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1.
2.
Perennial biomass crops (PBC) are considered a crucial feedstock for sustainable biomass supply to the bioeconomy that compete less with food production compared to traditional crops. However, large‐scale development of PBC as a means to reach greenhouse gas (GHG) mitigation targets would require not only the production on land previously not used for agriculture, but also the use of land that is currently used for agricultural production. This study aims to evaluate agricultural market impacts with biomass demand for food, feed, and PBC in four bioeconomy scenarios (“Business as usual,” “Improved relevance of bioeconomy,” “Extensive transformation to a bioeconomy,” “Extensive transformation to a bioeconomy with diet change”) to achieve a 75% GHG reduction target in the emission trading sector of the EU until 2050. We simulated bioeconomy scenarios in the energy system model TIMES‐PanEU and the agricultural sector model ESIM and conducted a sensitivity analysis considering crop yields, PBC yields, and land use options of PBC. Our results show that all bioeconomy scenarios except the one with diet change lead to increasing food prices (the average food price index increases by about 11% in the EU and 2.5%–3.0% in world markets). A combination of the transformation to a bioeconomy combined with diet change toward less animal protein in the EU is the only scenario that results in only moderately increasing food prices within the EU (+3.0%) and even falling global food prices (–6.4%). In addition, crop yield improvement and cultivation of PBC on marginal land help to reduce increases in food prices, but higher land prices are inevitable because those measures have only small effects on sparing agricultural land for PBC. For a transition to a bioeconomy that acknowledges climate mitigation targets, counter‐measures for those substantial direct and indirect impacts on agricultural markets should be taken into account.  相似文献   

3.
Associations between individual foods or nutrients and oxidative markers have been reported. Comprehensive measures of food intake may be uniquely informative, given the complexity of oxidative systems and the possibility of antioxidant synergies. We quantified associations over a 20-year history between three food-based dietary patterns (summary measures of whole diet) and a plasma biomarker of lipid peroxidation, F2-isoprostanes, in a cohort of Americans ages 18–30 at year 0 (1985–1986). We assessed diet at years 0, 7, and 20 through a detailed history of past-month food consumption and supplement use and measured plasma F2-isoprostanes at years 15 and 20. We created three dietary patterns: (1) a priori (“a priori diet quality score”) based on hypothesized healthfulness of foods, (2) an empirical pattern reflecting high fruit and vegetable intake (“fruit–veg”), and (3) an empirical pattern reflecting high meat intake (“meat”). We used linear regression to estimate associations between each dietary pattern and plasma F2-isoprostanes cross-sectionally (at year 20, n=2736) and prospectively (year 0/7 average diet and year 15/20 average F2-isoprostanes, n=2718), adjusting for age, sex, race, total energy intake, education, smoking, body mass index, waist circumference, physical activity, and supplement use. In multivariable-adjusted cross-sectional analysis, the a priori diet quality score and the fruit–veg diet pattern were negatively, and the meat pattern was positively, associated with F2-isoprostanes (all p values <0.001). These associations remained statistically significant in prospective analysis. Our findings suggest that long-term adherence to a diet rich in fruits and vegetables and low in red meat may decrease lipid peroxidation.  相似文献   

4.
The current system of food production is linked to both the increasing prevalence of chronic disease and the deterioration of the environment, and thereby calls for novel ways of producing nutritious foods in a sustainable manner. In the “longevity village” of Bama, China, we have identified two plant foods, hemp seed and bitter vegetable (Sonchus oleraceus), that are commonly consumed by its residents and grow abundantly in unfarmed land without fertilizers or pesticides. Here, we show that a diet composed of these two foods (the “HB diet”) provides a sufficient variety of nutrients and confers significant health benefits. Aged mice allowed ad libitum access to the HB diet not only had longer life spans and improved cognitive function but were also protected against age-related metabolic syndrome, fatty liver, gut dysbiosis and chronic inflammation compared to aged mice fed a control Western diet. Furthermore, longevity-related genes (including 5′adenosine monophosphate-activated protein kinase, sirtuin 1, nuclear respiratory factor 1 and forkhead box O3) were significantly up-regulated, while aging-related genes (including mammalian target of rapamycin and nuclear factor kappa B) were down-regulated. These results demonstrate that the HB diet is capable of promoting health and longevity, and present a sustainable source of healthy foods that can help control the prevalence of chronic diseases and reduce agricultural impact on the environment.  相似文献   

5.
  • 1.1. Specific Dynamic Action (SDA) effects of diet were investigated in the supralittoral isopod, Ligia pallasii, using defined chemical diets.
  • 2.2. “Apparent SDA”, or the total rise in metabolic rate following a meal, was resolved in animals eating a nutritionally complete chemical diet into three components: 8% mechanical costs of moving food through the gut, 40% “excitement costs” due to investigator disturbance and presence of food, and 52% SDA.
  • 3.3. Excitement costs in animals exposed to food but which chose not to eat showed non-significant variation between diets containing different levels of chemical nutrients, but were significantly less on a diet containing only cellulose and agar.
  • 4.4. SDA increased with increasing concentration of amino acids in the diet.
  • 5.5. Substitution of whole-protein casein for free amino acids in the diet had no significant SDA effect, while substitution of free amino acids in the ratio found in casein more than doubled the SDA effect.
  • 6.6. Deletion of alanine from the diet caused no significant effect on SDA, while deletion of phenylalanine caused a highly significant elevation in SDA.
  相似文献   

6.
《IRBM》2021,42(6):442-456
Background and ObjectivesAt the beginning of human civilization, human being needs to undergo immense physical labor to survive. During those days high-calorie diet was essential. However, the evolution of technology has changed the scenario and much lesser amount of physical labor is required to survive in modern hi-tech days, requiring less amount of calorie. The excess calorie gets deposited in the body in the form of white fat. As a consequence, obesity appears as an epidemic all over the world. Long term obesity causes many diseases like heart attack, stroke, diabetes, and many other ailments. It is tough for people, who honestly want to check their obesity by controlling food habits, to continue a static diet chart with fixed restricted foods for a long time. Most of the time, people give up such restrictions on food. It will be very useful if a system exists, that will generate a dynamic diet chart based on calorie spend by the body.MethodsThis research describes a system that will generate a dynamic diet chart based on calorie spend by the body and other data like user's BMI, food preferences, etc. In this system, user can tailor his/her diet chart by changing daily physical activities (activities that burn calories). The main contributions of the proposed system are as follows:
  • •A dedicated hardware system to quantify physical labor during walking and running throughout the day from feet pressure changes along with walk cycle detection.
  • •The proposed hardware system can distinguish between walk and run.
  • •A dynamic diet chart preparation system, where the user has the provision to plan his/her diet chart with food affinity.
The entire work is divided into two modules; the first one focuses on the hardware design to detect and quantify physical activities during “walking” and “running”. These data are used in the second part. The second part contains calorie calculation along with the preparation of a dynamic diet chart with food affinity. In the hardware design, an Application Specific Integrated Circuit (ASIC) is proposed to measure the physical activity during “walking” and “running”.ResultAt the time of hardware logic synthesis, VHDL and FPGA are used. Experimental results show that the proposed hardware provides more accurate results than a pedometer. There is no standard metric to measure the performance of the dynamic diet chart generation system. Competency of the dietitian at the time of setting the parameters, honesty of the users at the time of the interactive session, etc. are the main factors that influence heavily the performance of the dynamic diet chart preparation system. The advantage of dynamic diet chart is that users can modify the diet menu as per their wish, and the system generates a diet chart in such a way that calorie intake (through food items) is maintained properly. In addition to this, the user can plan his future meals.DiscussionThis work is an interdisciplinary work. It is a blending of electronics (FSM), design, and computation for decision making; the computation portion includes software engineering, soft computing, etc. Future plan of this work is to integrate this system with “Cloud” to provide different data analysis related services, like region-wise food habit pattern prediction, health-related statistics, etc.  相似文献   

7.
Recent analyses suggest that both gracile and robust australopithecines could have been “small object feeders” in the sense suggested by Jolly (1970). Data are presented on the diet of Theropithecus gelada, a grassland baboon which has been put forward as a possible analogy for this stage in hominid evolution. The relevance of these data for a reconstruction of australopithecine diet is assessed and the implications of a “small object” diet for the evolution of hunting are discussed.  相似文献   

8.
To date, studies of food overlap in Antarctic fish have been performed on a mixture of late juvenile and adult stages, leaving the young immature specimens (TL ≤ 10 cm) practically unexplored. We studied diet overlap and potential competition among early juvenile individuals in a coastal notothenioid community at Potter Cove, by analysing the stomach contents of 225 fish of 5 species collected in the summer of 2009–2010. We used frequency of occurrence (F %) and the coefficient “Q” for diet evaluation and the method of Tyler and the similarity index “S” for food overlap. Amphipods of the suborder Gammaridea were the main (Q > 2.900) and most frequent (% F) prey for all species, although Notothenia coriiceps also consumed gastropods of the family Littorinidae, mostly Laevilitorina antarctica. Secondary prey were algae for Notothenia rossii and N. coriiceps, calanoid (pelagic) and harpacticoid (benthic) copepods for Trematomus newnesi and the latter copepods and isopods of the family Munnidae for Lepidonotothen nudifrons. The reoccurrence of prey among fish species was 39.6 % and food overlap between 90 % of species pairs was under 58 %. Because similarly low values of diet overlap were reported for intermediate/advanced juveniles and adults of the same species at the same site, we conclude that there is no difference in the degree of interspecific food overlap and therefore potential competition between the immature and mature fraction of the fish community. Food competition is avoided by resource partitioning along a depth gradient or by different prey species.  相似文献   

9.
The assimilation of food inPorcellio scaber, considered over the entire life cycle, follows a two-phase function with a turning point at a body weight of about 3 mg. It is assumed that an important factor in this relationship is the efficiency of digestion, which should depend on the surface/volume ratio of the mid-gut and on the speed with which food is passed through the intestine. Calculation of these values reveals a size-dependent drop in efficiency of digestion roughly following the “surface rule”. The drop in efficiency of digestion may pose to the system a problem of information retrieval since inefficient digestion increases the “noise” level against which specific “signals” have to be selected — that is, specific molecules have to be absorbed and used in syntheses of cell constitutents. In order to offset decreasing efficiency of digestion, the system would have to increase redundancy, e. g. by assimilating progressively more food and thus, inevitably, increasing “cost” of some kind. The young larvae ofP. scaber, up to a body weight of 3 mg, do, in fact increase the amount of food assimilated in proportion to the calculated increase in redundancy. At about this critical size a switch in metabolism seems to take place, and weight specific assimilation of food decreases despite the continuously dropping efficiency of digestion. The actual use that the organism makes of the food ingested is represented by the ratio assimilation/cost of redundancy. Calculation of this ratio over the whole life cycle shows it to parallel neatly the curve for the monthly growth rate of the species.  相似文献   

10.
Cassava (Manihot esculenta) is a cyanide-containing food crop used by many indigenous peoples in Amazonia. Tukanoan Indians in Northwest Amazonia utilize both “bitter” and “sweet” cassava cultivars. Those classified as “bitter” are the dietary staple. Analysis of 13 commonly used “bitter” cultivars indicates that they are high in cyanide in comparison to values reportedin the literature. The Tukanoan practice of including the inner peel in the edible portion contributes to the high cyanide values found.  相似文献   

11.
Host resistance and parasite virulence are influenced by multiple interacting factors in complex natural communities. Yet, these interactive effects are seldom studied concurrently, resulting in poor understanding of host‐pathogen‐environment dynamics. Here, we investigated how the level of opportunist pathogen virulence, strength of host immunity and the host condition manipulated via diet affect the survival of wood tiger moth Parasemia plantaginis (Arctidae). Larvae from “low cuticular melanin” and “high cuticular melanin” (considered as low and high pathogen resistance, respectively) selection lines were infected with moderately and highly virulent bacteria strains of Serratia marcescens, while simultaneously manipulating host diet (with or without antibacterial compounds). We measured host survival and food preference before and after infection to test whether the larvae “self‐medicate” by choosing an anti‐infection diet (Plantago major, i.e., plantain leaf) over lettuce (Lactuca sativa). “High melanin” larvae were more resistant than “low melanin” larvae to the less virulent strain that had slower growth and colonization rate compared with the more virulent strain. Cuticular melanin did not enhance survival when the larvae were infected with the highly virulent strain. Anti‐infection diet enhanced survival of the “high melanin” but not the “low melanin” hosts. Survival was dependent on family origin even within the melanin selection lines. Despite the intrinsic preference for lettuce, no evidence of self‐medication was found. These results demonstrate that the relative benefit of host cuticular melanin depends on both diet and pathogen virulence: plantain diet only boosted the immunity of already resistant “high melanin” hosts, and cuticular melanin increased host survival only when infected with moderately virulent pathogen. Moreover, there was considerable variation in host survival between families within both melanin lines suggesting genetic basis for resistance. These results indicate that although melanin is an important predictor of insect immunity, its effect on disease outcomes greatly depends on other interacting factors.  相似文献   

12.
The largely unsolved problems in the theoretical analysis of differentiation and ageing involve a substantial component of linguistic (semantic) difficulties. Some of these are simple traps of ambiguity, resulting from metaphorical or analogical employment of established terms—for example, “terminal differentiation” (loss of division potential in vitro) as a borrowing from “differentiation” as used by developmental biologists, or “commitment” by analogy with “determination”. Some difficulties represent a failure to adopt (at least provisionally) an operational (empirical) view—for example, failure to ask what is the nature of the evidence for the view that a fertilized ovum is totipotential, or to scrutinize the evidence for the view that cells “terminally differentiated” in vitro in a conventional medium are in fact moribund under all conditions, or to examine more closely the view that the differentiated state and the cycling state are mutually exclusive.With respect to the problem of ageing, we review some of the critical experiments on ”terminal differentiation” or “clonal senescence”. We then proceed to consider some of the models that have been proposed, including a molecular model proposed by the author which appears to overcome some of the objections to other models. Some of the models exemplify the results of what are ultimately semantic vices.The problems with which these remarks began should indeed yield to the immense and novel resources of molecular biology. But the development of complete analyses demands not only good luck and delicate technique but also critical semantic clarity and severity. Given the best tools, we shall solve major theoretical problems only if we understand quite fully what problem it is that we are trying to solve—and the history of science illustrates that this is not as elementary a matter as it sounds. For the working scientist semantics (and indeed all philosophy of science) is not an indulgence or a frill, but a basic technical resource.  相似文献   

13.
For the past few years, people everywhere have been “going Paleo.” Websites and social media touting the benefits of eating a “Paleo diet” and following a “Paleolithic life style” serve as calls to arms for health‐conscious individuals seeking information about the latest health and fitness trends. Many of these people participate in programs such as Crossfit, which involve major social and life‐style modification components and therefore facilitate the dissemination of dietary fads.1 The PALEOf(x)TM conference, which bills itself as “the world's premier holistic wellness event,” has attracted sellout crowds of thousands of attendees for the last four years.2 Consumers can wear Paleo clothing, download Paleo shopping and exercise apps to their smartphones, order prepackaged Paleo food, prepare it using Paleo cooking implements, or expediently buy Paleo convenience foods from Paleodiet? vending machines3 and “Cultured Caveman” food trucks.4 The Paleo diet is touted by movie stars, reality TV personalities, and professional athletes, including LeBron James and the entire Miami Dolphins NFL team.5,6 Books with titles such as The Primal Blueprint,7 Cavewomen Don't Get Fat,8 and Paleo Perfected9 (the latter by the stodgy America's Test Kitchen) are legion, and many are bestsellers.  相似文献   

14.
The possibility of prolonged coevolution of bacterial reception protein and viral adsorption one is questioned in this paper. A general deterministic model of ecosystem “phage-bacteria” is formulated. Analysis of the model accentuates the problem of clearing up conditions that provide steady regimes not of coexistence but coevolution, i.e. successive mutational changes of mutually “coadaptive” pairs of mutant strains of bacteria and phages. Heuristic validity of this model in a framework of some actual problems and paradoxes of molecular evolution theory is particularly emphasized.  相似文献   

15.
On optimal nonlinear associative recall   总被引:6,自引:0,他引:6  
The problem of determining the nonlinear function (“blackbox”) which optimally associates (on given criteria) two sets of data is considered. The data are given as discrete, finite column vectors, forming two matricesX (“input”) andY (“output”) with the same numbers of columns and an arbitrary numbers of rows. An iteration method based on the concept of the generalized inverse of a matrix provides the polynomial mapping of degreek onX by whichY is retrieved in an optimal way in the least squares sense. The results can be applied to a wide class of problems since such polynomial mappings may approximate any continuous real function from the “input” space to the “output” space to any required degree of accuracy. Conditions under which the optimal estimate is linear are given. Linear transformations on the input key-vectors and analogies with the “whitening” approach are also discussed. Conditions of “stationarity” on the processes of whichX andY are assumed to represent a set of sample sequences can be easily introduced. The optimal linear estimate is given by a discrete counterpart of the Wiener-Hopf equation and, if the key-signals are noise-like, the holographic-like scheme of associative memory is obtained, as the optimal nonlinear estimator. The theory can be applied to the system identification problem. It is finally suggested that the results outlined here may be relevant to the construction of models of associative, distributed memory.  相似文献   

16.
Ecological trait data are essential for understanding the broad‐scale distribution of biodiversity and its response to global change. For animals, diet represents a fundamental aspect of species’ evolutionary adaptations, ecological and functional roles, and trophic interactions. However, the importance of diet for macroevolutionary and macroecological dynamics remains little explored, partly because of the lack of comprehensive trait datasets. We compiled and evaluated a comprehensive global dataset of diet preferences of mammals (“MammalDIET”). Diet information was digitized from two global and cladewide data sources and errors of data entry by multiple data recorders were assessed. We then developed a hierarchical extrapolation procedure to fill‐in diet information for species with missing information. Missing data were extrapolated with information from other taxonomic levels (genus, other species within the same genus, or family) and this extrapolation was subsequently validated both internally (with a jack‐knife approach applied to the compiled species‐level diet data) and externally (using independent species‐level diet information from a comprehensive continentwide data source). Finally, we grouped mammal species into trophic levels and dietary guilds, and their species richness as well as their proportion of total richness were mapped at a global scale for those diet categories with good validation results. The success rate of correctly digitizing data was 94%, indicating that the consistency in data entry among multiple recorders was high. Data sources provided species‐level diet information for a total of 2033 species (38% of all 5364 terrestrial mammal species, based on the IUCN taxonomy). For the remaining 3331 species, diet information was mostly extrapolated from genus‐level diet information (48% of all terrestrial mammal species), and only rarely from other species within the same genus (6%) or from family level (8%). Internal and external validation showed that: (1) extrapolations were most reliable for primary food items; (2) several diet categories (“Animal”, “Mammal”, “Invertebrate”, “Plant”, “Seed”, “Fruit”, and “Leaf”) had high proportions of correctly predicted diet ranks; and (3) the potential of correctly extrapolating specific diet categories varied both within and among clades. Global maps of species richness and proportion showed congruence among trophic levels, but also substantial discrepancies between dietary guilds. MammalDIET provides a comprehensive, unique and freely available dataset on diet preferences for all terrestrial mammals worldwide. It enables broad‐scale analyses for specific trophic levels and dietary guilds, and a first assessment of trait conservatism in mammalian diet preferences at a global scale. The digitalization, extrapolation and validation procedures could be transferable to other trait data and taxa.  相似文献   

17.
18.
Can diet have a significant impact on the ability of organisms to sense and locate food? Focusing on the bacterial feeder Caenorhabditis elegans, we investigated what effect preconditioning on a range of bacterial substrates had on the subsequent chemotaxis process involved in the nematode locating other bacterial populations. Remarkably, we found that C. elegans, initially fed on a diet of Escherichia coli OP50, was significantly impaired in finding E. coli OP50 populations, compared to other available bacterial populations (P < 0.001). We found similar results for another bacterial feeding nematode species, suggesting that a general “substrate legacy” may operate across a wide range of organisms. We discuss this important finding with respect to the variation in response exhibited within a given nematode population, and the impact nematode migration has on bacterial dispersal in the environment.  相似文献   

19.
According to the classical model, the “shoot” consists only of the categories “caulome” (“stem” sensu lato) and “phyllome” (“leaf” sensu lato), (and “root” in cases of “adventitious” root formation). If lateral shoots are present, their position is axillary. Consequently, caulome as well as phyllome are inserted on the caulome and only on the caulome. This classical model of the shoot has two disadvantages of great consequence: (1) Intermediate organs cannot be accepted as such, but have to be interpreted (i.e. categorized) as either caulome or phyllome (or root) by distortion of the actual similarity. (2) Certain positional changes of organs cannot be accepted as such, but have to be “explained” by congenital fusion. The new conception of the shoot will have the advantages of the classical model but not its disadvantages. Hence, the shoot may consist of the following parts: (main and lateral) shoot, caulome, phyllome, root, emergence, and structures intermediate between (i.e. partially homologous to) any of the preceding. Thus, the five categories of the classical model, namely “shoot”, “caulome”, “phyllome”, “root” and “emergence” are no longer mutually exclusive; they may merge into each other due to an actual or potential continuum. Intermediate organs are therefore accepted as such; for example, an organ may be characterized as an intermediate form between a caulome and a phyllome. Besides intermediate forms, all changes in position are accepted as such. Hence, the following positional relations are possible: caulome and phyllome may be inserted on the caulome, caulome and phyllome may be inserted on the phyllome; roots may be inserted on caulome or phyllome; intermediate forms may be inserted on the caulome, phyllome, or other intermediate forms. Consequences of the new conception for morphological research are pointed out, especially for homologization, evolutionary considerations, and the direction in which research progresses.  相似文献   

20.
Nowadays, the strong relationship between diet and health is well known. Although the primary role of diet is to provide nutrients to fulfill metabolic requirements, the use of foods to improve health and the state of well-being is an idea increasingly accepted by society in the last three decades. During the last years, an important number of scientific advances have been achieved in this field and, although in some situations, it is difficult to establish a distinction between “harmful” and “good” bacteria, experts agree in classifying the genera Bifidobacterium and Lactobacillus as beneficial bacteria. Thus, several strategies can be used to stimulate the proliferation of these beneficial intestinal bacteria, being one of them the consumption of prebiotics. The development of new prebiotics, with added functionality, is one of the most serious challenges shared not only by the scientific community but also by the food industry. The objective of this work was to evaluate the potential prebiotic effect of red and white grape residues, both obtained during the winemaking process. For such purpose, an in vitro study with pure cultures of Lactobacillus and Bifidobacterium was first conducted. Secondly, a study with mixed cultures using human fecal inocula was carried out in a simulator of the distal part of the colon. The obtained results showed an increase in the Lactobacillus and Bifidobacterium population, indicating that these ingredients are serious candidates to be considered as prebiotics.  相似文献   

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