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The Early Cretaceous lizard genus Dalinghosaurus from the Yixian Formation of Liaoning, China, was originally described on the basis of a partial postcranial skeleton characterised by extremely long slender hind feet and a long tail. The skull has remained unknown and the systematic position is undetermined. Here we describe the skeletal anatomy of this lizard in detail based on a series of new specimens in the collections of the Institute of Vertebrate Paleontology and Paleoanthropology, Beijing. The adult animal is small, with a well−ossified skull having a characteristic pattern of pustulate sculpture on the roofing bones and an expanded angular flange on the lower jaw. Skin impressions show a pattern of fine granular dorsal scales, rhomboidal ventral scales, and elongate tail scales arranged in annulae. In many features, the skull resembles that of the living Xenosaurus and Shinisaurus, as well as Carusia from the Late Cretaceous of Mongolia and China. Phylogenetic analysis using three different data sets provides some support for that interpretation. The postcranial skeleton is characterised by long hind limbs and short forelimbs, but the delicacy of the long pes and the slender claws suggest this animal may have been a climber rather than a facultative bipedal runner.
Species invasion is a significant concern because of its substantial effect on native ecosystems. A number of species-specific invasion predictions that correspond to environmental conditions are available, but literature predicting global species invasion that corresponds to environmental conditions and human activity is scarce. In this study, the potential geographic ranges of 308 alien plant species were predicted under current environmental conditions and human activities. Environmental conditions were delineated by bioclimatic (mean annual temperature, mean annual precipitation, mean temperature of wettest quarter, and precipitation of driest quarter) and topographic variables (annual solar radiation and topographic wetness index). Human activity was delineated by the human footprint, which is a raster data layer created from nine global data layers that describe human population pressure, land use and infrastructure, and human access. The potential distribution of the target species was predicted using the different types of models. By searching the correlated literature, we identified and excluded the native geographic range of the studied species in the predicted geographic range to obtain the exclusive invasive range. Results demonstrated that the invasion hotspots included the southern part of North America, Southern and Western Europe, the south coast of Asia, coastal regions of Australia and New Zealand, the coast of West Africa, the Ivory Coast of Africa, and the southern part of Brazil. In addition, the land areas of the low- (proper for less than 50 alien species), moderate- (51-100 aliens), and high-risk regions (more than 100 aliens) are 213.23, 18.15, and 2.50 million km2, respectively. All variables (bioclimatic and topographic variables and human footprint) were positively correlated with increasing richness of alien species. The highest correlation coefficient was obtained for the human footprint.
The emissions of hazardous trace elements have gained considerable attention because of their negative impacts on local air quality, regional environmental health, and ecological risks. Shandong Province has beenconsidered to be the top provincial emitter of Sb, As, and Se in China owing to rapid economic development and its energy consumption structure (mainly coal). In this study we investigate the atmospheric emissions of Sb, As, and Se from coal combustion in Shandong from 2005 to 2014, and we analyze a scenario for future emissions from coal-fired power plants. The inventory is based on the following parameters: coal consumption, economic sectors, boiler types, and air pollution control technologies. Results indicate that the calculated provincial total emissions of Sb, As, and Se from coal combustion in 2005 were estimated at 40.26, 246.5, and 255.9 t, respectively, and increased to 51.36, 311.9, and 313.9 t by 2014 with annual growth rates of 2.75%, 2.65%, and 2.27%. Industrial use was the largest single sector, accounting for nearly 83.2%, 82.6%, and 74.2% of the provincial total emissions for Sb, As, and Se in 2014, respectively. The emissions from coal-fired power plants have been controlled by the installation of flue gas desulfurization systems. In addition, scenario analysis shows that Sb and As emissions from coal-fired power plants will decrease in the future in a high-efficiency control technology scenario. However, Se emissions in 2030 will still be higher than in 2014. This study demonstrates the importance of assessing the effectiveness of control measures and supplying necessary suggestions for managing coal combustion in Shandong.
With regards to the interchanging features of agricultural pollution and its negative impacts on China’s eco-environment such as environmental degradation, this paper, by fully taking into consideration the gap in environmental technology, incorporated the extended SBM directional distance function and Metaconstraints efficiency function to estimate China’s agricultural environmental efficiency (roughly three regions: eastern, central, and western China), and employed the panel model to study the environmental Kuznets curve’s (EKC) characteristics and the causes of regional differences in agricultural environmental efficiency under levels of different environmental technology. The study showed that, due to the signifi cant differences in agricultural environmental production technology among the three different regions, agricultural environmental efficiency presented a pattern of progressive decline, for instance; eastern China > western China > central China. Although the agricultural environmental technology of eastern China can reach 96.92% of the potential meta-constraint technology level, agricultural environmental technology of central and western China only reach 83.71% and 79.37% of the potential meta-technology constraint, respectively. The EKC curve of agricultural environmental efficiency was proved to be supportive of the circumstances in China; however, as a result of the gap in environmental technology, the EKC curves of different regions presented different turning points and stages. In addition to agricultural economic growth, openness of trade, proportion of agriculture, agricultural technological level, income gap, and fiscal support to agriculture have a significant effect on agricultural environmental efficiency, but both the impact direction and the impact extent of these factors on agricultural environmental efficiency are different.
We studied the effects of roads on presence of Plateau brown frogs (Rana kukunoris Nikolsky, 1918) and Tibetan frogs (Nanorana pleskei Gunther, 1896) in temporary pools of Sedges dominated wetland area in eastern Qinghai- Tibetan Plateau. The road is seven meter-wide, asphalt-paved with daily traffic rate about 400 vehicles. The temporary pools hold water only in summer with surface area of about 2 m2. We used logistic regression models, a theoretic information approach, and model averaging to test the effects of distance from road and depth, area and pH of pools on distribution of frogs in terms of presence/absence in 180 small pools located at 10 to 150 m from the road edge. Observed data showed that presence probabilities of both species declined in the vicinity of roads, starting at approximately 100 m away from the road edge. Model averaging based on AICc (Σωi = 95% confidence) indicated that both distance from road edge and its quadratic term were important predictors for explaining presence of both amphibians. Model-averaged prediction based on 95% confidence model set also revealed non-monotonic increasing curve relationships between presence probability of both amphibians and distance from road edge, even when other habitat variables were held constant. These results indicated that the road-effect zone for both amphibians extended 100 m on side of the wetland roads along which we sampled. Additionally, the results showed that water depth and water pH of pools positively influenced presence of Tibetan frogs and had highest contribution to the models. In contrast, water depth influenced presence of Plateau brown frogs negatively. It was indicated that environmental variables influence the presence of the two species of amphibians in different ways.
Abundant well−preserved salamander fossils have recently been recovered from localities across northeastern China. Pangerpeton sinensis gen. et sp. nov. is represented by a nearly complete skeletal impression of a postmetamorphosed salamander from the Late Jurassic/Early Cretaceous locality of Wubaiding, Liaoning Province. It is characterised by a short wide skull and only 14 presacral vertebrae. Associated soft tissue impressions suggest a warty skin and a broad body outline. Phylogenetic analysis indicates a basal position within Caudata, either just within or just outside crown−group Urodela.
RAPD (randomly amplified polymorphic DNA) and ISSR (intersimple sequence repeat) fingerprinting on HpaII/MspI-digested genomic DNA of nine elite japonica rice cultivars implies inter-cultivar DNA methylation polymorphism. Using both DNA fragments isolated from RAPD or ISSR gels and selected low-copy sequences as probes, methylation-sensitive Southern blot analysis confirms the existence of extensive DNA methylation polymorphism in both genes and DNA repeats among the rice cultivars. The cultivar-specific methylation patterns are stably maintained, and can be used as reliable molecular markers. Transcriptional analysis of four selected sequences (RdRP, AC9, HSP90 and MMR) on leaves and roots from normal and 5-azacytidine-treated seedlings of three representative cultivars shows an association between the transcriptional activity of one of the genes, the mismatch repair (MMR) gene, and its CG methylation patterns.
Neural precursor cells (NPCs), which are capable of self-renewing, migrating to specific sites, and differentiating into the three main CNS lineages, neurons, astrocytes and oligodendrocytes, have been used experimentally to repair the damaged nervous system, either by grafting of cells grown in vitro or by activating endogenous NPCs. The grafting of NPCs, however, is limited by its lower viability and undesired glial differentiation. Understanding the mechanism underlying these events, therefore, is essential for the potential future use of NPCs. In the present study, we investigated the role of histone deacetylase (HDAC) inhibition on survival, proliferation, differentiation and migration of the rat NPCs. We observed that NPCs derived from the E14.5 rat brain constitutively expressed both class I and class II HDAC mRNA. Inhibition of HDAC by trichostatin A (TSA) blocked the proliferation, increased neuronal differentiation and decreased astrocyte differentiation of the NPCs. Meanwhile, TSA had no significant effects on survival and migration of the NPCs. Finally, we found that HDAC inhibition regulated proliferation and neuronal differentiation of the NPCs was associated with a reduction of class II and but not class I HDAC transcription. These findings collectively demonstrate that in the situation of not affecting survival and migration, HDAC inhibition may induce more neuronal differentiation.
The global warming caused by massive energy consumption is one of today’s most serious global environmental problems. CO₂ emissions by the electricity industry in China accounted for 10% of global CO₂ emissions in 2015. This paper studies the impact of different electricity production taxes on China’s energy, economy, and environment. Nine electricity tax scenarios with different tax rates and a dynamic recursive computable general equilibrium (CGE) model were created to analyze this issue. The results show that sectorial output in the coal industry is most sensitive to the tax, and that raising the electricity tax will directly increase the price of electricity. Moreover, increasing the electricity production tax will be helpful for achieving the goal of economic transformation, and to reduce energy consumption as well as CO₂ emissions. The longer the implementation of changing the tax, the lower the cost of emission reduction will be. Therefore, this paper suggests that China can increase the production tax rate of power enterprises moderately in order to reduce energy consumption and adjust the energy structure.
Wastewater recycling technologies have been widely used in tanneries to reduce environmental impacts. However, only a few recycling methods have been developed for vegetable tanning processes due to limited knowledge of their wastewaters. In this study, the structures of the polyphenols in the larch tanning wastewater (LTW) and commercial larch tannin (CLT) were characterized with spectrographic and chromatographic analysis. Structures of these polyphenols were illustrated accordingly; their collagen reaction abilities were then tested with thermal analysis and visualized with a molecular docking software. Results showed that polyphenols in LTW and CLT were all procyanidins. However, average molecular weight of the polyphenols in LTW was 1104Da, in contrast to an obviously higher value for the CLT sample (3334Da). Meanwhile, the LTW presented obvious lower reactivity in the collagen-polyphenol reaction, including lower thermal stabilities and docking energies, fewer hydrogen bonds, and lower interaction energies. These results provide a hint for vegetable tanning wastewater recycling: because of these structural differences, reactivity of the polyphenols in wastewater are lower than the ones in commercial tannins. Therefore, before the recycling processes, polyphenols must be chemically modified in accordance with these structural differences.
This study assessed the performance of recently released 3 arc second SRTM DEM version 4.1 by CSI-CGIAR and 1 arc second ASTER GDEM version 1 and version 2 by METI-NASA in comparison with ground control points from 1:50000 digital line graphs for the coastal zone of Shandong Province, Easter China. The vertical accuracy of SRTM DEM is 13.74 m root mean square error (RMSE), and GDEM version 1 reaches 24.11 m RMSE. Version 2 of ASTER GDEM shows better performance than version 1 and SRTM DEM with a RMSE of 12.12 m. A strong correlation of the magnitude of elevation error with slope and elevation is identified, with lager error magnitudes in the steeper slopes and higher elevations. Taking into account slope and elevation has the potential to considerably improve the accuracy of the SRTM DEM and GDEM version 1 products. However, this improvement for GDEM version 2 can be negligible due to their limited explanatory power for the DEM elevation errors
A PR10 gene (ThPR10) was cloned from Tamarix hispida and characterized. Real-time RT-PCR was employed to evaluate gene expression levels. ThPR10 was expressed in both leaves and roots of T. hispida under normal growth conditions, and can be highly induced in both leaf and root tissues by abiotic stresses including NaCl, PEG, cold, CdCl2, and ABA (abscisic acid) treatments. Our results indicated that ThPR10 is involved in the abiotic stress response, and regulated by an ABA-dependent signaling pathway. Subsequently, ThPR10 was localized at the subcellular level. The gene was fused with the GFP N-terminal driven by CaMV35S promoter and transiently expressed in onion epidermal cells. This strategy localized the ThPR10 protein to the nucleus of onion epidermal cells, suggesting that the pathogenesis-related proteins play a functional role in the cell nucleus.
Gibberellic acid (GA₃) is a plant growth regulator commonly used for increasing the productivity of seedless fruit. However, little is known about the effect of GA₃ on phenolic compounds in grapevine. In the present study, the effect of GA₃ application on contents and antioxidant activities of phenolic compounds in different tissues of Muscat grapevine (Vitis vinifera L. cv. Muscat) was investigated. An application of 100 mg/L GA₃ could successfully induce seedless grape berry, enhance berry size and accelerate the development of berries, resulting in earlier ripening of seedless berry. The contents of total phenolics and total flavonoids, and antioxidant activities in leaf, stem and tendril obviously increased, while these remarkably decreased in berry skin and flesh after GA₃ application. In addition, the grapevine leaf, stem, tendril and skin extracts were shown to contain high amounts of phenolics and significant antioxidant activities. Thus, these findings indicate that GA₃ application causes different effect on phenolic compounds and antioxidant activities, depending on grapevine tissues.
Large scaled projects are conducted in South Yellow Sea in recent years. Topographic effect and tidal current are key issues to the coastal engineering and the ocean engineering. In this study, field surveys were conducted to investigate the tidal level, current velocity, and current direction in South Yellow Sea. A numerical model was developed to simulate the radial current field based on the field data. To investigate the mechanism of the radial current field, the actual topography and a smoothed topography were applied in the numerical model, respectively. Results show that, the current field appeares radial because of the tidal system rather than the submarine topography. Local topography centralized the radiation centre and shifted the high-velocity zones. The actual topographic effect is proposed, and results show that local topography increases the flood tide velocity and decreases the ebb tide velocity. Lagrangian residual currents are calculated to illustrate possible sediment sources and transport routes
Heat stress is one of the most detrimental environment stresses for plants. Hydrogen peroxide (H₂O₂) is produced quickly in response to various stresses and likely plays a positive role in transmitting stress signal in organisms. This investigation addressed whether an exogenous H₂O₂ application would affect the heat response of turfgrasses and induce acclimation. Tall fescue (Festuca arundinacea cv. Barlexas) and perennial ryegrass (Lolium perenne cv. Accent), two important cool-season turfgrasses and forages, were sprayed with 10 mM H₂O₂ before they were treated with heat stress (38/30°C, day/night) and compared with plants maintained at control temperatures (26/15°C, day/night). Prior to the initiation of heat stress, H₂O₂ pretreatment increased the activities of guaiacol peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), glutathione reductase (GR) and glutathionedependent peroxidase (GPX) and the ascorbate and glutathione pool, and it decreased the GSH/GSSG ratio. During the heat stress process, pretreated plants from both grasses exhibited higher turfgrass quality and relative water content, and they experienced lower oxidative damage and H₂O₂ levels. Moreover, the activities of APX, GR, GPX and glutathione-S-transferase increased significantly in response to H₂O₂ pretreatment under heat stress. These results suggested that H₂O₂ most likely participated in the transduction of redox signaling and induced the antioxidative defense system, including various enzymatic and nonenzymatic H₂O₂ scavengers. The scavengers played important roles in improving the thermotolerance of tall fescue and perennial ryegrasses.
Forest soils potentially store a large pool of carbon and phosphorus. A deep understanding of the total carbon and phosphorus stock in forest soils is vital in the assessment of the nutrients dynamics in forest ecosystems. This study examined the effects of elevation, soil depth, and climatic variables, specifically mean annual temperature (MAT) and mean annual precipitation (MAP), on soil carbon and organic phosphorus in Schrenk's spruce (Picea schrenkiana) forest at Tianshan Mountains. Results showed that soil organic carbon (SOC) significantly increased while organic phosphorus decreased with elevation. Interestingly, carbon increased faster with increasing elevation in the alluvial horizon than in the leached horizon, demonstrating the important role of deep soils in carbon sequestration potential. SOC concentration decreased with soil depth, whereas phosphorus concentration initially decreased and then increased. SOC had no significant relationships with MAT and MAP, whereas phosphorus concentration decreased with MAT. Similar to the impacts of MAT and MAP on SOC, these two climatic variables also exerted no significant influence on C:P ratio.
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