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Results 251 - 300 of 347
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Müller Claudia E - - 2011
The biomagnification behavior of perfluorinated carboxylates (PFCAs) and perfluorinated sulfonates (PFSAs) was studied in terrestrial food webs consisting of lichen and plants, caribou, and wolves from two remote northern areas in Canada. Six PFCAs with eight to thirteen carbons and perfluorooctane sulfonate (PFOS) were regularly detected in all species. Lowest ...
Chiu Grace S - - 2011
A food web consists of nodes, each consisting of one or more species. The role of each node as predator or prey determines the trophic relations that weave the web. Much effort in trophic food web research is given to understand the connectivity structure, or the nature and degree of ...
Qureshi Naema - - 2011
Although studies have yet to prove definitively a causal relationship between diet and acne, the lay public has traditionally held that such causality exists. The authors' study aims to determine which nutritional elements are thought to be related to acne, both positively and negatively. YouTube, a popular video-sharing Web site, ...
Baillie Jonathan - - 2011
An independent survey into hospital food standards in England conducted earlier this year for the Soil Association saw over half of those patients surveyed admit they would not be happy serving the meals they received during a recent hospital stay to a child, while 29% said the food was so ...
Abrams Peter A - - 2011
Abstract This article analyzes the nature of top-down and bottom-up effects and alternative states in systems characterized by life-history omnivory. The analysis is based on a three-species food web with intraguild predation (IGP). The top predator population has juvenile and adult stages, which consume the basal resource and the intermediate ...
Goodman Samantha - - 2011
To examine longitudinal trends in use of nutrition information among Canadians. Population-based telephone and Internet surveys. Representative samples of Canadian adults recruited with random-digit dialing sampling in 2004 (n = 2,405) and 2006 (n = 2,014) and an online commercial panel in 2008 (n = 2,001). Sociodemographic predictors of label ...
Williams Richard J - - 2011
The structure of food webs, complex networks of interspecies feeding interactions, plays a crucial role in ecosystem resilience and function, and understanding food web structure remains a central problem in ecology. Previous studies have shown that key features of empirical food webs can be reproduced by low-dimensional "niche" models. Here ...
Cross Wyatt F - - 2011
Large dams have been constructed on rivers to meet human demands for water, electricity, navigation, and recreation. As a consequence, flow and temperature regimes have been altered, strongly affecting river food webs and ecosystem processes. Experimental high-flow dam releases, i.e., controlled floods, have been implemented on the Colorado River, U.S.A., ...
Skatrud-Mickelson Monica M Department of Pediatrics, Dartmouth Medical School, Lebanon, NH 03756, - - 2011
Television viewing is associated with an increased risk in childhood obesity. Research surrounding food habits of tweens largely bypasses snacking preferences while watching television in the home. The aim of this cross-sectional study was to describe snacking prevalence by tween sex and to describe parental rules surrounding snacking while watching ...
Nevitt Gabrielle A - - 2011
Information transfer influences food-web dynamics in the marine environment, but infochemicals involved in these processes are only beginning to be understood. Dimethylsulfoniopropionate (DMSP) is produced by phytoplankton and other marine algae, and has been studied primarily in the context of sulfur cycling and regulation of global climate. My laboratory has ...
Di Beneditto Ana Paula Madeira - - 2011
The present study raised the hypothesis that the trophic status in a tropical coastal food web from southeastern Brazil can be measured by the relation between total mercury (THg) and nitrogen isotope (δ(15)N) in their components. The analysed species were grouped into six trophic positions: primary producer (phytoplankton), primary consumer ...
Harris Jennifer L - - 2011
The obesity epidemic cannot be reversed without substantial improvements in the food marketing environment that surrounds children. Food marketing targeted to children almost exclusively promotes calorie-dense, nutrient-poor foods and takes advantage of children's vulnerability to persuasive messages. Increasing scientific evidence reveals potentially profound effects of food marketing on children's lifelong ...
Zižek Suzana - - 2011
Mercury presents a potential risk to the environment and humans, especially in its methylated form. It is among the highest priority environmental pollutants. River Idrijca (Slovenia) is highly contaminated with mercury due to past mercury mining. The aim of this work was to investigate whether the periphyton community in rivers ...
Arias-González Jesús Ernesto - - 2011
The invasion of lionfish in the Caribbean is causing grave concern because of its deleterious impacts on coral reef food-webs. We have used an Ecopath-with-Ecosim model to predict the impacts of lionfish invasion on a coral reef community based on pre-invasion fish community data. Forty-six groups were defined, and an ...
Jassey Vincent E J - - 2011
Population dynamics and feeding habits of the testate amoebae Nebela tincta and Hyalosphenia papilio were studied along a short "fen" to "bog" gradient in a Sphagnum-dominated mire (Jura, France). Samples were collected in living "top segments" (0-3cm) and early declining "bottom segments" (3-6cm) of Sphagnum fallax peat. Observations of digestive ...
Wurtsbaugh Wayne A - - 2011
The Great Salt Lake has a salinity near 150g/L and is habitat for over 200 species of migratory birds. The diet of many of these birds is dependent on the food web of carbonaceous biostromes (stromatolites) that cover 260km(2) of the lake's littoral zone. We investigated the biostrome community to ...
Kaschula Sarah - - 2011
Household afflicted by HIV/AIDS are particularly prone to food insecurity. This article explores the role of community networks in meeting household food deficits. One hundred households exhibiting a range (0-5) of HIV/AIDS proxies related to orphan fostering, prime adult chronic illness and mortality were visited at quarterly intervals for a ...
Médoc Vincent - - 2011
Although trophically transmitted parasites are recognized to strongly influence food-web dynamics through their ability to manipulate host phenotype, our knowledge of their host spectrum is often imperfect. This is particularly true for the facultative paratenic hosts, which receive little interest. We investigated the occurrence and significance both in terms of ...
Gravel Dominique - - 2011
Ecology Letters (2011) ABSTRACT: MacArthur and Wilson's Theory of Island Biogeography (TIB) is among the most well-known process-based explanations for the distribution of species richness. It helps understand the species-area relationship, a fundamental pattern in ecology and an essential tool for conservation. The classic TIB does not, however, account for ...
Matuszak Anja - - 2011
Macrophytes are at the base of many lake food webs providing essential food resources for animals at higher trophic level, such as invertebrates, fish and waterbirds. However, data regarding the spatiotemporal variation in isotopic composition of macrophytes are generally missing. We measured the carbon and nitrogen stable isotope ratios of ...
Frank Kenneth T - - 2011
Overfishing of large-bodied benthic fishes and their subsequent population collapses on the Scotian Shelf of Canada's east coast and elsewhere resulted in restructuring of entire food webs now dominated by planktivorous, forage fish species and macroinvertebrates. Despite the imposition of strict management measures in force since the early 1990s, the ...
Wimp Gina M - - 2011
Ecology Letters (2011) ABSTRACT: Despite nearly 100 years of edge studies, there has been little effort to document how edge responses 'cascade' to impact multi-trophic food webs. We examined changes within two, four-tiered food webs located on opposite sides of a habitat edge. Based on a 'bottom-up' resource-based model, we predicted ...
Smith Anthony D M - - 2011
Low-trophic level species account for more than 30% of global fisheries production and contribute substantially to global food security. We used a range of ecosystem models to explore the effects of fishing low-trophic level species on marine ecosystems, including marine mammals and seabirds, and on other commercially important species. In ...
Tinnemann Peter - - 2011
BACKGROUND: The socio-economic gap and its associated health inequalities are increasing in Germany. Actions against poverty include the redistribution of foods through charities. One project supported by the main German food redistribution charity is offering fresh produce including mostly fruits, vegetables and bread to people receiving welfare in Berlin, Germany. ...
Bernstad Anna - - 2011
A system with property-close source-separation of thirteen different solid household waste fractions in a residential area in southern Sweden, including the implementation of new systems for source-separation of food waste, waste electric and electronic equipment, hazardous waste and fat, oils and grease was monitored over a 2-year period. Continuous weighing ...
Rolfhus Kristofer R - - 2011
While mercury is a health hazard to humans and wildlife, the biogeochemical processes responsible for its bioaccumulation in pelagic food webs are still being examined. Previous studies have indicated both "bottom-up" control of piscivorous fish Hg content through methylmercury.(MeHg) supply, as well as site-specific trophic factors. We evaluated ten studies ...
Kim Joon-Woo - - 2011
Benzotriazole ultraviolet stabilizers (BUVSs) used in plastic products, building materials and personal hygiene products were analyzed in fishes collected from Manila Bay, the Philippines. BUVSs were detected at ngg(-1) level in all the fish samples, indicating their ubiquitous contamination in coastal waters. Among the targeted eight BUVSs, UV-328 was predominantly ...
Langiano Elisa - - 2012
AIM: To define food safety and risk perception of foodborne diseases in the private home setting and identify specific behaviours during food purchase, storage and preparation in a large survey study. SUBJECT AND METHODS: A large sample of individuals (n = 1,000) living in the area of Cassino, Italy, volunteered to participate ...
García-Segovia P - - 2011
The food frequency questionnaires are widely used in epidemiological researches like dietary assessment method. Traditionally, they have been self-administered in paper but the use of information and communication technologies has led to develop Internet and computerized food frequency questionnaires. It is the objective of this article to offer a global ...
Pretlow Robert A - - 2011
An interactive, open-access website was launched as an overweight intervention for teens and preteens, and was generally unsuccessful. An understanding was needed of the reasons for weight loss failures versus successes in youth using the site. Bulletin board posts, chat room transcripts, and poll responses were prospectively gathered and qualitatively ...
Brooks Kathleen R - - 2011
In January 2008, the United States Food and Drug Administration concluded "meat and milk from cattle, swine, and goat clones or their offspring are as safe to eat as food we eat from those species now" (U.S. FDA, 2010). However, cloning remains a very controversial topic. A web-based survey administered ...
Aizaki Hideo - - 2011
Novel food technologies, such as cloning, have been introduced into the meat production sector; however, their use is not widely supported by many consumers. This study was designed to assess whether Japanese consumers' attitudes toward consumption of cloned beef (specifically, beef derived from bovine embryo and somatic cell-cloned cattle) would ...
Conley J M - - 2011
Selenium effects in nature are mediated by the relatively large bioconcentration of aqueous Se by primary producers and smaller, yet critical, dietary transfers to primary consumers. These basal processes are then propagated through food webs to higher trophic levels. Here we quantified the movement of dissolved Se (as selenite) to ...
Lebersorger S - - 2011
Food waste has become an increasingly discussed topic in recent years. However, there is little authoritative data on food waste quantities and composition and systematic and comparable data are missing. Household waste composition analyses, which are often carried out routinely at regular or irregular intervals, provide an opportunity for obtaining ...
Tsui Martin Tsz Ki - - 2011
Stream ecosystems are widely contaminated by mercury (Hg) via atmospheric transport and deposition in watersheds. Dissolved organic carbon (DOC) is well-known to be the dominant ligand for aqueous methylmercury (MeHg), the bioaccumulative form of Hg in aquatic food webs. However, it is less clear if and how the concentration and ...
St Louis Vincent L - - 2011
Polar bears (Ursus maritimus) are being impacted by climate change and increased exposure to pollutants throughout their northern circumpolar range. In this study, we quantified concentrations of total mercury (THg) in the hair of polar bears from Canadian high- (southern Beaufort Sea, SBS) and sub- (western Hudson Bay, WHB) Arctic ...
Borgå Katrine - - 2011
Recent reviews by researchers from academia, industry and government have revealed that the criteria used by the Stockholm Convention on persistent organic pollutants (POPs) under the United Nations Environmental Programme are not always able to identify the actual bioaccumulative capacity of some substances using chemical properties such as octanol-water partitioning ...
Bastidas Navarro Marcela - - 2011
Mixotrophic nanoflagellates, that combine photosynthesis and phagotrophy, are important members of planktonic food webs in many aquatic environments depending on the balance among the different carbon and energy sources. We carried out field sampling and laboratory experiments with natural nanoflagellate assemblages from an Andean North-Patagonian lake exposing them or not ...
Carrasco Luis - - 2011
The low Ebro River basin (NE Spain) represents a particular case of chronic and long-term mercury pollution due to the presence of an industrial waste (up to 436μg/g of Hg) coming from a chlor-alkali plant Albeit high total mercury (THg) levels have been previously described in several aquatic species from ...
Loi Eva I H - - 2011
Perfluorinated compounds (PFCs) are known to biomagnify in temperate and Arctic food webs, but little is known about their behavior in subtropical systems. The environmental distribution and biomagnification of PFCs, extractable organic fluorine (EOF), and total fluorine were investigated in a subtropical food web. Surface water, sediment, phytoplankton, zooplankton, gastropods, ...
Condon Robert H - - 2011
Jellyfish blooms occur in many estuarine and coastal regions and may be increasing in their magnitude and extent worldwide. Voracious jellyfish predation impacts food webs by converting large quantities of carbon (C), fixed by primary producers and consumed by secondary producers, into gelatinous biomass, which restricts C transfer to higher ...
Drenner Ray W - - 2011
Mercury (Hg) is a toxic metal that is found in aquatic food webs and is hazardous to humans. An emerging conceptual model predicts that the areas of the landscape that have the potential to contain food webs with elevated concentrations of Hg are those that receive high amounts of Hg ...
De Laender F - - 2011
An extensive data set describing effects of the herbicide linuron on macrophyte-dominated microcosms was analysed with a food web model to assess effects on ecosystem functioning. We showed that sensitive phytoplankton and periphyton groups in the diets of heterotrophs were gradually replaced by more tolerant phytoplankton species as linuron concentrations ...
Dennisuk Lauren A - - 2011
Low-income, urban African-American youth are at higher risk for obesity and less likely to meet dietary recommendations than white, higher-income youth. Patterns of food purchasing among youth likely contribute to these disparities, but little published information is available. To investigate food purchasing behaviors of low-income, urban African-American youth. A total ...
Marcarelli Amy M - - 2011
Although the study of resource subsidies has emerged as a key topic in both ecosystem and food web ecology, the dialogue over their role has been limited by separate approaches that emphasize either subsidy quantity or quality. Considering quantity and quality together may provide a simple, but previously unexplored, framework ...
Hall Carrie L - - 2011
Competition between scavengers and microorganisms for the nutrients within carrion is well documented. As a significant contributor to food web energetics, carrion serves not only as a food source for scavengers, but also as a reproductive resource for many insects. One example are the burying beetles of the Nicrophorus genus ...
Rochet M-J - - 2012
Fishing impacts on marine food webs are predicted by simulations of a size spectrum community model. In this model, predation is determined by predator and prey size and abundance, and drives predator growth and prey mortality. Fishing amplifies temporal oscillations in the biomass flow. Oscillations appear at lower fishing intensity ...
Massana Ramon - - 2011
The eukaryotic picoplankton is a heterogeneous collection of small protists 1 to 3 µm in size populating surface oceans at abundances of 10(2) to 10(4) cells ml(-1). Pigmented cells are important primary producers that are at the base of food webs. Colorless cells are mostly bacterivores and play key roles ...
Behera Shishir Kumar - - 2011
The current food waste leachate (FWL) disposal practice in Korea warrants urgent attention and necessary action to develop an innovative and sustainable disposal strategy, which is both environmentally friendly and economically beneficial. In this study, methane production by FWL injection into a municipal solid waste landfill with landfill gas (LFG) ...
Yu Le-Huan - - 2011
As an important group of brominated flame retardants, polybrominated diphenyl ethers (PBDEs) persist in the wildlife food webs. However, the biomagnification of PBDEs has not been adequately studied in the terrestrial food webs. In this study, a terrestrial food web composed of common kestrels, sparrows, rats, grasshoppers, and dragonflies in ...
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