of C. fumiferana and C. rosaceana, including some pre-copulatory behaviors associated with sex pheromone communication. [source] Developmental and spatial covariation of nutrients in growing leaves of Daphne laureola and their relationships with herbivoryNEW PHYTOLOGIST, Issue 3 2003Conchita Alonso Summary , , Here, we studied patterns of covariation of 10 leaf nutrients in expanding and mature leaves of the evergreen shrub Daphne laureola (Thymelaeaceae) in southern Spain. Changes in mean values and covariances of nutrients during leaf development may be relevant for plant fitness through herbivory if variation in leaf nutrients influences plant defoliation. , , We analysed the between-population and developmental covariation of leaf nutrients by using common principal components (CPC) analysis. We also studied the relationships between leaf nutrient covariates and natural levels of plant defoliation. , , Plants at our two study sites shared a CPC structure of covariation between concentrations of the leaf nutrients. Trends of nutrient covariation across individual plants were largely determined by between-plant variations in Ca concentration (CPC1), and by an ,overall nutrient status' gradient (CPC2) that was positively associated with major macronutrients (nitrogen, phosphorus and potassium), in both expanding and mature leaves. , , Plant defoliation was positively related to scores on CPC2 for both expanding and mature leaves, indicating greater consumption on plants with balanced, high concentrations of nitrogen, phosphorus, potassium and calcium. [source] The grain, the wholegrain and nothing but the grain: the science behind wholegrain and the reduced risk of heart disease and cancerNUTRITION BULLETIN, Issue 4 2000David P. Richardson Summary Wholegrain foods are important sources of nutrients and phytoprotective substances that are in short supply in our diet. Encouraging the public to increase consumption of wholegrain foods imparts a positive health message and could contribute towards the achievement of reduced fat and increased fibre intakes. More recent research suggests that the health benefits of wholegrain foods are derived from more than just the fibre. Wholefoods, such as fruit and vegetables and wholegrains, deliver ,packages' of constituents that may work synergistically to promote health. Wholegrain foods, particularly cereals, have been shown to be protective against coronary heart disease, certain cancers and diabetes. At least one daily serving of wholegrain food is associated with reduced risk of disease and there may be further benefits with increasing intake. A greater consumption of wholegrain foods has important public health implications, and would be an attractive and prudent food-based dietary strategy, targeted at the whole population. [source] Role of wild plant foods among late Holocene hunter-gatherers from Central and North Patagonia (South America): An approach from dental evidenceAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2007Valeria Bernal Abstract This study evaluates the role of plant foods in the subsistence of hunter-gatherers that inhabited the Central East, Northwest, and Northeast Patagonia (Argentina) during the late Holocene (ca. 3,000,500 years BP). The goal of the present study is to assess the temporal variation of dental caries ratio and wear rate in skeletal samples to ascertain if the biological information supports the dietary shift toward greater consumption of wild plant foods around 1,500 years BP, suggested by other types of evidence. The authors registered caries, antemortem and postmortem tooth loss, and tooth wear from eight samples belonging to hunter-gatherers from Patagonia for which chronological sequences from early late Holocene (ca. 3,000,1,500 years BP) up to final late Holocene (ca. 1,500,500 years BP) are available. The results indicate that caries percentages in Patagonian samples fall within the range established for hunter-gatherers but there are significant geographical differences. In addition, caries ratio does not change significantly through time, so the amount of carbohydrates consumed seems to have remained fairly constant since 3,000 years BP. In contrast, there is a marked temporal trend toward the reduction of wear rates in the three areas, suggesting a faster rate in early late Holocene than in final late Holocene. These results would reflect a change to less hard and/or abrasive diets in the final late Holocene, probably owing to differences in food processing methods employed. Am J Phys Anthropol, 2007. © 2007 Wiley-Liss, Inc. [source] Tooth wear and dental pathology at the advent of agriculture: New evidence from the LevantAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2006Vered Eshed Abstract Differences in patterns of diet and subsistence through the analysis of dental pathology and tooth wear were studied in skeletal populations of Natufian hunter-gatherers (10,500,8300 BC) and Neolithic populations (8300,5500 BC, noncalibrated) from the southern Levant. 1,160 Natufians and 804 Neolithic teeth were examined for rate of attrition, caries, antemortem tooth loss, calculus, periapical lesions, and periodontal processes. While the Natufian people manifest a higher rate of dental attrition and periodontal disease (36.4% vs. 19%), Neolithic people show a higher rate of calculus. Both populations manifested low and similar rates of caries (6.4% in the Natufian vs. 6.7% in the Neolithic), periapical lesions (not over 1.5%), and antemortem tooth loss (3.7% vs. 4.5%, respectively). Molar wear pattern in the Neolithic is different than in the Natufian. The current study shows that the dental picture obtained from the two populations is multifactorial in nature, and not exclusively of dietary origin, i.e., the higher rate and unique pattern of attrition seen in the Natufian could result from a greater consumption of fibrous plants, the use of pestles and mortars (which introduce large quantities of stone-dust to the food), and/or the use of teeth as a "third hand." The two major conclusions of this study are: 1) The transition from hunting and gathering to a food-producing economy in the Levant did not promote changes in dental health, as previously believed. This generally indicates that the Natufians and Neolithic people of the Levant may have differed in their ecosystem management (i.e., gathering vs. growing grains), but not in the type of food consumed. 2) Changes in food-preparation techniques and nondietary usage of the teeth explain much of the variation in tooth condition in populations before and after the agricultural revolution. Am J Phys Anthropol, 2006. © 2005 Wiley-Liss, Inc. [source] | ||||||||||