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The Rock Sparrow Petronia petronia has been well studied with respect to reproductive biology at low-altitude in Europe, but not at high altitudes. This study presents the information on a Rock Sparrow population breeding in an alpine meadow at 3400 m altitude and compares the life history traits with their lower-altitude counterparts studied in Europe. The birds are resident all year round in this area. Nests of Rock Sparrows tended to cluster and were mainly located in abandoned burrows of the Ground Tit Parus humilis. Pairs were monogamous and territorial behaviors were absent, which differed from European populations, where Rock Sparrows show a series of mating systems and display strong territoriality around the nest site. Egg-laying took place between late May and late June, with every pair making a single nesting attempt. Clutch size averaged 5.1 ± 0.9, incubation undertaken by female only lasted 12.7 ± 0.8 days, and young in the nest were fed by both parents for 19.9 ± 0.7 days. Breeding success, measured as the proportion of nests with at least one fledgling, was 89%. Compared to their lower-altitude populations studied in Europe, the high-altitude Rock Sparrows start breeding later, experience a shorter breeding season, produce fewer but bigger eggs, and have a longer nestling period. Such a life history strategy that allows birds to allocate more energy into individual offspring should be adaptive to the harsh high-altitude conditions.
An increase in the release of sewage discharge and stream ecosystem degradation is contributing to increased chromophoric dissolved organic matter (CDOM) in the Yinma River Watershed, which is a polluted watershed of the Songhua River. This study involves the spatiotemporal characterization of CDOM, CDOM-DOC relationships, and the influence of environmental factors (e.g., natural geographical and anthropogenic activities). Riverine waters showed higher aCDOM (335) and DOC concentrations in the spring and autumn than in the summer, and positive correlations were found between the aCDOM (335) and DOC concentrations in the summer (r = 0.90, 2-tailed, p<0.01) and autumn (r = 0.58, 2-tailed, p<0.01). Storms in May 2016 affected DOC flux from terrestrial ecosystems into the stream, and the CDOM-DOC relationship in the spring. Environmental factors such as water quality, precipitation, soil, gradient, land-use, and GDP could have affected the optical properties of CDOM (DOC). Gradient was correlated with the optical properties (2-tailed, p<0.05) of CDOM. Types of land-use, pollutant discharge from point sources, and GDP (r = 0.58, 2-tailed, p<0.05) affected the composition and creation of CDOM (DOC). The correlations among CDOM absorption parameters, gradient, and GDP were driven by samples that were related to regional terrestrial and anthropogenic pollutants. High loading of complex CDOM (DOC) inputs from anthropogenic activities combine with natural influences and constitute a challenge for CDOM (DOC)-derived pollution treatment, and treatment of pollution in the watershed.
Eleven new species of the family Mysmenidae occurring in China, in addition to one known species, Mysmenella gongi Yin, Peng et Bao, 2004, that was reported from Hunan Province, are diagnosed, described and illustrated. Three genera, i.e., Calodipoena, Mysmena, and Trogloneta, are firstly reported in China. Mysmenella pseudojobi sp. nov., where is found hitherto at the northest range of distribution of the family in China, and Trogloneta denticocleari sp. nov. is collected in caves. Mysmena spirala sp. nov. is collected from rainforest in Hainan Province. Calodipoena biangulata sp. nov., C. cornigera sp. nov., Mysmena zhengi sp. nov., M. rostella sp. nov., M. furca sp. nov., M. arcilongus sp. nov., Mysmenella menglunensis sp. nov. and Trogloneta speciosum sp. nov., from Xishuangbanna in Yunnan Province, are collected by fogging. Natural history and distributional map are provided.
Four new species of oonopid spiders are described from southwest China. Two of these are placed in the new genus Trilacuna gen. nov.: T. angularis sp. nov. and T. rastrum sp. nov. (type species). Trilacuna gen. nov. is characterized by the enlarged male palpal femur, the complicated embolus-conductor complex, the branched male endites and the notched labium. A further two species are Camptoscaphiella tuberans sp. nov. and Gamasomorpha barbifera sp. nov. A key to 10 genera and 23 species of the currently known Chinese oonopid spiders is given.
Cave Draconarius spiders in China were rarely reported. In the present paper, seven new Draconarius species collected from caves in China are described and illustrated. They are D. auriformis sp. nov., D. brachialis sp. nov., D. tongi sp. nov., D. ovillus sp. nov., D. specialis sp. nov., D. spirallus sp. nov. and D. tubercularis sp. nov. Distribution maps of Draconarius spiders are provided.
Celem pracy było określenie wpływu różnych metod suszenia i temperatury procesu na aktywność przeciwutleniającą ekstraktów otrzymanych z suszonych jabłek. Najwyższą zdolnością neutralizacji wolnych rodników charakteryzował się ekstrakt z suszu sublimacyjnego. Stwierdzono statystycznie istotną, mniejszą jego aktywność przeciwutleniającą w stosunku do surowego jabłka (zmniejszenie aktywności wyniosło około 9%) jedynie w przypadku zastosowania temperatury półki wynoszącej 40°C. Jednocześnie, mimo nieznacznego zmniejszenia, zawartość polifenoli w tych suszach nie różniła się istotnie od ich zawartości w surowcu przed suszeniem. Podczas suszenia konwekcyjnego aktywność przeciwutleniająca jabłek zmniejszyła się znacząco, osiągając 60-80% aktywności surowca przed suszeniem. Podobnie zawartość polifenoli uległa około 30- 35-procentowej redukcji. Suszenie niskotemperaturowe również spowodowało zmniejszenie aktywności przeciwutleniającej i zawartości polifenoli, jednak nie było ono tak istotne, jak w przypadku suszenia w wysokiej temperaturze, ale większe niż suszu sublimacyjnego. Aktywność przeciwutleniająca zmniejszyła się o około 8-27%, zaś zawartość polifenoli - w granicach 5-29%. Nie stwierdzono jednoznacznego wpływu poziomu temperatury na badane wskaźniki jakości suszu, niezależnie od zastosowanej metody suszenia.
Genetic mechanism underlying peach flower color variegation has been intensively investigated at transcriptome level, but an elucidation at proteome level is still scarce. In this study, we performed proteome analysis with a peach cultivar bearing white and red flowers simultaneously on the same tree, and identified the differentially expressed proteins (DEPs) in the red and white flowers at different development stages. A total of 149 DEPs were identified. Among which, 99 were from peach flower buds, and 50 were from expanded but unflushed flowers. It is noteworthy that about 70% of the DEPs are upregulated in red flowers, and the enriched pathways in red flowers at protein level mainly include starch and sucrose metabolism, carbon fixation, and glycolysis (AMY1, UGP, PGK3, TPI, PPA, ATP5H, and RuBisCO), which provide more substrate and energy for anthocyanin biosynthesis. In addition, a number of RNA-binding proteins (RBPs) and proteasome which play key roles in the regulation of gene expression at levels of transcription, splicing and mRNA stability are also found to upregulate in red flowers. Among them, eight glycine-rich RBPs (spot A26, A34, A54, A71, A72, A74, B24, and B42) and a branch point-bridging protein (spot B4) are identified as important proteins involving in alternative splicing of mRNA. As a result of alternative splicing, anthocyanidin synthase (ANS) activity is found to express dramatically higher in red flowers. Besides, a GST protein (XP_007200490.2) involving in anthocyanin transportation is found to significantly upregulate in red flower buds. Unlike the previous reports based on transcriptome analysis, no proteins coded by structural genes in anthocyanin biosynthesis were found obviously upregulated in red flowers in this study. Our findings indicated that flower color variegation should be regulated at both transcriptional and post-transcriptional levels, and genes involved in transcripts alternative splicing and anthocyanin transportation were essential for flower color variegation in peach.
Potato is one of the most important food crops in the world. Many plant transcription factors (TFs) have been demonstrated to be essential for improvement of plant stress tolerance traits. However, very few TFs were used for improving potato stress tolerance. In this study, we presented the characterization of a new potato StNAC2 gene. The StNAC2 protein contains five subdomains of NAC proteins and belongs to NAP subfamily. StNAC2 is constitutively expressed in potato leaves, stems, tubers, flowers and roots. Transcripts of StNAC2 were significantly induced by Phytophthora infestans, the causal agent pathogen of potato late blight. StNAC2 also could be induced by wounding, salt, drought as well as signal molecules such as salicylic acid and abscisic acid, suggesting that StNAC2 transcription factor involved in the signal transduction cascades in responses to abiotic and biotic stresses in potato. Overexpression of StNAC2 in transgenic potato significantly enhanced salt tolerance in vitro and drought tolerance in pot growing condition. Thus, the functional analysis of the new StNAC2 gene in this study will enrich knowledge for understanding the function of the NAC genes in potato stress tolerance.
The passenger domain gene of PmpD of swine Chlamydophila abortus CP 16 was amplified, subcloned into the pet-32a(+) vector, then sequenced, and expressed in Escherichia coli BL21(DE3). The target protein was identified by Western blotting. It was demonstrated by sequence analysis that the passenger domain gene of Pomp18 contained 1317 bp that encoded a protein of 439 amino acids. The homology of the target gene was found to be 97.0%, 97.0%, 97.2% , 52.6%, 44.6%, and 87.5%, respectively, identical to that of the CPD13, S26/3, 1B, TW-183, TW-396, and CAL-10 strains of C. abortus. The recombinant 65.3 kDa protein was identified by both SDS-PAGE and Western blotting. A positive reaction was observed with swine positive serum, while neither sheep serum nor avian serum reacted with the target protein. In conclusion, the passenger domain of PmpD gene was at first cloned and expressed successfully. The recombinant protein showed the species reaction and might play a major role in C. abortus infection.
In this work, porous HAP nanofibers assembled from nanorods were developed as potential devices for the treatment of Cu(II), Cd(II), and Pb(II) contamination of consumable waters. Two steps were employed in the HAP nanofibers fabrication. First, rod-like HAP nanoparticles were synthesized through a chemical pathway from Ca(NO₃)₂ ·4H₂O, (NH₄)₂ HPO₄, and polyvinylpyrrolidone (PVP) as a capping agent. The subsequent electrospinning was performed to fabricate the PVP/HAP hybrid nanofibers as precursors to obtain pure HAP nanofibers assembled from nanorods via a calcination process. The effects of PVP dosage on morphology was investigated. And a possible formation mechanism of rod-like HAP was proposed. Then the removal efficiency of porous HAP nanofibers toward Cu(II), Cd(II), and Pb(II) were evaluated via sorption kinetics and sorption isotherms. Our results proved that the sorption kinetic data were well fitted by the pseudo second-order rate equation, and the adsorption of Cu²⁺, Cd², and Pb²⁺ ions on HAP nanofibers correlated well with the Langmuir equation as compared to Freundlich isotherm equation under the concentration range studied. These novel porous HAP nanofibers assembled from nanorods promise a feasible advance in the development of new, easy to handle, and low-cost water purifying methods.
Grassland degradation due to anthropogenic and natural factors and their interactions is one of the worldwide ecological and economic problems because it reduces grassland productivity and diversity and leads to desertification. The objective of this study was to assess the influence of protective enclosure on vegetation composition and diversity and plant biomass of an alpine degraded meadow. The experiment was conducted at center of Qinghai-Tibetan Plateau with two degraded (caused by overgrazing) alpine meadows: the lightly and severely degraded ones (LD and SD) and their enclosed areas with iron net (LDE and SDE, respectively). The areas 200 m × 150 m for each of four degraded alpine meadow treatments at average altitude 3,960 m a.s.l. were set for research. The lightly degraded plots were dominated by Scirpus distigmaticus (Kukenth.) Tang et Wang, Elymus nutans Griseb. and Oxytropis ochrocephala Bunge. The dominating plants in severely degraded plots were: Artemisia sieversiana Ehrhart ex Willd, Ajania tenuifolia (Jacq.) Tzvel, Lonicera minuta Batal. The results showed: (1) the vegetation cover of two degraded plots (LD and SD) has increased after taking the enclosure measures and the forbs dominated both plots. (2) Species richness has also increased in two enclosed degraded plots, respectively. There no significant differences in evenness and diversity between LD and LDE, and SD and SDE, respectively. (3) Enclosure may promote aboveground biomass, particularly grass and forb biomass in LD, and forb biomass in SD plots.
This paper evaluates the feasibility and stability of the construction of a super-large-scale filtered tailings storage facility on coal-mining subsidence land. Properties of the coal gangue were analyzed by laboratory tests and change laws of the land subsidence were observed in the field. Comparisons of slope stability between the super large-scale filtered tailings storage facility and conventional tailings impoundment in normal, flooded, sustained rainfall, and strong earthquake conditions were conducted using Slide software. The results show that the filtered tailings storage facility has less chance of failure, lower seepage probability, and smaller impact scope than conventional tailings impoundment. With little free water in filtered tailings, the average slope safety factors of filtered tailings storage are as high as 1.78 in normal, 1.73 in flood, 1.18 in sustained rainfall, and 1.11 in a magnitude-8.0 earthquake. As an environmentally friendly, cost-effective chain-cutting disaster mitigation measure, filtered tailings disposal shows great advantages in reducing tailing emissions, dam construction scale, and operational costs, improving water conservation, dam stability, and service life.
The variations in leaf traits of Taxus species in different light conditions are still poorly understood. We sampled leaves of Taxus yunnanensis W. C. Chang L. K. Fu and Taxus chinensis var. mairei (Lemée and Lév.) W. C. Cheng and L. K. Fu along an illumination gradient (full daylight, 40–60% full daylight, <10% full daylight), and analyzed how seven leaf traits and their correlations changed under different light conditions. The leaf trait that showed the greatest variation was specific leaf area (SLA) for T. yunnanensis, followed by leaf dry mass (LM) for both taxa. The smallest variation was in leaf width (LW) for both taxa. Plasticities of all leaf traits in both taxa were higher than 50%, and those of leaf area (LA), LM and SLA were greater than 80%. The light gradient was positively correlated with leaf length (LL), LM, leaf dry matter content (LDMC), and leaf length to width ratio (LWR). LW and SLA were negatively correlated with the light gradient. Analyses of relationships among leaf traits showed that LM of T. yunnanensis, T. chinensis var. mairei and both taxa was positively correlated with LL, LW, LA, LDMC, and LWR, and negatively correlated with SLA under all light conditions. We concluded that leaf traits and their relationships were affected by light conditions.
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