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1.
Objective: Eating frequently in restaurants is one of the behaviors associated with obesity. This study examined whether increasing the portion size of an entrée affected energy intake at a restaurant meal. Research Methods and Procedures: In a cafeteria‐style restaurant on different days, the size of a pasta entrée was varied from a standard portion (248 g) to a large portion (377 g). The entrée price was not changed. Intake of the entrée was determined by covertly weighing each dish before and after the meal; intake of all other foods was determined by estimating the percent consumed. The 180 adult customers who purchased the entrée also completed a survey in which they rated characteristics of the meal, including the appropriateness of the entrée portion size and the amount that they ate compared with their usual meal. Results: Portion size had a significant effect on intake of the entrée (p < 0.0001). Compared with customers who purchased the standard portion, those who purchased the larger portion increased their energy intake of the entrée by 43% (719 kJ; 172 kcal) and of the entire meal by 25% (664 kJ; 159 kcal). There was no difference between the two groups of customers in ratings of the appropriateness of the portion size or of the amount that was eaten in relation to their usual meal. Discussion: In a restaurant setting, increasing the size of an entrée results in increased energy intake. These results support the suggestion that large restaurant portions may be contributing to the obesity epidemic.  相似文献   

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Objective: The goal of this study was to evaluate the effect of a parent‐focused behavioral intervention on parent and child eating changes and on percentage of overweight changes in families that contain at least one obese parent and a non‐obese child. Research Methods and Procedures: Families with obese parents and non‐obese children were randomized to groups in which parents were provided a comprehensive behavioral weight‐control program and were encouraged to increase fruit and vegetable intake or decrease intake of high‐fat/high‐sugar foods. Child materials targeted the same dietary changes as their parents without caloric restriction. Results: Changes over 1 year showed that treatment influenced targeted parent and child fruit and vegetable intake and high‐fat/high‐sugar intake, with the Increase Fruit and Vegetable group also decreasing their consumption of high‐fat/high‐sugar foods. Parents in the increased fruit and vegetable group showed significantly greater decreases in percentage of overweight than parents in the decreased high‐fat/high‐sugar group. Discussion: These results suggest that focusing on increasing intake of healthy foods may be a useful approach for nutritional change in obese parents and their children.  相似文献   

4.
Current foraging models limit the decision‐making process of animals to the food searching and consuming phase. The post‐consummatory phase of feeding may influence optimal meal size for some species as a morphologic change often results from feeding. In snakes, a single prey item can lead to abrupt increases in body mass, thus influencing locomotor performance. Identifying factors affecting locomotor performance can help predict behaviors that should maximize an animal's chance of evading predators. Although many snakes ingest large percentages of their body mass, not much work has examined the post‐consummatory effects of ingesting bulky prey differing in relative mass. I examined the locomotor performance and antipredator tactics of hatchling trinket snakes (Elaphe helena) after subjecting snakes to mice prey varying by relative mass differences of 20–35%, 50–59% or 70–79% of an individual hatchling's body mass. Snakes in treatment groups were compared with snakes in a control group (0%). Meal size‐affected locomotor parameters such as burst speed, endurance, and endurance times for hatchlings that ingested 50–59% and 70–79% of their body mass (p < 0.001). Recent feeding also affected the types of antipredator modes employed. Hatchlings in the 0% and 20–35% treatments exhibited behaviors that were categorized as active and threatening, while hatchlings in the 50–59% and 70–79% treatments exhibited stationary, neutral, and cryptic behaviors. Although snakes may become more reclusive following a meal, this study demonstrates that relative prey mass affects the ability of hatchling trinket snakes to flee from a predator. In turn, these results suggest that the post‐consummatory effects of foraging should be considered in optimal foraging models for organisms that consume a substantial portion of their body mass during a single feeding.  相似文献   

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A model is presented for predicting the response of global familydiversity to global environmental change. The model assumesthat three primary mechanisms determine diversity: the capacityto survive the absolute minimum temperature of a site, the abilityto complete the life cycle in a given length and warmth of thegrowing season, and the capacity to expand leaves in a definedregime of precipitation and vegetation transpiration. The directeffects of CO2 on vegetation transpiration are also included. About one-third of the floristic regions of the world exhibitincreased diversity with a 3°C increase in temperature,a 10% increase in precipitation, and a doubling of the CO2 concentration.The addition of CO2 offsets the increased rates of transpiration,caused by global warming through its capacity to reduce transpiration.As a consequence, the diversity of dry regions displayed thegreatest increase in diversity due to increased CO2.  相似文献   

7.
We examined the effects of fruit patch size, density, and distribution on feeding subgroup size and feeding bout duration in four Neotropical primates—Lagothrix lagotricha, Ateles belzebuth, Cebus apella, and Alouatta seniculus—based on 2494 hr of focal animal sampling in Tinigua National Park, Colombia. All four species show positive correlations between patch size (tree diameter at breast height; DBH) and subgroup size (maximum number of individuals from the focal group feeding at the same time), but the determination coefficients are very low and this relationship does not seem to influence strongly the actual size of the groups. Ateles showed the weakest correlation between patch size and feeding party size, and their fission–fusion sociality is best explained as a mechanism to reduce intragroup competition rather than to adjust the subgroup size to the availability of patches. Feeding associations as well as proximal spacing patterns, in general, are more alike in species with similar ecological requirements.  相似文献   

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BackgroundLow fruit and vegetable (FV) intake is a leading risk factor for chronic disease globally as well as in the United States. Much of the population does not consume the recommended servings of FV daily. This paper describes the development of psychosocial measures of FV intake for inclusion in the U.S. National Cancer Institute’s 2007 Food Attitudes and Behaviors Survey.MethodsThis was a cross-sectional study among 3,397 adults from the United States.Scales included conventional constructs shown to be correlated with fruit and vegetable intake (FVI) in prior studies (e.g., self-efficacy, social support), and novel constructs that have been measured in few- to- no studies (e.g., views on vegetarianism, neophobia). FVI was assessed with an eight-item screener. Exploratory factor analysis, Cronbach’s alpha, and regression analyses were conducted.ResultsPsychosocial scales with Cronbach’s alpha ≥0.68 were self-efficacy, social support, perceived barriers and benefits of eating FVs, views on vegetarianism, autonomous and controlled motivation, and preference for FVs. Conventional scales that were associated (p<0.05) with FVI were self-efficacy, social support, and perceived barriers to eating FVs. Novel scales that were associated (p<0.05) with FVI were autonomous motivation, and preference for vegetables. Other single items that were associated (p<0.05) with FVI included knowledge of FV recommendations, FVI “while growing up”, and daily water consumption.ConclusionThese findings may inform future behavioral interventions as well as further exploration of other potential factors to promote and support FVI.  相似文献   

10.
Brazil has one of the fastest aging populations in the world and the incidence of cognitive impairment in the elderly is expected to increase exponentially. We examined the association between cognitive impairment and fruit and vegetable intake and associated factors in a low-income elderly population. A cross-sectional population-based study was carried out with 1849 individuals aged 65 or over living in São Paulo, Brazil. Cognitive function was assessed using the Community Screening Instrument for Dementia (CSI-D). Fruit and vegetable intake was assessed with a Food Frequency Questionnaire (FFQ) and categorized into quartiles of intake and into total daily fruit and vegetable intake using the cut-off points for the WHO recommendations (<400grams/day or ≥400 grams/day). The association between cognitive impairment and each quartile of intake, and WHO recommendation levels, was evaluated in two separate multivariate logistic models. The WHO recommendations for daily intakes ≥400 grams/day were significantly associated with 47% decreased prevalence of cognitive impairment. An effect modification was found in both models between cognitive impairment and “years of education and physical activity” and “years of education and blood levels of HDL” So that, having 1 or more years of education and being physically active or having 1 or more years of education and levels higher than 50 mg/dl of HDL-cholesterol strongly decreased the prevalence of cognitive impairment. In this socially deprived population with very low levels of education and physical activity and fruit and vegetable intake, those who attained WHO recommendations, had 1 year or more of education and were physically active had a significantly lower prevalence of cognitive impairment. A more comprehensive understanding of the social determinants of mental health is needed to develop effective public policies in developing countries.  相似文献   

11.

Background

Whey proteins have insulinogenic properties and the effect appears to originate from a specific postprandial plasma amino acid pattern. The insulinogenic effect can be mimicked by a specific mixture of the five amino acids iso, leu, lys, thr and val.

Objective

The objective was to evaluate the efficacy of pre-meal boluses of whey or soy protein with or without added amino acids on glycaemia, insulinemia as well as on plasma responses of incretins and amino acids at a subsequent composite meal. Additionally, plasma ghrelin and subjective appetite responses were studied.

Design

In randomized order, fourteen healthy volunteers were served a standardized composite ham sandwich meal with either water provided (250 ml) during the time course of the meal, or different pre-meal protein drinks (PMPD) (100 ml provided as a bolus) with additional water (150 ml) served to the meal. The PMPDs contained 9 g protein and were based on either whey or soy protein isolates, with or without addition of the five amino acids (iso, leu, lys, thr and val) or the five amino acids + arg.

Results

All PMPD meals significantly reduced incremental area for plasma glucose response (iAUC) during the first 60 min. All whey based PMPD meals displayed lower glycemic indices compared to the reference meal. There were no significant differences for the insulinemic indices. The early insulin response (iAUC 0–15 min) correlated positively to plasma amino acids, GIP and GLP-1 as well as to the glycemic profile. Additionally, inverse correlations were found between insulin iAUC 0–15 min and the glucose peak.

Conclusion

The data suggests that a pre-meal drink containing specific proteins/amino acids significantly reduces postprandial glycemia following a composite meal, in absence of elevated insulinemic excursions. An early phase insulinemic response induced by plasma amino acids and incretins appears to mediate the effect.

Trial Registration

ClinicalTrials.gov NCT01586780<NCT01586780>  相似文献   

12.
根据果蔬多孔质特点,建立了热风、远红外和微波干燥果蔬过程中同时考虑温度、水分影响的内部质热传递模型.并进行理论计算和实测比较.热风干燥时温度水分和微波干燥时水分的模拟值与实测值十分接近;微波干燥时的物料温度和远红外干燥时的温度水分模拟值与实测值略有差异.分析了产生差异的原因.  相似文献   

13.
BANGERTH  F.; HO  L. C. 《Annals of botany》1984,53(3):315-320
The position of fruits in a truss and the induction sequenceof fruit set has been examined for the effects on the finalsize of parthenocarpic fruits in tomato. Fruits at two developmentalstages were examined to measure the change of d. wt and theimport of 14C leaf assimilates. The sequence of induction largely determined the import rateinto fruits of the same truss and first-induced fruits are thereforelarger within the same truss. The position of fruits in thetruss modifies the extent of this ‘primigen dominance’effect. Possible mechanisms for this dominance phenomenon arediscussed. Position, set sequence, size, fruit, Lycopersicon esculentum Mill  相似文献   

14.
Catalase activity and induction of delayed chlorophyll fluorescence were shown to be the markers of the plant native state. The dependence of reaction of the plant to exogenous elicitors, stimulators or inhibitors of the defense system, on the age, cultivar and/or species was found. Prolonged effect of the treatment with phytoimmunocorrectors was observed. The necessity of careful choice of elicitors depending on the plant state was shown.  相似文献   

15.
The reversible inhibition of three ripening-related processes by high-temperature treatment (38[deg]C) was examined in tomato (Lycopersicon esculentum L. cv Daniella) fruit. Ethylene production, color development, and softening were inhibited during heating and recovered afterward, whether recovery took place at 20[deg]C or fruit were first held at chilling temperature (2[deg]C) after heating and then placed at 20[deg]C. Ethylene production and color development proceeded normally in heated fruit after 14 d of chilling, whereas the unheated fruit had delayed ethylene production and uneven color development. Levels of mRNA for 1-aminocyclopropane-1-carboxylic acid oxidase, phytoene synthase, and polygalacturonase decreased dramatically during the heat treatment but recovered afterward, whereas the mRNA for HSP17 increased during the high-temperature treatment and then decreased when fruit were removed from heat. As monitored by western blots, the HSP17 protein disappeared from fruit tissue after 3 d at 20[deg]C but remained when fruit were held at 2[deg]C. The persistence of heat-shock proteins at low temperature may be relevant to the protection against chilling injury provided by the heat treatment. Protein levels of 1-aminocyclopropane-1-carboxylic acid oxidase and polygalacturonase also did not closely follow the changes in their respective mRNAs. This implied both differences in relative stability and turnover rates of mRNA compared to protein and nontranslation of the message that accumulated in low temperature. The results suggest that high temperature inhibits ripening by inhibiting the accumulation of ripening-related mRNAs. Ripening processes that depend on continuous protein synthesis including ethylene production, lycopene accumulation, and cell-wall dissolution are thereby diminished.  相似文献   

16.
《Anthrozo?s》2013,26(1):21-35
ABSTRACT

Having pets at home provides various social, health, and educational benefits to children. The question of how keeping pets at home affects the attitudes of children toward wild animals still has not been answered, due to various methodological issues, such as ignorance of some attitude dimensions and/or questionnaires that include items focused on very different animals. We conducted three independent research surveys (using three independent samples) of Slovakian primary school children aged 10 to 15 years (n = 1297). These surveys focused on the effects of keeping pets on the attitudes of children towards, and knowledge of, three unpopular animals in Slovakia. These animals were pests (potato beetle) (Study 1), predators (wolf) (Study 2), and those that pose a threat of disease to humans (mouse) (Study 3). Each survey also included a popular animal (ladybird beetle, rabbit, and squirrel, respectively), which served as a “control”; these were compared by pair-wise statistics. Results consistently showed that children had better knowledge of, but less favorable attitudes towards, unpopular animals compared with popular ones. Having pets at home was associated with more positive attitudes to, and better knowledge of, both popular and unpopular animals. Girls were less favorably inclined than boys to animals that may pose a threat, danger, or disease to them. Implications for humane education are discussed, especially in terms of keeping pets, the link between knowledge and attitudes, and children's understanding of ecological adaptations.  相似文献   

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Studies of zoochorous seed dispersal systems often consider crop size, yet seldom consider the kinds and amounts of fruits surrounding parent plants (the fruit neighborhood) when attempting to explain among‐plant variation in fruit removal. We studied avian frugivory at 24 Schefflera morototoni trees from February to May 1998 in central Puerto Rico. The number of fruits removed by avian seed dispersers per visit was similar among focal trees (typically 2–4). In contrast, visitation rate was highly variable (range: 0–71 visits per 4 h). We used multiple regression analyses to evaluate the relative roles of crop size (focal tree ripe fruit abundance) and fruit neighborhood variables (measured within 30 m of focal trees) in affecting visitation to focal trees by avian frugivores. Visitation rate was positively related to crop size (although this variable was only significant in one of four regression models considered) and negatively related to the presence or abundance of conspecific fruits, suggesting that trees competed intraspecifically for dispersers. Relationships between visitation and heterospecific fruits were mixed—some kinds of fruits appeared to enhance visitation to focal trees, while others seemed to reduce visitation. In most regression models, neighborhood variables had larger effects on visitation than focal tree fruit crop size. Our results highlight the important effects of local fruiting environments on the ability of individual plants to attract seed dispersers.  相似文献   

19.

Introduction

A reduction in homocysteine concentration due to the use of supplemental folic acid is well recognized, although evidence of the same effect for natural folate sources, such as fruits and vegetables (FV), is lacking. The traditional statistical analysis approaches do not provide further information. As an alternative, quantile regression allows for the exploration of the effects of covariates through percentiles of the conditional distribution of the dependent variable.

Objective

To investigate how the associations of FV intake with plasma total homocysteine (tHcy) differ through percentiles in the distribution using quantile regression.

Materials and Methods

A cross-sectional population-based survey was conducted among 499 residents of Sao Paulo City, Brazil. The participants provided food intake and fasting blood samples. Fruit and vegetable intake was predicted by adjusting for day-to-day variation using a proper measurement error model. We performed a quantile regression to verify the association between tHcy and the predicted FV intake. The predicted values of tHcy for each percentile model were calculated considering an increase of 200 g in the FV intake for each percentile.

Results

The results showed that tHcy was inversely associated with FV intake when assessed by linear regression whereas, the association was different when using quantile regression. The relationship with FV consumption was inverse and significant for almost all percentiles of tHcy. The coefficients increased as the percentile of tHcy increased. A simulated increase of 200 g in the FV intake could decrease the tHcy levels in the overall percentiles, but the higher percentiles of tHcy benefited more.

Conclusions

This study confirms that the effect of FV intake on lowering the tHcy levels is dependent on the level of tHcy using an innovative statistical approach. From a public health point of view, encouraging people to increase FV intake would benefit people with high levels of tHcy.  相似文献   

20.
Egg-Mass Size and Cell Size: Effects of Temperature on Oxygen Distribution   总被引:4,自引:3,他引:1  
Two processes strongly influence the distribution of oxygenwithin egg masses and cells: the supply of oxygen by diffusionand the consumption of oxygen by embryos and mitochondria. Theseprocesses are differentially sensitive to temperature. The diffusioncoefficient of oxygen depends only weakly on temperature, havinga Q10 of approximately 1.4. In contrast, the consumption ofoxygen depends strongly on temperature, having a Q10 between1.5 and 4.0. Thus, at higher temperatures, the ratio of oxygensupply to demand decreases. I show, by extending a model ofoxygen distribution within metabolizing spheres, that maximalegg-mass sizes and cell sizes are predicted to be smaller athigher temperatures. For egg masses, definitive data are notyet available. For ectothermic cells, this prediction appearsto be supported; cells from a variety of ectothermic organisms,unicellular and multicellular, are smaller when the cells areproduced at warmer temperatures. Establishing a specific connectionbetween this pattern and oxygen distributions requires demonstrationof (1) oxygen concentration gradients within metabolizing spheresand (2) central oxygen concentrations low enough to affect function.Egg masses from a variety of taxa show steep oxygen concentrationgradients and often are severely hypoxic or anoxic in centrallocations. Severe hypoxia appears capable of retarding developmentor killing embryos. Similar kinds of data for ectothermic cellshave not yet been collected, but the literature on oxygen gradientswithin mammalian cells suggests that intracellular gradientsmay be important.  相似文献   

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