9,370 research outputs found
Implications of "peak oil" for atmospheric CO2 and climate
Unconstrained CO2 emission from fossil fuel burning has been the dominant
cause of observed anthropogenic global warming. The amounts of "proven" and
potential fossil fuel reserves are uncertain and debated. Regardless of the
true values, society has flexibility in the degree to which it chooses to
exploit these reserves, especially unconventional fossil fuels and those
located in extreme or pristine environments. If conventional oil production
peaks within the next few decades, it may have a large effect on future
atmospheric CO2 and climate change, depending upon subsequent energy choices.
Assuming that proven oil and gas reserves do not greatly exceed estimates of
the Energy Information Administration, and recent trends are toward lower
estimates, we show that it is feasible to keep atmospheric CO2 from exceeding
about 450 ppm by 2100, provided that emissions from coal, unconventional fossil
fuels, and land use are constrained. Coal-fired power plants without
sequestration must be phased out before mid-century to achieve this CO2 limit.
It is also important to "stretch" conventional oil reserves via energy
conservation and efficiency, thus averting strong pressures to extract liquid
fuels from coal or unconventional fossil fuels while clean technologies are
being developed for the era "beyond fossil fuels". We argue that a rising price
on carbon emissions is needed to discourage conversion of the vast fossil
resources into usable reserves, and to keep CO2 beneath the 450 ppm ceiling.Comment: (22 pages, 7 figures; final version accepted by Global Biogeochemical
Cycles
Benefit-Cost Meta-Analysis of Investment in the International Agricultural Research Centers of the CGIAR
This study was undertaken by David Raitzer, on behalf of the CGIAR Standing Panel on Impact Assessment. The author addresses the question: do the documented benefits from CGIAR research justify the total investment in the CGIAR so far? The basic objective of the study is to derive a set of plausible and highly credible aggregate estimates of the benefits accruing from System innovations, and to set such against the present value of the entire CGIAR expenditure. The study contains several figures and tables. The forward was written by Hans Gregersen, Chair of the Standing Panel on Impact Assessment
Going beyond defining: Preschool educators\u27 use of knowledge in their pedagogical reasoning about vocabulary instruction
Previous research investigating both the knowledge of early childhood educators and the support for vocabulary development present in early childhood settings has indicated that both educator knowledge and enacted practice are less than optimal, which has grave implications for children\u27s early vocabulary learning and later reading achievement. Further, the nature of the relationship between educators\u27 knowledge and practice is unclear, making it difficult to discern the best path towards improved knowledge, practice, and children\u27s vocabulary outcomes. The purpose of the present study was to add to the existing literature by using stimulated recall interviews and a grounded approach to examine how 10 preschool educators used their knowledge to made decisions about their moment-to-moment instruction in support of children\u27s vocabulary development. Results indicate that educators were thinking in highly context-specific ways about their goals and strategies for supporting vocabulary learning, taking into account important knowledge of their instructional history with children and of the children themselves to inform their decision making in the moment. In addition, they reported thinking about research-based goals and strategies for supporting vocabulary learning that went beyond simply defining words for children. Implications for research and professional development are discussed
Safety of phenylcapsaicin as a novel food pursuant to Regulation (EU) 2015/2283
Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on phenylcapsaicin as a novel food (NF) pursuant to Regulation (EU) 2015/2283. Phenylcapsaicin is a chemically synthesised analogue of capsaicin intended to be marketed in food supplements and in foods for special medical purposes to the general population above the age of 11 years old at a maximum level of 2.5 mg/day. The highest intake of the NF is 2.5 mg/day which corresponds to 36 mu g/kg body weight (bw) per day for adults, and 58 mu g/kg bw per day for adolescents (10-14 years). The Panel considers that there is no concern with respect to genotoxicity of the NF. The reference point derived based on a 13-week rat study was the lowest of the model averaged BMDL20 values of 37.2 mg/kg bw per day in females for increased plasma alanine aminotransferase (ALAT) levels. The Panel concludes that the NF, phenylcapsaicin, is safe under the proposed uses and use levels. (C) 2019 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.Peer reviewe
EPUAP classification system for pressure ulcers: European reliability study
‘The definitive version is available at www3.interscience.wiley.com .' Copyright Blackwell PublishingPeer reviewe
From uniformity to diversity: a paradigm shift from industrial agriculture to diversified agroecological systems
Today’s food and farming systems have succeeded in supplying large volumes of foods to global markets, but are generating negative outcomes on multiple fronts: widespread degradation of land, water and ecosystems; high GHG emissions; biodiversity losses; persistent hunger and micro-nutrient deficiencies alongside the rapid rise of obesity and diet-related diseases; and livelihood stresses for farmers around the world. Many of these problems are linked specifically to ‘industrial agriculture’: the input-intensive crop monocultures and industrial-scale feedlots that now dominate farming landscapes. The uniformity at the heart of these systems, and their reliance on chemical fertilizers, pesticides and preventive use of antibiotics, leads systematically to negative outcomes and vulnerabilities. What is required is a fundamentally different model of agriculture based on diversifying farms and farming landscapes, replacing chemical inputs, optimizing biodiversity and stimulating interactions between different species, as part of holistic strategies to build long-term fertility, healthy agro-ecosystems and secure livelihoods, i.e. ‘diversified agroecological systems’
Safety of frozen and dried formulations from whole yellow mealworm (Tenebrio molitor larva) as a novel food pursuant to Regulation (EU) 2015/2283
Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on frozen and dried formulations from whole yellow mealworm (Tenebrio molitor larva) as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The term yellow mealworm refers to the larval form of the insect species Tenebrio molitor. The NF comprises the frozen and freeze-dried formulations of the yellow mealworm, whole or in the form of powder. The frozen formulation consists mainly of water, crude protein and fat whereas the freeze-dried formulations of crude protein, fat, digestible carbohydrates and fibre (chitin). The Panel notes that the levels of contaminants in the NF depend on the occurrence levels of these substances in the insect feed. The Panel notes furthermore that there are no safety concerns regarding the stability of the NF if the NF complies with the proposed specification limits during its entire shelf-life. The dried formulations of the NF have a high protein content, although the true protein levels in the NF are overestimated when using the nitrogen-to-protein conversion factor of 6.25, due to the presence of non-protein nitrogen from chitin. The applicant proposed to use the NF as whole frozen or whole dried insect, or in the form of powder, added as an ingredient to various food products such as cereal bars, pasta, meat imitates and bakery products. The target population is the general population. The Panel notes that, considering that the NF will not be the sole source of dietary protein, and the composition of the NF and the proposed conditions of use, the consumption of the NF is not nutritionally disadvantageous. The submitted toxicity studies from the literature did not raise safety concerns. The Panel considers that the consumption of the NF may induce primary sensitisation and allergic reactions to yellow mealworm proteins and may cause allergic reactions in subjects with allergy to crustaceans and dust mites. Additionally, allergens from the feed may end up in the NF. The Panel concludes that the NF is safe under the proposed uses and use levels. (C) 2021 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.Peer reviewe
Safety of hot water extract of fruits and peduncles of Hovenia dulcis as a novel food pursuant to Regulation 1(EU) 2015/2283
Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on the safety of 'Hovenia dulcis fruit extract' as a novel food (NF) for its use in food supplements. The NF concerns a hot water extract of sliced and dried fruits and peduncles of Hovenia dulcis Thun. The production process is described in sufficient detail but contains contradictory information regarding the mixing with another ingredient of the NF. The NF is comprised of mostly carbohydrates (about 90%), about 2% proteins, 5% moisture, less than 1% fat and about 2% ash. In addition, the NF contains small amounts of flavonoids such as dihydromyricetin, myricetin and quercetin. The Panel notes limitations of the data provided from the batch testing regarding proximate analyses and plant secondary metabolites. Given these limitations, the Panel considers that the data provided by the applicant do not demonstrate that different batches produced with the described production process meet the proposed specifications. The target population is the general adult population excluding pregnant and lactating women and people with a chronic disease, such as liver malfunction. Limited information was provided on a history of consumption of Hovenia dulcis fruits and on an extract approved in South Korea. A number of toxicological studies were performed. However, the study reports did not allow to verify that the test item was representative of the NF. The same applied to a human study provided by the applicant. The Panel concludes that the safety of the NF has not been established. (c) 2020 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.Non peer reviewe
Safety of viable embryonated eggs of the whipworm Trichuris suis as a novel food pursuant to Regulation (EU) 2015/2283
Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on viable embryonated eggs of the whipworm Trichuris suis as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The applicant proposes to use the NF as a food supplement in the format of a 15-mL bottle containing 250 viable embryonated eggs of T. suis. The target population for the NF is the general population. Considering the compositional data and proposed conditions of use, the consumption of the NF is considered of no nutritional relevance. Available data suggest that most larvae of T. suis after hatching in the intestinal tract of humans remain immature and live for several weeks in the gastrointestinal tract of the human host. Nevertheless, under certain circumstances, T. suis can be invasive in human, being able to mature into adult size and reproduce in humans. Human studies have also shown that administration of T. suis ova may increase the incidence of adverse gastrointestinal reactions. The Panel considers that there are no studies available that demonstrate the safety of this NF intended for the general population at a proposed intake of 250 viable embryonated eggs of T. suis ova per day. Based on the available information, the Panel cannot establish a safe dose at which no safety concerns would be expected. The Panel concludes that the safety of the NF has not been established. (C) 2019 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.Peer reviewe
Safety of 2 '-fucosyllactose/difucosyllactose mixture as a novel food pursuant to Regulation (EU) 2015/2283
Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on 2'-fucosyllactose/difucosyllactose (2'-FL/DFL) mixture as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The NF is a powdered mixture mainly composed of two oligosaccharides, 2'-FL and DFL, which are produced together by fermentation with a genetically modified strain of Escherichia coli K12. The information provided on the manufacturing process, composition and specifications of the NF does not raise safety concerns. The applicant intends to add the NF in a variety of foods, including infant and follow-on formula, foods for infants and young children, foods for special medical purposes and food supplements. The target population is the general population except for food supplements, for which the target population is individuals above 1 year of age. Since the intake of 2'-FL and DFL from the NF at the proposed use levels is unlikely to exceed the intake level of naturally occurring 2'-FL and DFL in breastfed infants per kilogram body weight, the Panel concludes that the NF, a mixture of 2'-FL and DFL, is safe under the proposed conditions of use for the proposed target population. (C) 2019 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.Peer reviewe
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