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European large-scale farmland investments and the land-water-energy-food nexus Texte intégral
2017
Siciliano, Giuseppina | Rulli, Maria Cristina | D’Odorico, Paolo
The escalating human demand for food, water, energy, fibres and minerals have resulted in increasing commercial pressures on land and water resources, which are partly reflected by the recent increase in transnational land investments. Studies have shown that many of the land-water issues associated with land acquisitions are directly related to the areas of energy and food production. This paper explores the land-water-energy-food nexus in relation to large-scale farmland investments pursued by investors from European countries. The analysis is based on a “resource assessment approach” which evaluates the linkages between land acquisitions for agricultural (including both energy and food production) and forestry purposes, and the availability of land and water in the target countries. To that end, the water appropriated by agricultural and forestry productions is quantitatively assessed and its impact on water resource availability is analysed. The analysis is meant to provide useful information to investors from EU countries and policy makers on aspects of resource acquisition, scarcity, and access to promote responsible land investments in the target countries.
Afficher plus [+] Moins [-]Design of gel structures in water and oil phases for improved delivery of bioactive food ingredients Texte intégral
2020
Mao, Like | Lu, Yao | Cui, Mengnan | Miao, Song | Gao, Yanxiang
Gels are viscoelastic systems built up with a liquid phase entrapped in a three-dimensional network, which can behave as carriers for bioactive food ingredients. Many attempts have been made to design gel structures in the water phase (hydrogels, emulsion gels, bigels) or oil phase (organogels, bigels) in order to improve their delivery performances. Hydrogels are originated from proteins or polysaccharides, which are suitable for the delivery of hydrophilic ingredients. Organogels are mainly built up with the self-assembling of gelator molecules in the oil phase, and they offer good carriers for lipophilic ingredients. Emulsion gels and bigels, containing both aqueous and oil domains, can provide accommodations for lipophilic and hydrophilic ingredients simultaneously. Gel structures (e.g. rheology, texture, water holding capacity, swelling ratio) can be modulated by choosing different gelators, modifying gelation techniques, and the involvement of other ingredients (e.g. oils, emulsifiers, minerals, acids), which then alter the diffusion and release of the bioactive ingredients incorporated. Various studies have proved that gel-based delivery systems are able to improve the stability and bioavailability of many bioactive food ingredients. This review provides a state-to-art overview of different gel-based delivery systems, highlighting the significance of structure–functionality relationship, to provide advanced knowledge for the design of novel functional foods.
Afficher plus [+] Moins [-]Elevated CO2 (FACE) Affects Food and Feed Quality of Cereals (Wheat, Barley, Maize): Interactions with N and Water Supply Texte intégral
2015
Erbs, Martin | Manderscheid, Remy | Jansen, Giesela | Seddig, Sylvia | Wroblewitz, Stefanie | Hüther, Liane | Schenderlein, Anke | Wieser, Herbert | Dänicke, Sven | Weigel, Hans-Joachim
Climate change will not only affect crop biomass production but also crop quality. While increasing atmospheric CO2 concentrations are known to enhance photosynthesis and biomass production, effects on the chemical composition of plants are less well known. This is particularly true for major crop plants with respect to harvestable yield quality. Moreover, it remains open, how these effects on quality may be realized under field conditions and how management (e.g. plant N nutrition) or environmental factors (e.g. water availability) will alter impacts of elevated CO2. Here we report on a series of free air CO2 enrichment (FACE) experiments with wheat and barley and with maize in which effects of elevated CO2 combined with different levels of N supply (wheat and barley) and with drought stress (maize) on grain and biomass quality characteristics were investigated. Winter wheat and winter barley (1st experiment) and maize (2nd experiment) were grown in the field each for two growing seasons under ambient and elevated CO2 concentration (FACE, 550μmol mol-1). Wheat and barley were grown under adequate N supply and under 50% of adequate N as sub-treatments. In the maize experiment rain shelters were used to create two different levels of plant water supply (well-watered and drought stress – about 50% of well-watered) as sub-treatments. Treatment effects on elemental composition and a variety of quality characteristics of the plant material at final harvest were investigated. This included a detailed analysis of wheat grain protein components and of different fiber fractions of maize. Compiled results of the relative effects of elevated CO2, N and drought stress treatments on different quality parameters of the crops are presented.
Afficher plus [+] Moins [-]Efecto de la adición de minerales en el agua o alimento sobre La frecuencia cardiaca, en pollos de engorde sometidos a estrés calórico crónico y agudo Texte intégral
2008
Rojas U, Jesús A(Universidad Central de Venezuela Facultad de Agronomía) | Comerma S, Simón G(Universidad Central de Venezuela Facultad de Agronomía) | Chacón, Tony(Universidad Central de Venezuela Facultad de Agronomía) | Rossini, Mario(Universidad Central de Venezuela Facultad de Agronomía) | Zerpa, Héctor(Universidad Central de Venezuela Facultad de Agronomía) | Farfán, Charly(Universidad Central de Venezuela Facultad de Agronomía) | Vasco De Basilio,(Universidad Central de Venezuela Facultad de Agronomía)
The effects of mineral addition in feed or water on performance parameters and heart rate (HR) were evaluated in broilers at 28-35 d and 36 d under both chronic heat stress (CHS) and acute heat stress (AHS) in laboratory conditions. One-hundred ninety two broilers were used, distributed in 6 cages and 4 rooms, according to weight, with 8 animals per cage: four males and four females. For individual measurements, at 21 d, 2 males and 2 females out of 8 broilers were chosen and classified as: heavy male; light male; heavy female and; heavy female. For HR measurement, 48 broilers were used. The assay included 3 treatments (T): T1: A basal diet (BD); T2: BD plus mineral addition in feed; T3: a BD plus mineral addition in water. The experimental design was completely randomized with 4 repetitions/treatment. Composition of the mineral formula used was: NaHCO3 (0.83%); NH4Cl (0.07%); NaCl (0.30%), attaining a final balance of 240 mEq/kg. The following was measured: feed consumption (FC), water consumption (WC) body weight gain (BWG), feed conversion efficiency (FCE), body temperature (BT), HR, hyperventilation level (HL), blood pH, blood gases (BG), and blood electrolytes. The results were analyzed with ANOVA and mortality rate (MR) was evaluated through the Chi-square procedure. The results show that FC, BWG and FCE were similar for all T. The WC for T2 (300±23.0 mL/bird/period) and T3 (290±19.0 mL/bird/period) was higher (P=0,016) than for T1 (220±12 mL/bird/period). The lowest M (15.63 % vs 37.50%) was found in T3 vs T1 (P<0.001). The HR and HL were not affected by T during CHS and AHS. Tachycardia was the result of AHS due to higher environmental temperatures. Assessment of parameters such as cardiac output, blood pressure, stroke volume, total peripheral resistance, electrocardiogram wave morphology is advised to clarify cardiovascular function under heat stress. | Se evaluaron en ambiente semicontrolado, los efectos de adición de minerales en agua o alimento sobre parámetros productivos y frecuencia cardiaca (FC) en pollos de engorde de 28-35 d y 36 d bajo estrés calórico crónico (ECC) y estrés calórico agudo (ECA), respectivamente. Se usó un total de 192 pollos, según peso, distribuidos en 6 corrales y 4 salas, asignándose 8 pollos/corral: cuatro machos y cuatro hembras. A los 21 d, para las medidas individuales, de los 8 pollos se seleccionaron 2 machos y 2 hembras, identificándolos como macho pesado, macho liviano, hembra pesada y hembra liviana. Para FC, se escogieron 48 pollos. El ensayo incluyó 3 tratamientos (T): T1: Alimento balanceado (AB); T2: AB con adición mineral y T3: AB con adición mineral en agua. El diseño utilizado fue completamente al azar con 4 repeticiones/tratamiento. La composición del suplemento mineral fue: NaHCO3 (0,83%); NH4Cl (0,07%) y; NaCl (0,30%) con un balance electrolítico de 240 mEq/kg. Se evaluó consumo de alimento (CAL), consumo de agua (CAG), ganancia de peso (GP), conversión alimenticia (CA), temperatura corporal (TC), nivel dehiperventilación (NH), FC, gases y electrólitos en sangre, y mortalidad (M). Los datos fueron analizados mediante ANAVAR. Se usó Chi cuadrado para calcular el porcentaje de mortalidad. Los resultados muestran que CAL, GP y CA fueron similares en todos los T. El CAG en T2 (300 ± 23,0 mL/pollo/período) y T3 (290±19,0 mL/pollo/período) fue mayor (P=0,016) que T1 (220±12 mL/pollo/período). La menor M (15,63 % vs 37,50 %) se produjo entre T3 vs T1 (P<0,001). Los T no afectaron NH ni FC durante ECC y ECA. En todos los T hubo taquicardia significativa (P<0,001) solamente en ECA, debido a mayores temperaturas ambientales. Se recomienda determinar gasto cardiaco, presión arterial, volumen de eyección, resistencia periférica total y morfología de ondas del electrocardiograma, para clarificar la función cardiovascular en condiciones de estrés calórico.
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