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31.
Leaves of durum wheat infested with mines of the cereal leaf miner Syringopais temperatella Lederer (Lepidoptera: Scythridae) were collected from fields in Israel in spring 2016 and 2017. The parasitoids and moths reared from the leaf mines in the lab were identified and counted according to sex. The sex ratios of S. temperatella were 1:0.73 (♀ :♂) in 2016 and 1:0.41 in 2017. A cross-correlation analysis revealed that males appeared three days ahead of females (p<0.05). The following parasitoids were reared: Eulophidae (Cirrospilus vittatus Walker, Diglyphus chabrias (Walker), D. isaea (Walker), D. sensilis Yefremova, D. pusztensis (Erd?s & Novicky), Necremnus tidius (Walker), Neochrysocharis formosus (Westwood), Pnigalio gyamiensis Myartseva & Kurashev, P. pectinicornis Linnaeus), Pteromalidae (Norbanus sp.) and Braconidae (Habrobracon stabilis (Wesmail), Apanteles sp.); and Icheumonidae (Campoplex sp.). In all cases, the parasitoids emerged substantially prior to the mass appearance of the moths. The hatching dynamics of ecto- and endoparasitoids were also asynchronous. Most species of ectoparasitoids hatched three days ahead of the endoparasitoids (p<0.05). Syringopais temperatella recorded on clover revealed a similar dynamics of male appearance ahead of female, with a of female-to-male ratio of 1:0.25, and fewer parasitoid species. 相似文献
32.
Nikolay A. SHCHIPANOV Artem V. ARTAMONOV Sergey V. TITOV Svetlana V. PAVLOVA 《Integrative zoology》2023,18(3):469-492
The spatial genetic structure is a topical issue in the studies of various aspects of ecology and evolution. Using the multilocus autocorrelation method with hypervariable microsatellite genetic markers, we investigated a fine-scale pattern of genetic structure in 5 local populations of the common shrew Sorex araneus separated by distances of 300–1000 m (the Moscow chromosomal race). Spatial genetic autocorrelation analysis based on 5 microsatellite loci (expected heterozygosity >0.79) with 90 alleles revealed a consistent pattern of significant positive genetic structure. By testing the autocorrelation at multiple scales from 25 to 500 m, we found that positive spatial genetic structure is detectable in distance classes of <500 m. The weaker spatial genetic structure positively correlated with a higher ratio of nonresident individuals to residents’ activity (number of captures). In contrast to nonresident animals, the residents demonstrated prominent genetic structure. Genetic difference (FST) between the populations was significant (0.016–0.051) and comparable with that between populations of different races analyzed previously (0.016–0.038). FST was not associated with geographic distance. These demographic patterns allowed us to propose a scheme of genetic-structure dynamics involving periodic appearance of more related local groups and renewal of allelic profiles from а common pool where the alleles are mixed. The scheme predicts fluctuating genetic structure and random similar differences among local populations. 相似文献
33.
Goranov NV 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2007,36(2):192-195
BACKGROUND:Chondrocyte lipid peroxidation is strongly suggested to mediate collagen degradation and thus, to be involved in the pathogenesis of cartilage degradation and osteoarthritis (OA). OBJECTIVES: The objective of this study was to evaluate early changes in serum biochemical indicators of oxidative stress during the development of OA in a canine model. METHODS: Experimental OA was induced in 7 dogs by transection of the anterior cruciate ligament (Pond-Nuki model). Venous blood samples were obtained prior to the operation and on postoperative days 30, 60, and 105. The activity of serum catalase (an antioxidant enzyme), malondialdehyde (MDA) concentration (a marker of lipid peroxidation), and serum C2C neoepitope concentration (a marker of collagen type II degradation) were measured. RESULTS: A statistically significant increase in all parameters as early as the 30th postoperative day was observed, compared with preoperative values. Serum catalase activity peaked on day 60, whereas MDA and C2C concentrations increased continuously until the end of the experimental period. A significant positive correlation was found between MDA and C2C concentrations, but not between catalase activity and MDA or C2C concentrations. CONCLUSIONS: The results support the hypothesis that oxidative stress is involved in the pathogenesis of OA in the dog based on the Pond-Nuki model. The correlation between MDA and C2C concentrations suggests a possible association between oxidative stress and cartilage degeneration. 相似文献
34.
Anna Gebruk Polina Mikhaylyukova Maria Mardashova Varvara Semenova Lea-Anne Henry Nikolay Shabalin Bhavani E. Narayanaswamy Vadim Mokievsky 《水产资源保护:海洋与淡水生态系统》2021,31(1):112-125
- The Atlantic walrus, Odobenus rosmarus rosmarus, forms a herd of nearly 4,000 heads in the Pechora Sea (south-eastern Barents Sea). The Near Threatened status of O. rosmarus rosmarus and the relative isolation of the Pechora Sea population, as well as the potential impacts of human activities in the area, make it important to characterize key habitats, including feeding grounds, in order to protect the species.
- The aim of the present study was to integrate multiple sources of environmental and biological data collected by satellite telemetry, remotely operated vehicle (ROV), and benthic grab sampling to examine the distribution and diversity of benthic foraging resources used by walrus in the Pechora Sea.
- Analysis of satellite telemetry data from seven males tagged on Vaigach Island helped to identify areas of high use by walruses near haulout sites on Matveev and Vaigach islands, and in between. Field data were collected from those feeding grounds in July 2016 using ROV video recordings and bottom grab sampling. Analysis of 19 grab stations revealed a heterogeneous macrobenthic community of 133 taxa with a mean biomass of 147.11 ± 7.35 g/m2. Bivalve molluscs, particularly Astarte borealis, Astarte montagui, and Ciliatocardium ciliatum, dominated the overall macrobenthic biomass, making up two-thirds of the total.
- Analysis of 16 ROV video transects showed high occurrences of mobile benthic decapods (3.03 ± 2.74 ind./min) and provided the first direct evidence that areas actively used by walrus in the Pechora Sea overlap with the distribution of the non-native omnivorous snow crab, Chionoecetes opilio.
- Integrating multiple data sources provides an early foundation for the kinds of ecosystem-based approaches needed to improve Pechora Sea resource management and to underpin Russia’s nascent marine spatial planning initiatives. Factors that need to be considered in marine spatial planning include impacts on benthic feeding grounds from offshore oil and gas development and the spread of the snow crab.
35.
Katona G Carpentier P Nivière V Amara P Adam V Ohana J Tsanov N Bourgeois D 《Science (New York, N.Y.)》2007,316(5823):449-453
Iron-peroxide intermediates are central in the reaction cycle of many iron-containing biomolecules. We trapped iron(III)-(hydro)peroxo species in crystals of superoxide reductase (SOR), a nonheme mononuclear iron enzyme that scavenges superoxide radicals. X-ray diffraction data at 1.95 angstrom resolution and Raman spectra recorded in crystallo revealed iron-(hydro)peroxo intermediates with the (hydro)peroxo group bound end-on. The dynamic SOR active site promotes the formation of transient hydrogen bond networks, which presumably assist the cleavage of the iron-oxygen bond in order to release the reaction product, hydrogen peroxide. 相似文献
36.
Stephens BB Gurney KR Tans PP Sweeney C Peters W Bruhwiler L Ciais P Ramonet M Bousquet P Nakazawa T Aoki S Machida T Inoue G Vinnichenko N Lloyd J Jordan A Heimann M Shibistova O Langenfelds RL Steele LP Francey RJ Denning AS 《Science (New York, N.Y.)》2007,316(5832):1732-1735
Measurements of midday vertical atmospheric CO2 distributions reveal annual-mean vertical CO2 gradients that are inconsistent with atmospheric models that estimate a large transfer of terrestrial carbon from tropical to northern latitudes. The three models that most closely reproduce the observed annual-mean vertical CO2 gradients estimate weaker northern uptake of -1.5 petagrams of carbon per year (Pg C year(-1)) and weaker tropical emission of +0.1 Pg C year(-1) compared with previous consensus estimates of -2.4 and +1.8 Pg C year(-1), respectively. This suggests that northern terrestrial uptake of industrial CO2 emissions plays a smaller role than previously thought and that, after subtracting land-use emissions, tropical ecosystems may currently be strong sinks for CO2. 相似文献
37.
Svetlana N. Sushkova Tatiana M. Minkina Saglara S. Mandzhieva Galina K. Vasilyeva Nikolay I. Borisenko Irina G. Turina Olga V. Bolotova Tatiana V. Varduni Rıdvan Kızılkaya 《Journal of Soils and Sediments》2016,16(4):1323-1329
Purpose
The optimization of benzo[a]pyrene extraction conditions by subcritical water extraction method from soils is the purpose of the research. The optimal conditions for benzo[a]pyrene recovery are 30-min extraction by water in a special steel cartridge at 250 °C and 100 atm.Materials and methods
Studies were conducted on the soils of monitoring plots subjected to Novocherkassk Power Station emissions. Monitoring plots were established at different distances from the Novocherkassk Power Station (NPS; 1.0–20.0 km).Results and discussion
It was shown that the use of water in subcritical state as a solvent for benzo[a]pyrene extraction from soil allows to avoid large volumes of organic solvents and to decrease the time of sample preparation. It is shown that the maximum benzo[a]pyrene maintenance was observed in soils of the monitoring plots located most close (to 5 km) to a pollution source in the area of the prevailing direction of a wind rose. Dynamics of pollutant accumulation in soils depend on number of Novocherkassk state district power station emissions.Conclusions
The method of benzo[a]pyrene subcritical water extraction from soil was developed and approbated during long-term monitoring researches of technogenic polluted territories. The optimum conditions for benzo[a]pyrene extraction from soil have been determined: the soil is treating by subcritical water at 250 °C and 100 atm of pressure for 30 min. Trends in the accumulation of benzo[a]pyrene in soil zones of the thermal power plant influence have been researched over a 5-year period of monitoring observations by subcritical water extraction method. Benzo[a]pyrene accumulation in soils depends on the technogenic emissions to the atmosphere from Novocherkassk power station and on the soil physical and chemical properties.38.
39.
Igor Jerkovi Ana-Marija Ciko Sanja Babi Lara imek Krunoslav Bojani Krunoslav Aladi Nikolay V. Ulyanovskii Dmitry S. Kosyakov Albert T. Lebedev Rozelindra o-Rakovac Polonca Trebe Stela Joki 《Marine drugs》2021,19(5)
The endemic brown macroalga Fucus virsoides J. Agardh from the Adriatic Sea was in the focus of the present research. The volatiles of fresh (FrFv) and air-dried (DrFv) samples of F. virsoides obtained by headspace solid-phase microextraction (HS-SPME) and hydrodistillation (HD) were analyzed by gas chromatography equipped with flame ionization detector and mass spectrometry (GC-FID/MS). The major HS-FrFv compound was pentadecane (61.90–71.55%) followed by pentadec-1-ene (11.00–7.98%). In HS-DrFv, pentadec-1-ene was not present, and few lower aliphatic compounds appeared, as well as benzaldehyde and benzyl alcohol. In HD-FrFv, particularly abundant were alkenes (such as pentadec-1-ene (19.32%), or (E)-pentadec-7-ene (8.35%)). In HD-DrFv, more oxidation products were present (e.g., carbonyl compounds such as tridecanal (18.51%)). The fatty acids profile of freeze-dried sample (FdFv) after conversion to methyl esters was determined by GC-FID, and oleic acid was dominant (42.28%), followed by arachidonic acid (15.00%). High-performance liquid chromatography-high-resolution mass spectrometry with electrospray ionization (HPLC-ESI-HRMS) was used for the screening of less polar fractions (F3 and F4) of F. virsoides. Mono- and diglycerides of stearic, palmitic, oleic, and arachidonic acids were found. Terpenoids and steroids comprised the compounds C20H30(32)O2 and C29H48O(2). Among carotenoids, fucoxanthin was identified. Chlorophyll derivatives were also found (C55H74(72)N4O(5-7)), dominated by pheophytin a. The antioxidant activity of the fractions was investigated by in vitro assays (oxygen radical absorbance capacity (ORAC), reduction of radical cation (ABTS•+), 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) assay, and ferric reducing antioxidant power (FRAP)) and by in vivo zebrafish model (along with fish embryotoxicity). In vitro experiments proved good radical scavenging abilities of F3 and F4 fractions, which were additionally supported by the protective effect against hydrogen peroxide-induced oxidative stress in zebrafish embryos. 相似文献
40.
Aleksandr KAVETSKIY Galina YAKUBOVA Nikolay SARGSYAN Clyde WIKLE Stephen A. PRIOR Henry Allen TORBERT Bryan A. CHIN 《土壤圈》2019,29(3):334-343
Soil carbon mapping is extremely useful in assessing the effect of land management practices on soil carbon storage. Applications of neutron-gamma analysis in scanning mode for mapping of soil carbon are discussed. A Global Positioning System(GPS) device and softwares required to simultaneously acquire gamma signals and geographical positions during scanning operations were added to an existing measurement system. The reliability of soil carbon measurements in scanning mode was demonstrated to be in agreement with results acquired from static mode. The error analysis indicated that scanning measurements can be conducted with the same accuracy as static measurements in approximately one fourth the time. To obtain results suitable for mapping analogous to traditional chemical analyses(i.e., ± 0.5 in weight percent or ± 0.5 w%), scanning time over a given site should be ca. 15 min using the current measurement system configuration. Based on this measurement time, a reasonable towing speed of 3–5 km h-1, the necessity for complete site coverage during scanning, the number of sites(within the surveyed field), and the required total measurement time can be estimated. Soil carbon measurements for 28 field sites(total area ca. 2.5 ha) were conducted in ca. 8 h. Based on acquired data,a soil carbon distribution map was constructed utilizing various softwares. The surveyed field area included an asphalt road that had carbon readings higher than the surrounding land. The clarity with which these carbon-rich zones were delineated on the constructed map represents evidence supporting the veracity of this method. Neutron-gamma analysis technology can greatly facilitate timely construction of soil carbon maps. 相似文献