Lighting systems evaluation for indoor living walls     

Gregorio Egea  Luis Pérez-Urrestarazu  Julio González-Pérez  Antonio Franco-Salas  Rafael Fernández-Cañero 《Urban Forestry & Urban Greening》2014,13(3):475-483

Living walls (LW) are vertical greening systems that are becoming popular due to their multiple social and environmental benefits. When LW are installed indoors, a lightening system is often required to ensure an appropriate plant development. This work assesses the performance of three artificial lighting systems on six indoor LW [0.7 m (wide) × 0.7 m (high)] placed at two distances from the light source. The plant species selected for the tests were Soleirolia soleirolii and Spathiphyllum wallisii, which are frequently used in indoor LW. Three different lamps were used in the experiment: incandescent (IL), fluorescent (FL) and metal halide (MHL) lamps, all of them with an input electric power of ≈250 W. Differences in plant growth were only observed when the LW were close to the light source (about 1 m) but not at greater distances (≈1.5 m). IL had the poorest performance. Despite the lower photosynthetic photon flux density efficiency of FL compared with MHL, FL light enabled plants placed in the upper LW (closer to light source) reached similar size to those grown under MHL. Plant quality attributes were generally not affected by light type or the distance to light source. IL and FL generated higher total water losses (i.e. transpiration plus evaporation) than MHL on a LW basis. When expressed per unit of LW area covered by vegetation, FL and MHL reduced water consumption by 34% and 56%, respectively, as compared to IL. Overall, our results indicate that both FL and MHL outperform IL and have a similar ornamental performance, whereas MHL are more advantageous than FL in terms of water consumption and annual cost.  相似文献   

Identification of Ensifer strains isolated from root nodules of Medicago hispida grown in association with Zea mays in the Quechua region of the Peruvian Andes     

Gregorio Arone  Constantino Calderón  Silvia Moreno  Eulogio J. Bedmar 《Biology and Fertility of Soils》2014,50(1):185-190

Peasants of the Quechua region of the Peruvian Andes use chacras to grow maize (Zea mays) in innate association with bur clover (Medicago hispida). From a total of 25 bacterial strains isolated from root nodules of bur clover grown in soils from chacras in Allpas (Acobamba, Peru) 7 clustered into 6 Repetitive extragenic palindromic-polymerase chain reactions (REP–PCR) groups. The nearly complete 16S rRNA gene sequence from the representative strains AP1, AP15, AP28, AP29, AP37, and AP70 showed they were closely related to members of the genus Ensifer of the Alphaproteobacteria. Sequencing of the housekeeping atpD, glnII, and recA and the symbiotic nodC genes from each of the six strains revealed they all were similar to those of strains included in Ensifer medicae. The remaining 18 strains were distributed into 8 REP–PCR groups and analyses of the 16S rRNA gene sequences showed that the isolates belong to several phylogenetic groups, being closely related to species of genera Kaistia, Pseudomonas, Achromobacter, Stenotrophomonas, Xanthomonas, Sphyngopyxis, Duganella, and Rheinheimera.  相似文献   

Shrub biomass accumulation and growth rate models to quantify carbon stocks and fluxes for the Mediterranean region     

Maria Pasalodos-Tato  Ricardo Ruiz-Peinado  Miren del Río  Gregorio Montero 《European Journal of Forest Research》2015,134(3):537-553

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Comparison of iron bioavailability from 15 rice genotypes: studies using an in vitro digestion/caco-2 cell culture model   总被引：5，自引：0，他引：5  

Glahn RP  Cheng Z  Welch RM  Gregorio GB 《Journal of agricultural and food chemistry》2002,50(12):3586-3591

An in vitro digestion/Caco-2 model was used to compare iron bioavailability from 15 selected Fe-dense and normal genotypes of unpolished rice from the International Rice Research Institute. Iron uptake was determined using Caco-2 cell ferritin formation in response to exposure to a digest of the cooked rice. Iron bioavailabilities from all rice genotypes were ranked as a percent relative to a control variety (Nishiki). Iron concentration in the rice samples ranged from 14 to 39 microg/g. No correlation was observed between Fe uptake and grain-Fe concentration. Furthermore, phytic acid levels were not correlated with Fe bioavailability. Genotypes with low Fe bioavailability (Tong Lan Mo Mi, Zuchein, Heibao, and Xua Bue Nuo) were noticeably more brown to purple in color. The results suggest that certain unknown compounds related to rice grain color may be a major factor limiting Fe bioavailability from unpolished rice.  相似文献   

Influence of mass and volume of ruminal contents on voluntary intake and digesta passage of a forage diet in steers.     

M A Schettini  E C Prigge  E L Nestor 《Journal of animal science》1999,77(7):1896-1904

To assess the influence of volume and mass of ruminal contents on voluntary intake and related variables, five ruminally cannulated steers (550 kg) were fed a low-quality forage diet (43.1% ADF, 8.1% CP) in a 5 x 5 Latin square experiment. Mass and volume of ruminal contents were altered by adding varying numbers and weights of filled tennis balls (6.7-cm diameter) to the rumen immediately before the initiation of each experimental period. Treatments consisted of 0 balls (control), 50 balls with a 1.1 specific gravity (SG), 100 balls with a 1.1 SG, 50 balls with a 1.3 SG, and 100 balls with a SG of 1.3. The total volume of balls was 7.25 and 14.5 L for 50 and 100 balls, respectively. The total weight of balls was 8.5 and 17 kg for 50 and 100 balls with a 1.1 SG and 10.75 and 21.5 kg for 50 and 100 balls with a 1.3 SG, respectively. Daily DMI was 8.3, 7.3, 7.0, 6.5, and 6.0 kg for control; 50, 1.1 SG; 50, 1.3 SG; 100, 1.1 SG; and 100, 1.3 SG, respectively. Addition of balls to the rumen reduced (P < .01) DMI. Increasing the number (P < .01) and SG (P <. 01) of the balls decreased DMI further. However, digestibilities of DM, NDF, ADF, and CP were not influenced by treatment. Increasing the number of balls in the rumen increased (P < .05) rate of passage of digesta from the rumen, but increasing SG of the balls did not alter rate of passage. There was a treatment x hour interaction (P < .05) in the proportion of ruminal digesta with a functional specific gravity (FSG) less than 1.1, which decreased with time after feeding for the control but increased with time after feeding for other treatments. Ruminal passage rate of inert particles added in the rumen of different SG (1.1 and 1.3) and length (1 and 3 mm) decreased (P < .05) as SG of the balls increased. Mean fecal particle size was greater for those treatments with the heavier balls. Both the number and SG of balls (P < .10) influenced total VFA, and total concentrations were greater for the control and for the 1.1 SG than for the 1.3 SG treatments.  相似文献   

Possible genetic variation in resistance of turkeys to erysipelas and fowl cholera     

Y M Saif  K E Nestor  R N Dearth  P A Renner 《Avian diseases》1984,28(3):770-773

Natural disease outbreaks of erysipelas and fowl cholera occurred in several lines of turkeys maintained for genetic studies. There were line differences in mortality during both outbreaks, suggesting that there is genetic variation in resistance to these diseases. A line developed by selection for increased egg production had a higher mortality rate from fowl cholera than did the randombred control line from which it was developed. Both the egg line and its control line had a lower mortality rate in the erysipelas outbreak than did a line selected for increased growth rate. Both diseases induced high mortality in a line selected for increased growth.  相似文献   

Will nutrient-efficient genotypes mine the soil? Effects of genetic differences in root architecture in common bean (Phaseolus vulgaris L.) on soil phosphorus depletion in a low-input agro-ecosystem in Central America     

Amelia Henry  Nestor F. Chaves  Peter J.A. Kleinman  Jonathan P. Lynch 《Field Crops Research》2010,115(1):67-78

Crop genotypes with root traits permitting increased nutrient acquisition would increase yields in low fertility soils but have uncertain effects on soil fertility in the long term because of competing effects on nutrient removal vs. the soil conserving effects of greater crop biomass. This study evaluated the relative importance of phosphorus loss in crop extraction vs. phosphorus loss in soil erosion as influenced by genetic differences in root shallowness and therefore phosphorus uptake in common bean (Phaseolus vulgaris L.). Six recombinant inbred lines of varying root architecture and two commercial genotypes of bean were grown in unfertilized, steeply sloped (32%), low phosphorus (5.8 mg kg^?1, Fe-strip) Udults in Costa Rica. Fertilized (60 kg total phosphorus ha^?1) plots of commercial genotypes were also included in the study. Runoff was monitored throughout the bean growing season in 2005 and 2006, and in 2006, monitoring continued through the maize growing season. Phosphorus removed in plant biomass at harvest through the 2006 bean–maize crop cycle averaged 7.3 kg ha^?1 year^?1, greatly exceeding phosphorus loss due to erosion (0.15–0.53 kg ha^?1 year^?1) in unfertilized plots. In fertilized bean plots, total biomass phosphorus averaged 6.32 kg ha^?1 year^?1 and total eroded phosphorus averaged 0.038 kg ha^?1 year^?1, indicating rapid sorption of fertilizer phosphorus. Shoot growth of several recombinant inbred lines under low phosphorus was comparable to that of fertilized commercial genotypes, illustrating the effectiveness of selection for root traits for improving plant growth in low-phosphorus soils. Genotypic differences in root architecture of recombinant inbred lines led to 20–50% variation in groundcover by shoots, which was associated with 50–80% reduction in sediment loss. This study demonstrates that root architecture traits can affect nutrient cycling at the agro-ecosystem level, and that integrated nutrient management strategies are necessary to avoid soil nutrient depletion.  相似文献   

Financial feasibility of implementing regulated and sustained deficit irrigation in almond orchards     

Francisco Alcon  Gregorio Egea  Pedro A. Nortes 《Irrigation Science》2013,31(5):931-941

This study aims to assess the long-term economic viability of deficit irrigation (DI) strategies in almond trees (cv. Marta) grown in a semiarid area (southeast Spain). A discounted cash flow analysis (DCFA) was performed to determine the profitability of the different irrigation regimes. Four irrigation treatments were evaluated over the first 6 years of an almond plantation: (1) full irrigation (FI); (2) regulated deficit irrigation (RDI) receiving 40 % ETc during kernel-filling and 100 % ETc during the remainder of the growing season; (3) mild-to-moderate sustained deficit irrigation (SDI_mm), irrigated at 75 % ETc (first half of the experiment) and 60 % ETc (second half of the experiment) over the entire growing season; and (4) moderate-to-severe SDI (SDI_ms), irrigated at 60 % ETc (first half of the experiment) and 30 % ETc (second half of the experiment) over the whole growing season. Irrigation water profit was mainly determined by the annual volume of irrigation water applied (water costs are around 50 % of variable costs). DCFA indicates that RDI and SDI_mm are the most economically feasible treatments, whereas FI and SDI_ms presented a similar degree of profitability over the 6-year period. Simulation outputs derived for the whole useful life of the investment indicate that SDI_mm would be the most suitable irrigation treatment to be adopted by almond farmers in the study area. We conclude that in a context of water scarcity, DI is a financially feasible alternative to FI.  相似文献   

Antioxidant activity of Rhizophora mangle bark     

Sánchez J  Melchor G  Martínez G  Escobar A  Faure R 《Fitoterapia》2006,77(2):141-143

The antioxidant activity of Rhizophora mangle bark aqueous extract and its majoritary component and high molecular weight polyphenols' fraction were studied using deoxyribose assay. The total extract and its fraction showed scavenging activity of hydroxyl radicals and hability to chelate iron ions.  相似文献   

Sectional anatomic and magnetic resonance imaging features of the head of juvenile loggerhead sea turtles (Caretta caretta)     

A Arencibia  MR Hidalgo  JM Vázquez  S Contreras  G Ramírez  J Orós 《American journal of veterinary research》2012,73(8):1119-1127

Objective-To compare anatomic features of cross-sectional specimens with those of MRI images of the heads of loggerhead sea turtles (Caretta caretta). Animals-5 cadavers of juvenile female loggerhead sea turtles. Procedures-Spin-echo T1-weighted and T2-weighted MRI scans were obtained in sagittal, transverse, and dorsal planes with a 0.2-T magnet and head coil. Head specimens were grossly dissected and photographed. Anatomic features of the MRI images were compared with those of gross anatomic sections of the heads from 4 of these turtles. Results-In the MRI images, anatomic details of the turtles' heads were identified by the characteristics of signal intensity of various tissues. Relevant anatomic structures were identified and labeled on the MRI images and corresponding anatomic sections. Conclusions and Clinical Relevance-The MRI images obtained through this study provided valid information on anatomic characteristics of the head in juvenile loggerhead sea turtles and should be useful for guiding clinical evaluation of this anatomic region in this species.  相似文献