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71.
María J. Estrela Jos A. Valiente David Corell David Fuentes Alejandro Valdecantos 《Agricultural and Forest Meteorology》2009,149(11):1896
A mountainous plot located in the interior of the Valencia region (east coast of the Iberian Peninsula) was identified for reforestation using the fog-water collection potential prevailing in the area. Fog data were obtained by means of an instrument ensemble consisting of a passive cylindrical fog-water collector, a rain gauge, a wind direction and velocity sensor and a temperature and humidity probe. Preliminary results gave rise to the additional deployment of a low-cost 18-m2 flat-panel collector connected to three 1000-l tanks for larger scale fog-water collection and storage. The 2007 annual rate of fog water that could be derived from the instrument ensemble amounted to 3.3 l/m2/day, which turn out to fill up the storage tanks completely in only 5 months, even though the flat-panel collector could not be operative 100% of the time. The study made use of the in situ stored water and a micro-irrigation network to irrigate a plot of reforestation seedlings through small water pulses localized deep in the planting hole during the summer dry period. Until the present, this forest location had always shown a difficult self-recovery due to the high level of land degradation resulting from recurrent forest fires in the past. Results indicate that survival rates and seedling performance of the two species planted, Pinus pinaster and Quercus ilex, improved with the use of small timely waterings and additional treatments with composted biosolid. 相似文献
72.
Brittany Huschka Carolyn Challacombe Alejandro G. Marangoni Koushik Seetharaman 《Cereal Chemistry》2011,88(3):253-259
Monoacylglycerol‐stabilized oil in water emulsion (MAG gel) is an alternate shortening that is free of trans fatty acids, and low in saturated fatty acids. However, the behavior of MAG gels in comparison to other lipids has not been studied. This study investigated effects of structured MAG gel, a mixture of MAG gel unstructured components (Mixture), canola oil (Oil), or interesterified soy shortening (IE Soy) at different levels (6–24%) on hard or soft wheat dough properties. Doughs were prepared with different lipid types at equivalent lipid contents. Dough mixing and water absorption parameters were evaluated using a farinograph; gluten behavior was measured using a gluten peak tester (GPT); and pasting characteristics were measured using a micro‐viscoamylograph (MVAG). Water absorption values decreased with increasing lipid content. Dough development times were similar between the MAG gel and IE Soy, but farinogram curve characteristics during mixing were similar between MAG gel, Mixture, and Oil. The trend for peak max time in GPT was similar between MAG gel and IE Soy exhibiting delayed gluten aggregation; whereas Mixture and Oil exhibited earlier gluten aggregation. In MVAG, starch interaction with monoglyceride component of MAG gel and Mixture appeared to be the dominating factor resulting in increased pasting temperature and a second viscosity peak during cooling at higher levels of lipid addition. 相似文献
73.
Miguel González-Lozano Daniel Mota-Rojas E. Yadira Velázquez-Armenta Alejandro A. Nava-Ocampo Rafael Hernández-González Marcelino Becerril-Herrera María E. Trujillo-Ortega María Alonso-Spilsbury 《The Canadian veterinary journal. La revue veterinaire canadienne》2009,50(12):1273-1277
Sixty hybrid Yorkshire-Landrace penned sows, 30 with eutocic farrowing and 30 experiencing a dystocic parturition, were studied to evaluate the obstetric and neonatal outcomes to low doses of oxytocin administered at advanced stages of parturition. Animals in each group were randomly subdivided into 2 subgroups: 15 eutocic and 15 dystocic sows received oxytocin 0.083 IU/kg (equivalent to 1 IU/12 kg body weight), administered intramuscularly after the delivery of the 5th piglet; the other 15 eutocic and 15 dystocic sows received saline solution intramuscularly at the same time. Oxytocin decreased the number of intrapartum deaths by approximately 50% (P = 0.002). No piglet was born dead from the saline- and oxytocin-treated eutocic sows. The highest viability score was observed among piglets born to eutocic sows treated with oxytocin. In summary, this dose schedule would help to decrease the number of stillbirths in both eutocic and dystocic farrowing sows. 相似文献
74.
Marca MC Gómez-Quintero A Viñuales C Rodríguez-Yoldi MJ 《Veterinary journal (London, England : 1997)》2009,180(2):213-220
Lipopolysaccharide (LPS) is an endotoxin comprising part of the cell wall of Gram-negative bacteria. It is able to induce a septic state and the release of several pro-inflammatory cytokines that are known to be responsible for hormonal changes in humans and animals. The aim of this study was to evaluate changes in plasma adrenocorticotrophic hormone (ACTH), corticosterone and cortisol levels in a rabbit model in which sepsis was induced by the intravenous administration of LPS. The possible involvement of several protein kinases, namely protein kinase A (PKA), C (PKC) and mitogen-activated protein kinases (MAPKs), and proteasome was also assessed. The results indicated that LPS induced significant increases in plasma ACTH, corticosterone and cortisol concentrations in rabbits. Moreover, protein kinases and proteasome seemed to mediate the hormone response to LPS as treatment with specific inhibitors prior to LPS administration was able to reduce, delay, or, in some cases, inhibit the hormone increases. The findings may help to construct strategies to protect and treat animals with endotoxaemia. 相似文献
75.
A butanol extract of dried leaves of Bahuinia candicans showed, in vitro, a stimulatory effect of glucose uptake in isolated gastric glands of normal and alloxan-diabetic rabbits. The extract (0.001-0.07 mg/mg protein) produced a dose-dependent effect and was similar to the effect of insulin (1-100 nM). These findings suggest that the extract contains compound(s) that efficiently increase glucose transport at the basolateral side of isolated gastric glands. 相似文献
76.
Herrero M Jaime L Martín-Alvarez PJ Cifuentes A Ibáñez E 《Journal of agricultural and food chemistry》2006,54(15):5597-5603
In this work, extraction of antioxidant compounds from Dunaliella salina microalga is optimized by combining pressurized liquid extraction (PLE) and experimental design (three-level factorial design) with three different solvents (hexane, ethanol, and water). Two main factors were considered, the extraction temperature (40, 100, and 160 degrees C) and the extraction time (5, 17.5, and 30 min). As response variables, the extraction yield (percent dry weight/initial weight) and the antioxidant activity of the extracts (determined using the TEAC method) were used. The parameters of the model were estimated by multiple linear regression. Results showed that the extraction temperature was the factor having the strongest influence (positive) on the two response variables. The best yields were obtained with ethanol at the higher extraction temperature and time tested. Besides, although hexane extracts provided the best antioxidant activity, ethanol extracts were also very active. The chemical characterization of ethanol extracts was carried out using HPLC-DAD, and attempts have been made to correlate their chemical composition with the antioxidant activity measured. Results pointed out that the extracts contained, besides all-trans-beta-carotene and isomers, several different minor carotenoids that seemed to make a contribution to the antioxidant activity of the extracts. 相似文献
77.
Guillermina Dalla-Salda Alejandro Martinez-Meier Hervé Cochard Philippe Rozenberg 《Forest Ecology and Management》2009
Drought response of three Douglas-fir clones (slow, intermediate and fast growing) inhabiting two different climatic regimes in France was examined. We used the hydraulic conductivity and the percent loss of conductivity due to embolism from stems and branches as well as wood microdensity measurements to determine the role of genetics in the control of embolism in this species. Conductivity and tree-ring’s microdensity variables (ring width: RW, mean ring density: MRD, minimum ring density: MID and maximum ring density: MAD) were compared in growth rings in all three clones during a typical year (2002) vs. an extremely dry year (2003). A new method was developed in order to assess axial hydraulic specific conductivity (Ks) within tree rings. The results show that branches are more resistant to embolism than stems, and that there are significant differences in embolism resistance among the clones between the two sites. Ks varied between years, sites and clones but the site exerted the most significant effect. Lartimache (more humid site during 2003) trees showed substantially higher Ks than those inhabiting Chassenoix (strongly affected by the 2003 heat and drought wave site). Wood analysis showed a significant year effect for all ring variables and a significant clone effect for all ring variables except for MAD, while the site effect was significant for MRD and MAD. The existence of a genetic control for the study traits indicates that Douglas-fir populations introduced in France may have a selection potential to face extreme climate events like the 2003 heat and drought wave. 相似文献
78.
Manuel Alejandro Merlo Ismael Cross Ana Rodríguez‐Rúa Manuel Manchado Laureana Rebordinos 《Aquaculture Research》2013,44(6):974-984
The meagre (Argyrosomus regius) is a commercially important species for fisheries, and aquaculture production has been increasing in recent years. However, this growing importance has not been matched by increased genetic knowledge of the species. For this reason, an initial approach has been made to understanding the genetics of the meagre, using three particular multigene families (45S and 5S ribosomal DNA and U2 snRNA gene) as both molecular and cytogenetic markers. Only one type of 5S rDNA and only one ITS‐1 (from 45S rDNA) were obtained, and these therefore could provide the basis for the development of genetic markers for this species. However, the U2 snRNA gene produced a multi‐band electrophoretic pattern, and some of these bands were demonstrated to be linked with the U1 snRNA gene. This linkage could also provide a good species‐specific marker which could be useful for tracing the evolutionary history of the Sciaenidae family. In this study, we have described for the first time the karyotype of the meagre: this is composed of 48 acrocentric chromosomes. Each of the three gene families were localized on different chromosome pairs, although the U2 snRNA gene probe was also located scattered throughout the genome of the meagre, as expected by the amplification pattern. 相似文献
79.
Marisol Berti Rosemarie WilckensSusana Fischer Alejandro SolisBurton Johnson 《Industrial Crops and Products》2011,34(2):1358-1365
Camelina (Camelina sativa L.) was introduced for the first time in Chile in 2008 as a potential feedstock for biodiesel and also as high omega-3-containing seed oil for the salmon feed industry. The objective of this study was to determine the optimum seeding date to maximize camelina seed yield in South Central Chile. The experiment was conducted under dryland conditions in Chillán, El Carmen, Los Angeles, Gorbea, and Osorno in 2008 and in Chillán and Los Angeles in 2009. The experimental design was a RCB with a split-plot arrangement with four replicates, where the main plot was the seeding date (five dates) and the sub-plot the spring type cultivars (Gold of Pleasure, Suneson, and Blaine Creek). Seeding dates at each environment were targeted to 30 April, 15 May, 30 May, 30 June, and 30 July of 2008 and 2009. The combined analysis of variance indicated no cultivar main effect or interactions with cultivar. The date by environment interaction was significant for seed yield. There were no seed yield differences among seeding dates in Chillán and El Carmen. The first three seeding dates were the highest yielding in Los Angeles and Osorno, and only the first seeding date was significantly higher in seed yield in Gorbea. Highest seed yield at Los Angeles, Gorbea, and Osorno were 1995, 1310, and 2314 kg ha−1. Seed oil content was not different among seeding dates in Chillán and El Carmen. Highest seed oil content occurred at Osorno and Gorbea on the first three seeding dates and ranged from 420 to 457 g kg−1. Spring camelina cultivars are well adapted to South Central Chile as a winter annual crop when seeded before 15 May except in Osorno when seeded before 30 May. No disease or insectpests were observed except for Aster Yellow infestation at Chillán and Los Angeles. Camelina has great potential as an oilseed for biodiesel and as a source of omega-3 for the pharmaceutical industry but markets for it need to be developed locally for camelina to become an option for growers. 相似文献
80.
Tissue composition,blood biochemistry and histology of digestive organs in Senegalese sole (Solea senegalensis) juveniles fed diets containing different plant protein ingredients 下载免费PDF全文
A. Rodiles M. Herrera I. Hachero‐Cruzado I. Ruiz‐Jarabo J.M. Mancera M.L. Cordero S.P. Lall F.J. Alarcón 《Aquaculture Nutrition》2015,21(6):767-779
The aim of this study was to determine the impact of diets with different plant protein ingredients on proximate composition, tissue metabolites and tissue fatty acid composition, as well as hepatic and intestinal histological modifications in Senegalese sole (Solea senegalensis). Fish (21.5 ± 2.8 g body weight) were fed six isonitrogenous and isoenergetic diets during 11 weeks. A control diet containing fish meal as the main protein source was compared with five experimental diets replacing 30% fish meal protein by different plant protein sources: soybean meal (SBM), soybean protein concentrate (SPC), soybean protein isolate (SPI), wheat gluten meal (WGM) or pea protein concentrate (PPC). The inclusion of different plant protein did not significantly affect growth and proximate composition of fish. The hepatosomatic index was not significantly different to the control group; however, utilization of WGM significantly increased hepatocyte size. Plasma protein values and muscle triglycerides were influenced by the inclusion of SBM and WGM in the diets respectively. Feeding fish on SBM, WGM and PPC diets significantly enhanced n‐6 fatty acid levels in muscle, particularly linoleic acid. None of the plant protein ingredient used in the diets decreased arachidonic, eicosapentaenoic as well as docosahexaenoic acid values in liver and muscle. Overall, histological studies did not reveal the existence of any intestinal alterations induced by the inclusion of different plant proteins. Despite moderate changes produced by SBM, SPC and WGM, inclusion of dietary plant protein ingredients has no major impact on growth, tissue and blood biochemistry, fatty acid profile and gut integrity of Senegalese sole juveniles. 相似文献