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This study focused on the reproduction effectiveness of 10 breeding strains of common carp (Polish strains 2, 3, 6; Hungarian strains 0, W, 7; Lithuanian strain B; French strain F; Israeli strain D and Yugoslavian strain J) after stimulation of ovulation with carp pituitary homogenate or Ovopel. The percentage of females with recorded ovulation became higher after Ovopel treatment in as many as eight breeding strains (2, 3, 6, 0, W, B, F, D). The interaction between the spawning agent and the breeding strain was statistically significant (P ≤ 0.05) for the mass of spawn and non‐significant for traits determining the quality of eggs. Among the 10 breeding strains, in 4 (3, 7, B, J) the least‐squares means (LSM) for the weight of egg (g) were higher for fish stimulated with Ovopel. Among the strains tested, in seven (3, W, F, J, 2, 7, B), the LSM for the percentage of living embryos after 36 h incubation were higher for fish treated with Ovopel. The evaluation of reproduction effects based on the values of such parameters as the percentage of ovulating females, weight of eggs (g) and the percentage of live embryos (36 h) showed that after Ovopel treatment the poorer effects were obtained only for strains 6, 0 and D.  相似文献   
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Forest transformation from coniferous monocultures to mixed stands is being promoted worldwide, including the introduction of fast-growing broadleaved tree species within native stands. Here, we studied how enrichment of temperate European Scots pine (Pinus sylvestris) forest by North-American northern red oak Quercus rubra impacted macronutrient concentrations in two long-lived and dominant components of the forest understory: bilberry Vaccinium myrtillus and lingonberry V. vitis-idaea. Study sites were located in forest complexes (central Poland) which occupy continuously reforested lands (hereafter ancient forests) as well as post-agricultural lands (recent forests), all suitable for mesic pine forests. Samples of bilberry and lingonberry leaves, stems, and fruits were collected in pine stands and in adjacent Scots pine-red oak stands, in both ancient and recent forests. Concentrations of macronutrients (C, N, P, K, Ca, S, and Mg) in aboveground biomass components were analysed using standardized chemical procedures. The study revealed intra- and interspecific (bilberry vs. lingonberry) differences in concentrations of all nutrients in leaves, stems, and fruits, except for invariable C concentrations. Macronutrient accumulations in plants were decreased by land-use discontinuity and favoured by enrichment of tree stands by Q. rubra. The estimated macronutrient pools were much higher for V. myrtillus than V. vitis-idaea in all forest types studied. They were lower in forests enriched with Q. rubra, both ancient (up to 25.5% for bilberry and 99.9% for lingonberry) and recent (46.9% and 99.9%, respectively), as well as in recent pine forest (46.6% and 81.1%, respectively) than in ancient pine forest. Higher K and S pools (39.3% and 6.5%, respectively) noted for bilberry in an ancient forest with Q. rubra were exceptions. Despite more effective accumulations of elements at the species level, macronutrient pools of Vaccinium myrtillus and V. vitis-idaea decreased significantly in the presence of introduced Q. rubra due to negative impacts of this broadleaved tree on bilberry and lingonberry cover and biomass. Therefore, the limitation of alien Q. rubra planting in sites of mesic pine forest with the abundant occurrence of V. myrtillus and/or V. vitis-idaea is recommended.

Graphic abstract
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以分离自西藏那曲县罗玛镇传统发酵酸牦牛奶中的乳酸乳球菌乳脂亚种(Lactococcus lactis subsp.Cremoris)IMAU60064为试验菌株,研究其最佳的培养条件。对碳源、氮源、缓冲盐等培养基成分及培养条件进行优化,并采用响应面法对优选的碳源、氮源和缓冲盐类的组成含量进行优化,得到IMAU60064的增殖培养基为:葡萄糖23g/L、大豆蛋白胨11g/L、牛肉膏11g/L、胰蛋白胨5g/L、NaAC1.8g/L、K2HP041.2g/L、柠檬酸钠1.2g/L、MgSO4·7H200.4g/L、MnSO4·5H2O54mg/L、L-半胱氨酸盐酸盐0.5g/L、吐温80为1g/L。Lactococcus lactis subsp.cremorisIMAU60064在此增殖培养基中经30℃,14h培养活菌数可达到3.26×10^8cFu/mL,比在MRS中(6.54×10^7CFU/mL)提高近5倍。  相似文献   
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A series of per-O-methylated flavonoid di- and tri-glycosides, linked with 1-2 and/or 1-6 glycosidic bonds between sugar rings that were isolated from different plant materials were analyzed. It was demonstrated that the fragmentation behavior of permethylated flavonoid glycosides is dependent on the glycosidic bond placement between sugars. Y(n) type fragment ions, created after glycosidic bond cleavage with oxygen retention on sugar at the reducing end for permethylated compounds, were observed in the normal and linked-scan mass spectra recorded for alpha(1-2) bonded conjugates of flavonoid di- and tri-glycosides. Moreover, for alpha (1-6) linked glycosides, Y fragments created after rearrangement and elimination of internal sugar residues were observed in addition to Y(n) type ions, but these fragment ions were not registered in normal desorption ionization spectra. This second type of fragmentation was also reported previously in collision-induced dissociation tandem mass spectrometry (CID MS/MS) spectra of some oligosaccharides and flavonoid glycosides, but their presence was independent of the glycosidic bonds placement between sugar rings.  相似文献   
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The dimethylformamide extracts from sewage sludges from a chosen sewage — treatment plant in highly industrialized region of Poland were investigated. Using the column chromatography with Al2O3 and silicic acid as the stationary phases, the fraction of azaarenes has been separated. GC-MS analysis of azaarenes fraction made it possible to identify 10 azaarenes and several of their alkyl derivatives, which dominate in the organic matter extracted from sewage sludges. The silicic acid column chromatography in connection with the reduction of nitroarenes and derivatization with pentafluoropropionic acid anhydride yielded an enriched nitrofraction. Nitroarenes present in this fraction as amide derivatives were also analysed by GGMS method. There was found presence of 3 nitroarenes and their methyl derivatives.  相似文献   
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Purpose

Suspended particulate matter (SPM) plays a crucial role in the transport of natural and anthropogenic substances. However, obtaining a representative sample and a substantial amount of SPM in rivers, where the flux and quantity of SPM are highly episodic, can be a challenging task. To collect a sufficient quantity of SPM for detailed sedimentological and geochemical analysis, a time-integrated mass flux sampler (TIMS) was used for the sampling in a medium size river (the Sava River, Croatia).

Materials and methods

Sampling was conducted in August and October 2014, and February and May 2015 under different discharge conditions. The SPM collected by TIMS was characterized with respect to its particle size distribution (PSD), mineral content, and geochemical composition.

Results and discussion

PSD analysis identified silt as a dominant size fraction in all samples except in May 2015 when sand prevailed; subsequent chemical dispersion of samples revealed flocculation as the main factor responsible for the resulting PSD. The mineralogical composition of the SPM was quite constant (quartz, calcite, dolomite, feldspar, illite/muscovite, kaolinite), but the contribution of particular mineral varied depending on the sampling period. In May 2015, unusually high calcite content was determined. Though the dominant source is still uncertain, a portion of calcite is likely detrital in origin. Geochemical analyses of collected material revealed significant anthropogenic input of ecotoxic elements (Ni, As, Cr, Pb, Bi, Cd, Zn, Sb) primarily associated with the fine fraction of the Sava River SPM.

Conclusions

A considerable amount of the SPM was collected by TIMS, both during high and low river discharge. Sedimentological analyses of the Sava River SPM suggested the input of material from various sources during different river regimes. Geochemical composition of the SPM followed its sedimentological characteristics—preferential adsorption of trace elements to fine-grained clay mineral particles was documented. Some processes inside TIMS were observed during this investigation—the suspended material captured inside the sampler underwent additional changes. The flocculation of the colloidal material instigated by algal bloom was observed.

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The effect of sodium and potassium concentrations as well as optimal pH on the motility of common carp Cyprinus carpio L. sperm during short-term storage in artificial seminal plasma (ASP) was investigated. Sperm was collected from individual males (n?=?5) and each sample diluted tenfold (1:9) in ASP (sperm:extender) containing 2 mM CaCl2, 1 mM Mg2SO4 and 20 mM Tris at pH 8.0 and supplemented by the following concentrations of sodium and potassium (mM/mM): 0/150, 20/130, 40/110, 75/75, 110/40, 130/20 and 150/0. The osmolality of all ASP variants was set at 310 mOsm kg?1. Sperm motility was measured using a CASA system during 72 h of storage. Immediately after dilution, sperm motility was high (90%) both in each variant and in the control group (fresh sperm). After 72-h storage, the highest sperm motility was noted in ASP containing 110 mM NaCl and 40 mM KCl. No differences were found in the motility of samples preserved within the pH range of 7.0–9.0. Our data suggest that for the short-term storage of common carp sperm, whereas the pH of the solution does not play a crucial role, a specific potassium concentration of around 40 mM is required.  相似文献   
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