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1.
Changes in fatty acids profile,monosaccharide profile and protein content during batch growth of Isochrysis galbana (T.iso) 下载免费PDF全文
Asma Gnouma Irina Sadovskaya Anissa Souissi Khaled Sebai Amel Medhioub Thierry Grard Sami Souissi 《Aquaculture Research》2017,48(9):4982-4990
To investigate the nutritional value of the marine micro‐alga Isochrysis galbana Tahitian Isochrysis strain (T.iso) as an alternative feed for aquaculture during culture age, its biochemical composition was studied under autotrophic and controlled culture conditions at different growth stages: exponential phase, early and late stationary phases and decay phase. Analysis showed that C14:0, C16:0, C16:1, C18:4 (n‐3) and C22:6 (n‐3) were the most abundant fatty acids in this alga at different growth stages. The highest values of monounsaturated fatty acids were recorded at the late stationary and the decay phases. However, the highest levels of polyunsaturated fatty acids were observed at the early stationary phase. At all growth stages, I. galbana (T.iso) contained arabinose, xylose, mannose, galactose and glucose. Glucose represented the main sugar, and its content per dry alga biomass weight increased with increasing age of the culture and reached about fourfold in the decay phase. The maximum protein content was also observed during this last phase. 相似文献
2.
Fernando LóPEZ-GATIUS Irene LóPEZ-HELGUERA Fabio DE RENSIS Irina GARCIA-ISPIERTO 《The Journal of reproduction and development》2015,61(5):465-471
This study compared the responses shown by lactating dairy cows to four different P4-based protocols for AI at estrus. Cows with no estrous signs 96 h after progesterone intravaginal device (PRID) removal were subjected to fixed-time AI (FTAI), and their data were also included in the study. In Experiment I, follicular/luteal and endometrial dynamics were assessed every 12 h from the beginning of treatment until AI. The estrous response was examined in Experiment II, and fertility was assessed in both experiments. The protocols consisted of a PRID fitted for five days, along with the administration of different combinations of gonadotropin releasing hormone (GnRH), equine chorionic gonadotropin and a single or double dose (24 h apart) of prostaglandin F2α. In Experiment I (40 cows), animals receiving GnRH at the start of treatment showed a significantly higher ovulation rate during the PRID insertion period while estrus was delayed. In Experiment II (351 cows),
according to the odds ratios, cows showing luteal activity at the time of treatment were less likely to show estrus than cows with no signs of luteal activity. Treatment affected the estrous response and the interval from PRID removal to estrus but did not affect conception rates 28–34 days post AI. Primiparous cows displayed a better estrous response than multiparous cows. Our findings reveal acceptable results of 5-day P4-based protocols for AI at estrus in high-producing dairy cows. Time from treatment to estrus emerged as a good guide for FTAI after a 5-day P4-based synchronization protocol. 相似文献
3.
Maria Holmberg Anu Akujärvi Saku Anttila Lauri Arvola Irina Bergström Kristin Böttcher Xiaoming Feng Martin Forsius Inese Huttunen Markus Huttunen Yki Laine Heikki Lehtonen Jari Liski Laura Mononen Katri Rankinen Anna Repo Vanamo Piirainen Pekka Vanhala Petteri Vihervaara 《Landscape Ecology》2015,30(3):561-577
4.
Irina Kouplevatskaya-Buttoud 《Small-Scale Forestry》2009,8(2):231-247
Changes in small-scale forest governance as a reaction to global changes are viewed from the system dynamics perspective,
focused on two levels of dynamic systems: the policy system with sets of interactions at the national level and the management
system at the local level. These interactions are considered through permanent adaptation and re-shaping of stakeholders’
networks and positions provoking further changes in the systems. Empirical evidence has been obtained from two case studies
related to small-scale rural forestry in distinct contexts—France (the Territorial Forestry Charters) and Kyrgyzstan (collaborative
forest management and leasing of forest plots)—and viewed through a theoretical framework of social-political systems dynamics.
The changes caused by the systems’ capacity for adaptability and resilience are expressed through a double spiral of decision-making,
characterising the interactions between national policies and local management practices. The analysis leads to a conclusion
that changes are basically determined by the formal and informal stakeholders’ strategies developed in a specific context
and their mutual adaptation aimed at system resilience.
相似文献
Irina Kouplevatskaya-ButtoudEmail: |
5.
6.
Modelling of snowmelt erosion and sediment yield in a small low-mountain catchment in Germany 总被引:1,自引:0,他引:1
Temporal variability and spatial heterogeneity of surface runoff generation triggers the dynamics of source areas of sediment and sediment-associated nutrient transport. Reliable modelling of hydrological special situations i.e. snowmelt is of high importance for the quality of erosion and sediment yield modelling. Data from the research catchment Schäfertal demonstrate the individuality of snowmelt events in terms of runoff coefficient and delivery ratio. This 1.44 km2 low mountain catchment is characterised by a high portion of arable land with a winter grain/winter rape crop rotation. The integrated winter erosion and nutrient load model (IWAN) considers these dynamic aspects by coupling a hydrological model with a sediment load model. Cell size of this raster-based approach is 10 × 10 m2. Additionally, snowmelt rill erosion is simulated with a newly developed physically based model that is firstly applied on a catchment scale. A sensitivity analysis of this model system component demonstrates the plausibility of the model approach and the overall robustness of the model system IWAN. The results of the long-term hydrological modelling from 1991 to 2003 are reliable and form the basis for the simulation of six snowmelt events which were observed in the Schäfertal catchment. The estimated total runoff volumes for these events match the observations well. The modelled overland runoff coefficients vary from 0.001 to 0.72. The mean values of cell erosion, which were modelled with one set of parameters for all six events range from 0.0006 to 0.96 t ha− 1. The total modelled erosion for the events with unfrozen soil and low amount of surface runoff is of a factor 50 below those with partly frozen soil. In addition to these distinctions, the major differences are caused by flow accumulation in shallow depressions in variable parts of the catchment. However, the validation of these results on the single event scale is restricted due to limited spatial data. Total simulated sediment yield at the catchment outlet was as high as 13.84 t which underestimates the observed values, with the exception of one event. Oversimplification of the modelled channel processes may be a reason. The temporal variability and spatial heterogeneity of the surface roughness parameter, which was identified to be sensitive, also causes uncertainty in the parameter estimation. Despite these findings, the model system IWAN was applied successfully on the catchment scale and the simulated results are reliable. 相似文献
7.
Stepanov I Carmella SG Hecht SS Duca G 《Journal of agricultural and food chemistry》2002,50(10):2793-2797
Tobacco-specific nitrosamines (TSNA) are among the most important and abundant strongly carcinogenic agents in unburned tobacco. It has been established that 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) induces lung tumors in rodents independent of the route of administration. N'-Nitrosonornicotine (NNN) causes tumors of the esophagus and nasal cavity in rats, lung in mice, and respiratory tract in hamsters. Although the manufacturing of cigarettes is an important domain of Moldovan industry, there are no reports in the literature on TSNA analysis in Moldovan tobacco. The main purpose of the present study was an initial evaluation of TSNA levels in Moldovan cigarette tobacco. Eighteen brands of Moldovan cigarettes, representing 78% of all brands produced in Moldova, were analyzed. Four TSNA-NNN, NNK, N'-nitrosoanatabine (NAT), and N'-nitrosoanabasine (NAB)-were analyzed by gas chromatography with nitrosamine selective detection (GC-TEA). Levels of TSNA in most Moldovan cigarettes were substantially lower than in American brands. Mean levels of NNN in three commercial American brands were 3.32 +/- 0.88 (SD) microg/g as compared to 0.579 +/- 0.548 microg/g, range 0.093-2.09 microg/g (N = 18), in the cigarettes produced in Moldova. For NNK and NAT, mean levels in the American brands were 1.57 +/- 0.178 and 1.99 +/- 0.579 microg/g, respectively, while the corresponding values for Moldovan cigarettes were 0.193 +/- 0.089, range 0.104-0.484 microg/g, and 0.160 +/- 0.114 microg/g, range 0.055-0.481 microg/g. The highest levels of NNN-1.10-2.09 microg/g-were observed in "American type" cigarettes manufactured from high-quality tobacco. The results of this study should be useful in heightening the awareness of the dangers of smoking in Moldova and can be envisioned as the initial step in the control of tobacco-related cancer in this republic. 相似文献
8.
Effect of microrelief on the spatial variability of carbon content of a Podzoluvisol in a long term field trial The relationship between microrelief and spatial distribution and variability of the soil Ct-content was investigated in a long term field experiment with different fertilizer and herbicide treatments near Moscow. Only 20% of the Ct-variability were related to agricultural factors. In order to analyse the influence of the microrelief on soil Ct-content the relief was formalized. This formalization included the calculation of the local inclination, local water gathering area and local relative intensity of the temporary water streams, while distinguishing between convex and concave relief forms. Relief forms of different order were identified by kriging with different distances between the block centers. The parameters of the formalized relief were compared with the Ct-content of the soil by means of semivariograms and correlations. Through combination of relief parameters, it was possible to divide the field into different elements characterized by different correlations and effect types. The water gathering relief forms with maximal values of the relative intensity of the water streams and the arched forms with increasing intensity reduced soil Ct-content. Ct-accumulation occurred at transit positions between the convex and concave relief forms with medium intensity. 相似文献
9.
Stepanov I Hecht SS Mirvish SS Gonta M 《Journal of agricultural and food chemistry》2005,53(20):8082-8086
While previous studies have evaluated levels of tobacco-specific nitrosamines (TSNA) and total N-nitroso compounds (NOC) in tobacco, there are no reports in the literature on TSNA and total NOC in the same tobacco products. We compared levels of TSNA, total NOC, and NOC precursors (NOCP) in tobacco of cigarettes purchased in Moldova and in some tobacco types commonly used for the manufacturing of Moldovan cigarettes. Cigarette tobaccos included those from non-Moldovan, traditional Moldovan, and blended Moldovan cigarettes. The results demonstrate that tobacco of non-Moldovan cigarettes contains higher TSNA and NOC levels (mean, 16 and 63 nmol/g tobacco, n = 6) than that of Moldovan cigarettes (mean, 5 and 23 nmol/g tobacco, n = 25). TSNA and NOC levels were also generally higher in tobacco of blended than in traditional Moldovan cigarettes. NOCP levels in Moldovan and non-Moldovan cigarette tobacco were similar as follows: 29000 +/- 30000 and 33000 +/- 28000 nmol/g tobacco (mean +/- SD). Total NOC were strongly correlated with total TSNA levels (r = 0.66; P < 0.0001). These findings demonstrate that current technologies involved in the manufacture of some blended cigarettes create conditions that favor N-nitrosation of alkaloids and other tobacco constituents. 相似文献
10.
Vvedenskaya IO Rosen RT Guido JE Russell DJ Mills KA Vorsa N 《Journal of agricultural and food chemistry》2004,52(2):188-195
Flavonoids were extracted from cranberry powder with acetone and ethyl acetate and subsequently fractionated with Sephadex LH-20 column chromatography. The fraction eluted with a 60% methanol solution was composed primarily of phenolic constituents with maximum absorbance at 340 nm. A high-performance liquid chromatography procedure was developed, which resolved 22 distinct peaks with UV/vis and mass spectra corresponding to flavonol glycoside conjugates. Six new constituents not previously reported in cranberry or in cranberry products were determined through NMR spectroscopy to be myricetin-3-beta-xylopyranoside, quercetin-3-beta-glucoside, quercetin-3-alpha-arabinopyranoside, 3'-methoxyquercetin-3-alpha-xylopyranoside, quercetin-3-O-(6' '-p-coumaroyl)-beta-galactoside, and quercetin-3-O-(6' '-benzoyl)-beta-galactoside. Quercetin-3-O-(6' '-p-coumaroyl)-beta-galactoside and quercetin-3-O-(6' '-benzoyl)-beta-galactoside represent a new class of cranberry flavonol compounds with three conjugated components consisting of a flavonol, sugar, and carboxylic acid (benzoic or hydroxycinnamic acids). This is also the first report identifying quercetin-3-arabinoside in both furanose and pyranose forms in cranberry. Elucidation of specific flavonol glycosides in cranberry is significant since the specificity of the sugar moiety may play a role in the bioavailability of the flavonol glycosides in vivo. 相似文献