Effect of Two Natural Carotenoid Sources in Diets for Gilthead Seabream,Sparus aurata,on Growth and Skin Coloration

To improve the unnatural fade-pigmented skin of cultivated gilthead seabream, Sparus aurata, (if shown) the present study was initiated. The effects of either red bell-pepper (Capsicum annum) meal or carrot (Daucus carota) meal as a natural dietary carotenoid source, on growth and skin coloration of gilthead seabream growers were investigated. A basal/control diet (D1/CTR) was firstly formulated to contain 48% crude protein and 14% lipids, with no added-carotenoids. With this basal diet, two other test diets were similarly prepared and supplemented each with about 40mg/Kg total carotenoids from either red-pepper meal (D2) or carrot meal (D3). In a feeding trial, fish (mean IW, 94.86±0.3g) were fed one of the three diets (D1, D2, D3), in triplicates for each treatment, for 6 weeks in light-blue background PVC tanks supplied with natural seawater flow. Total carotenoids content of skin was determined spectrophotometerically at initiation and end of the experiment. Neither growth nor feed utilization were significantly (P<0.05) affected by the red pepper-added diet (D2) as compared to CTR diet. However, the carrot fed fish recorded the lowest and significant (P<0.05) weight gain (g/fish) and specific growth rate (SGR, %/d) among dietary treatments. There were no considerable (P>0.05) differences in major nutrients composition between fish fed the experimental diets. Total carotenoids content was significantly (P<0.05) increased, in the skin-opercle area, of fish fed the red pepper diet (D2) as compared to initial fish and to either carrot fed fish or CTR fish. Results have suggested that gilthead seabream can effectively bio-absorb natural carotenoid pigments (mainly capsansin and capsorbin) in red-pepper but not in carrot (mainly β-and α-carotene).     

Determination of water requirement, single and dual crop coefficients of black cumin (Nigella sativa L.) in a semi-arid climate

Crop coefficients of some plants have been provided by the Food and Agricultural Organization albeit crop coefficients for different medicinal plants such as black cumin (Nigella sativa L.) have not been determined so far. Experiments were carried out during 2 years (2010 and 2011) to determine the water requirements, single and dual crop coefficients of black cumin using drainable lysimeter in a semi-arid region. In this study, black cumin water requirement was determined to be 724 mm by water balance method. The reference evapotranspiration was estimated by Penman–Monteith method. Finally, single and base crop coefficients for initial, development, middle and final stages of black cumin growth were determined to be as 0.59, 0.91, 1.29, 0.78 and 0.24, 0.71, 1.09 0.78, respectively. In order to estimate black cumin evapotranspiration by meteorological parameters, multiple regression models were presented. The results of the study showed that the determination of black cumin water requirements with dual crop coefficients had a less difference as compared to the results obtained from regression model. The total dry matter produced was 9.48 kg/ha per mm of irrigation water applied, seed yield was 3.10 kg/ha per mm of irrigation water applied, and oil content was 31 %.     

A Nondestructive,Remote Sensing-Based Estimation of the Economic Value of Aboveground Temperate Forest Biomass (Case Study: Hyrcanian Forests,Nowshahr-Iran)

ABSTRACT

Background: Traditional field-based methods of measurement of biomass and carbon storage face difficulty in collecting time-consuming and expensive, suggests the use of remote sensing-based techniques. It estimates the economic value of the aboveground biomass (AGB) using satellite remote sensing across the Hyrcanian forests of Iran. Methods: The Landsat-8 OLI sensor data were combined with field-based allometric information of 186 circular sample plots. The AGB was calculated at the plot level using the collected data and specific volumetric mass for species in the studied area. It was followed by calculating the carbon storage using a 50% carbon coefficient and the photosynthesis equation at the forest parcel level. Model results using the random forest and support vector machines. The carbon sequestration value was calculated with USD 25.3 as a shadow value of carbon in 2014 and using the replacement cost approach. Results: The highest performances achieved by RF for biomass, carbon storage and the carbon storage value (Iranian Rials of 0.67% and 16%, respectively). The value was derived once at the plot level of 12.22 million IRR (370.43 USD) per ha. In addition, at the parcel level, which resulted in an estimated value of 12.87 million IRR (390.24 USD) per ha.     

Asian spiderflower (Cleome viscosa) germination ecology in southern Iran

Cleome viscosa is one of the most important weeds of warm‐season crops in southern Iran. Laboratory experiments were conducted to assess the impact of environmental factors on seed germination of C. viscosa . Freshly harvested seeds exhibited dormancy that was relieved (>90%) after immersion for 20 min in concentrated sulfuric acid. Regardless of the temperature regime, the final percentage of germination in light/dark (69.3%) was significantly higher than in complete darkness (58.3%). The optimum temperature for germination was 35/25°C in both light and dark. No germination was observed at constant temperatures of either 15 or 45°C. The thermal thresholds for seed germination, the base (T _b) and the mean ceiling germination temperatures (T _c(50)) were estimated to be 18.8 and 39.9°C, respectively. A base water potential ( Ψ _b(50) ) of ?0.96 MPa was identified for C. viscosa seeds. The response threshold of C. viscosa to reduce 50% of maximum germination for salinity was estimated to be 255 mM. Seeds that were placed on the soil surface had the highest percentage of seedling emergence (77.3%), and no seedlings emerged from seeds placed at a depth of 6 cm. The findings of this study could help to improve the integrated weed management strategies for this species.     

Potential habitat modeling for reintroduction of three native plant species in central Iran

Potential habitat modeling of endemic species is an appropriate method to maintain biodiversity,ecosystem function and rehabilitation of rangeland ecosystems.Astragalus caragana,A.cyclophyllon and A.podolobus are endemic in Iran's rangelands and some neighboring countries.The three native species could endure environmental stresses due to their distinctive ecophysiological characteristics.They play important roles in sustainable pastures production,recreation and improvement.They suffer severe threat from many factors including;grazing,agriculture and invasive exotic species.We analyzed the potential habitat of three native plant species in central Iran basing on the grid map with the resolution of 1-km.We used inventory records from field surveys,herbarium collections and 22 environmental factors to explore the environmental influences on given species distribution by Maximum entropy(Maxent) model.Maxent is a species distribution model that uses species occurrence and environmental data for predicting potential species.The results of our study indicated species occurrence has strong correlation with environmental factors such as mean temperature of wettest season,elevation and precipitation of coldest season.We evaluated the model accuracy by AUC(area under the receiver operating characteristic curve) based on an independent test data set.AUC values indicated the high power of Maxent to create potential habitat map(AUCA.caragana=0.988,AUCA.cyclophyllon=0.927,AUCA.podolobus=0.923).It is important to consider that AUC values tend to be lower for species that have broad distribution scope,such as A.podolobus distribution.Most suitable potential habitat distributions of the three species were predicted in the western and southwestern parts of rangelands in Isfahan province.Visual comparisons of the actual distribution map of the three species with produced Maxent maps represent a good agreement.In general,the model demonstrated that the occurrence of the given species is highly probable when the elevation is between 2,200 and 3,000 m and mean temperature of wettest season less than 3°C.This model,therefore,can be applied to recognize potential sites for rangeland reclamation projects.     

Chemical content and seasonal variation of throughfall and litterflow under individual trees in the Hyrcanian forests of Iran

We assessed the effect of seasons and the tree species velvet maple (Acer velutinum Boiss), Hainbuche hornbeam (Carpinus betulus L.) and chestnut-leaved oak (Quercus castanefolia C. A. Mey.; Fagaceae) on nutrient fluxes (Na⁺, K⁺ and Ca²⁺) in throughfall (TF) and litter flow (LF) from January 2012 to February 2013. Potassium (K⁺) and calcium (Ca²⁺) in total TF and LF over the measurement period significantly differed between 3 the species (p < 0.05). Maple and oak trees had significantly higher fluxes of K⁺ and Ca²⁺ in their TF, respectively. The average quantity of nutrients in LF was significantly higher in the leafy season than in the leafless season for all cations except for Na⁺. Under velvet maple trees, the average flux of nutrients (Na⁺, K⁺, and Ca²⁺) in TF was significantly higher than LF. Lastly, leaching of potassium (K⁺) and calcium (Ca²⁺) in LF during the measurement period was significantly lower than TF under the hornbeam trees. Our results suggest that different tree species may impact the nutrient availability and possibly the sustainability of Hyrcanian forests. Further research is needed to determine how managing different species will affect the long-term nutrient status of these forests.     

A scanner based neural network technique for color matching of dyed cotton with reactive dye

Conventional theory for color matching is Kubelka-Munk, but it fails in some situations. New intelligent procedures such as neural networks could learn the behavior of a complex system and produce accurate prediction. This paper investigates the ability of MLP (multiple layer perceptron) neural network for color matching of cotton fabric. Three reactive dyes, namely Levafix Red CA, Levafix Yellow CA and Levafix Blue CA were used for experiments. The dyed samples were scanned and L * a * b * histogram were extracted. Different neural networks were trained and tested using L * a * b * histogram of fabric’s images and also L * a * b * values (D65, 10°) of fabrics. The results were encouraging. For neural networks including the L * a * b * histogram in input vector, colorants and their concentration were predicted with a mean square error (MSE) less than 10^?5 and an average value of color difference (CMC (1:2)) less than 1.5 for approximately 80 % of testing data.     

Functionalization of graphene nanosheets and its dispersion in PMMA/PEO blend: Thermal,electrical, morphological and rheological analyses

Graphene nanoplatelet (GnP) was chemically functionalized by amine groups for improvement of compatibility in poly(methyl methacrylate) (PMMA)/poly(ethylene oxide) (PEO) blend. PMMA/PEO (90/10) nanocomposites with non-functionalized GnP and functionalized GnP (FGnP) were prepared by solution casting method. Successful grafting of amine groups on the GnP surface was confirmed by Fourier transform infrared (FT-IR) and X-ray diffraction (XRD) analysis. The Transmission electron microscopy (TEM) images showed that the dispersion state of FGnP was better than that of GnP in PMMA/PEO nanocomposites. The effects of FGnP and GnP on rheological, thermal and electrical properties of PMMA/PEO nanocomposites were investigated by various methods. The results indicated that the FGnP-based nanocomposites had higher storage modulus, glass transition temperature and thermal stability as compared to the GnP-based nanocomposites. The electrical conductivity of the nanocomposites with FGnP was better than that of GnP-based nanocomposites. The higher conductivity was attributed to homogeneous and well dispersion state of FGnP in PMMA/PEO nanocomposites.     

Prevalence of anti-<Emphasis Type="Italic">Toxoplasma gondii</Emphasis> antibodies in sport horses from Qazvin,Iran

In the present study, the prevalence of antibodies to Toxoplasma gondii in sport horses of Qazvin was examined using modified agglutination test (MAT). On 52 horse sera totally examined for anti-Toxoplasma antibodies, 37 horses (71.2%) were seropositive by MAT. Results of the present study showed a high rate of Toxoplasma infection in horses in Qazvin area. More comprehensive study on equine toxoplasmosis is recommended.     

Adsorption mechanisms of nicotine on humic acid and clay humic acid complex

The adsorption isotherm of nicotine on humic acid - surface was found to be multiphase according to the applied concentrations of nicotine. Each phase was characterized by its own change in free energy and represented a mechanism of interaction. At low concentrations, the isotherm showed a H-curve of high affinity between both reactants as a result of protonation of the pyrrolidine nitrogen atom of nicotine, the second phase was that of flat adsorption in which the nitrogen atoms of nicotine acted as electron donor. The third phase was that of the rearrangement of the nicotine from flat to side adsorption on the humic surface, after which the phase of multilayer formation followed. The adsorption on the surface of the humic acid-clay complex showed no distinct phases but an isotherm looks like the L-type, although it could not verify Langmuir's equation. Probably the isotherm was the resultant of two mechanisms one due to the adsorption of the humic acid part and the other due to the clay part in the complex. Comparison of the constants of Freundlich's equation showed that the capacity of the adsorption humic surface was greater than that of the complex.