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1.
The simulation of forest production until 2100 under different environmental scenarios and current management practices was performed using a process-based model BIOME-BGC previously parameterized for the main Central-European tree species: spruce, pine, beech and oak and adapted to include forest management practices. Climatic scenario HadCM3 used in the simulations was taken from the IPCC database created within the 3rd Assessment Report. It was combined with a scenario of CO2 concentration development and a scenario of N deposition. The control scenario considered no changes of climatic characteristics, CO2 concentration and N deposition. Simulation experiment was performed for the test region - South Bohemia - using a 1 km × 1 km grid. The actual data on the regional forest cover were aggregated for each grid cell in such a way that each cell represented an even-aged single-dominant species stand or non-forested area, and a standard management scenario depending on the stand age and species was applied to each cell. The effect of environmental variables was estimated as the difference of simulated carbon pools and fluxes in 2050 under environmental changes and under control scenario.The model simulation for the period to 2050 with only climate change under constant CO2 concentration and N deposition indicated a small decrease of NPP (median values by species reached −0.9 to −1.7% for different species), NBP (−0.3 to −1.7%) and vegetation carbon (−0.3 to −0.7%), whereas soil C slightly increased. Separate increase of N deposition gave small positive effect on carbon pools (0.8-2.9% for wood C and about 0.5% for soil C) and more expressed effect on carbon fluxes (1.8-4.3% for NPP and 1.0-9.7% for NBP). Separate increase of CO2 concentration lead to 0.6-2.4% increase of wood C pool and 0.1-0.5% increase of soil C. The positive effects of CO2 concentration and N deposition were more pronounced for coniferous than for deciduous stands.Replacement of 0.5% of coniferous plantations every year by natural broadleaved stands evoked 10.5% of increase of wood carbon pool due to higher wood density of beech and oak compared to spruce and pine, but slightly decreased soil and litter carbon pools.  相似文献   
2.
Oxidative stress is a possible source of spermatozoa function deterioration. Seminal fluid (SF) protects spermatozoa against reactive oxygen species (ROS) attack during development in testes and transit through the reproductive tract. Spermatozoa curvilinear velocity and percent of motile cells as well as changes in thiobarbituric acid-reactive substance (TBARS) content, superoxide dismutase, and catalase activity, and uric acid concentration in SF were evaluated in sterlet sperm collected from testes 24 h after hormone induction of spermiation and from Wolffian ducts at 12, 24, 36, and 60 h after hormone injection (HI). While testicular spermatozoa motility was not initiated in activating medium, Wolffian duct sperm showed low motility at 12 h, significant increase at 24 and 36 h, and decrease at 60 h. Testicular SF was characterized by the highest level of TBARS and activity of studied enzymes compared with SF from Wolffian duct sperm at 24 h post-HI. In fluid from Wolffian duct sperm, a significant increase in TBARS content was shown at 36–60 h post-HI. In contrast to testicular SF, in SF from Wolffian duct sperm, this increase was not counterbalanced by changes in the studied variables of antioxidant system. This may be the source of the observed decrease in spermatozoa motility parameters 60 h post-HI. The results may confirm a dual role of ROS in fish sperm physiology. The data with respect to decrease in sturgeon spermatozoa motility parameters at 60 h post-HI should be taken into account in artificial sturgeon propagation.  相似文献   
3.
The Atlantic cod (Gadus morhua) and red king crab (Paralithodes camtschaticus) processing wastes are massive and unutilized in the Murmansk region of Russia. The samples of skin-containing waste of Atlantic cod fillets production were hydrolyzed using enzyme preparations derived from red king crab hepatopancreases, porcine pancreases, and Bacillus subtilis bacteria. The activity of enzymes from crab hepatopancreases was significantly higher than the activity of enzymes derived from other sources. The optimal conditions of the hydrolysis process have been figured out. The samples of cod processing waste hydrolysate were analyzed for amino acid composition and molecular weight distribution. The samples of hydrolysate were used as core components for bacterial culture medium samples. The efficiency of the medium samples was tested for Escherichia coli growth rate; the most efficient sample had an efficiency of 95.3% of that of a commercially available medium based on fish meal. Substitution of medium components with those derived from industrial by-products is one of the ways to decrease a cost of a culture medium in biopharmaceutical drug production.  相似文献   
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Animal welfare and environmental protection are increasingly important. Housing systems must be found that offer animal welfare while minimizing the overall emissions of ammonia and greenhouse gases. The straw flow system is an animal friendly housing system for fattening pigs, which can be operated economically on commercial farms. Emissions from conventional slurry based pig houses have been intensively studied, but more research is needed into straw based systems. In this study, we quantified emissions of ammonia and greenhouse gases from a straw flow system with or without daily removal of slurry to an outside store. The effect of applying a solid cover during outside storage was also examined.

Emissions of NH3, N2O, CH4, and volatile organic C (VOC) from a commercial straw flow system for fattening pigs in Upper Austria were measured between June 2003 and March 2004. Emissions of CH4 during housing were 1.24 and 0.54 kg CH4 per pig place per year without and with daily manure removal, respectively. The corresponding N2O emissions amounted to 39.9 and 24.5 g N2O per pig place per year, and NH3 emissions to 2.10 and 1.90 kg NH3 per pig place per year without and with daily manure removal. Emissions of CH4, N2O and NH3, and of total greenhouse gases, from the straw flow system were lower than literature reference values for forced ventilated fully slatted floor systems. Daily removal of the manure to an outside store reduced emissions from the pig house.

Emissions during storage of pig slurry derived from a straw flow system were quantified between June 2004 and June 2005. Slurry was stored in pilot scale stores with or without a solid cover and emissions quantified by a large open dynamic chamber. The solid cover reduced NH3 and greenhouse gas emissions by 30 and 50%, respectively. During cold climatic conditions stored pig manure emitted less NH3 and greenhouse gases than when stored under warm climatic conditions. We recommend the use of separate emission factors for slurry storage in the colder and warmer periods in the national emission inventory, and the use of covers on pig slurry stores.

Overall, it is concluded that the straw flow system may combine recommendations of animal welfare and environmental protection.  相似文献   

6.
Recombinant cold-adapted strain A/HK/Otar/6:2/2010 (H3N8) constructed by the method of classic genetic reassortment, inherited the hemagglutinin and neuraminidase genes from the epizootic A/equine/Otar/764/2007 (Н3N8) virus and genes of nonglycosylated proteins from attenuation donor A/Hong Kong/1/68/162/35 (H3N2). The resulted virus was of cold-adapted (efficient growth at 25°C) and temperature-sensitive (restricted replication at 39°C) phenotype. Like the parental virus of subtype H3N2, the resulted reassortant was attenuated, with limited replication in lungs of mice (1.75 lgEID50/mL) versus replication in turbinate (2.5 lgEID50/mL). Intranasal immunization of mice with A/HK/Otar/6:2/2010 (H3N8) reassortant did not induce animal weight reduction in contrast to epizootic A/equine/Otar/764/2007 (Н3N8) virus.  相似文献   
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8.
The loss of sperm quality in sterlet (Acipenser ruthenus) due to freeze-thaw process in cryopreservation was investigated in the present study. Two antifreeze proteins (AFPI or AFPIII) were used at different concentrations of 0.1, 1, 10, and 100 μg/mL. We compared motility, curvilinear velocity, and plasma membrane integrity of fresh, cryopreserved sperm, and sperm cryopreserved in the presence of antifreeze proteins. Fresh sperm (control) had 85?±?4% motility and 160?±?2 μm/s curvilinear velocity, respectively. After cryopreservation, the motility of frozen-thawed sperm without addition of antifreeze proteins significantly decreased (44?±?9%), compared to the control. The highest motility of frozen-thawed sperm was obtained in cryopreserved sperm with addition of 1 μg/mL of AFPIII (58?±?14%). No significant differences were observed in curvilinear velocity between fresh sperm and cryopreserved sperm with/without addition of AFPI or AFPIII. The flow cytometry analysis revealed that fresh sperm contained 94.5?±?6% live cells, while the cryopreserved sperm only contained 26.6?±?14% live cells. Supplementation of antifreeze proteins has significantly improved the percentage of live cells in frozen-thawed sperm, except 0.1 μg/ml of AFPI group. No significant difference in percentage of live cells was detected in the sperm cryopreserved with 10 μg/mL of AFPI or AFPIII, compared to fresh sperm. Thus, addition of antifreeze proteins to cryopreservation medium could be considered to improve the post-thawed sperm quality of sterlet.  相似文献   
9.
Alzheimer's disease is hypothesized to be caused by an imbalance between β-amyloid (Aβ) production and clearance that leads to Aβ accumulation in the central nervous system (CNS). Aβ production and clearance are key targets in the development of disease-modifying therapeutic agents for Alzheimer's disease. However, there has not been direct evidence of altered Aβ production or clearance in Alzheimer's disease. By using metabolic labeling, we measured Aβ42 and Aβ40 production and clearance rates in the CNS of participants with Alzheimer's disease and cognitively normal controls. Clearance rates for both Aβ42 and Aβ40 were impaired in Alzheimer's disease compared with controls. On average, there were no differences in Aβ40 or Aβ42 production rates. Thus, the common late-onset form of Alzheimer's disease is characterized by an overall impairment in Aβ clearance.  相似文献   
10.
This study investigated the genetic variability within Cylicocyclus nassatus (Nematoda, Strongylida, Cyathostominae) collected from different domestic and wild hosts (i.e. horse, donkey, Przewalskii horse, tarpan and Turkmen kulan) and localities in Europe and/or USA. The ribosomal Internal Transcribed Spacer 2 (ITS2) and the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene were PCR-amplified and sequences characterized from seventy individual parasitic specimens. While ITS2 displayed 0-0.6% variation rate among all individual adult specimens of C. nassatus examined, 22 different sequence variants (haplotypes) of cox1 were detected. Nucleotide variation was detected at 75 of the total 689 positions (overall 10.8% rate of intraspecific nucletidic difference) in the cox1, with the absence of invariable positions among specimens collected from each equid species or country. Conversely, two haplotypes were detected in horses from USA and in donkeys of Italy and Ukraine, respectively. The absence of haplotypes shared by the equid species suggests an affiliation of C. nassatus populations to their specific host. The results of the present study demonstrated that the characterization of mitochondrial regions may have important implications for studying the genetic structure and biology of equine cyathostomes, and to exploit taxonomic issues and practical implications related to the spread of anthelmintic resistance.  相似文献   
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