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A cubic crystal form Co₃O₄ was synthesized using the sol-gel method and applied as catalyst in the visible light-driven photocatalytic degradation of 1,2,4-trichlorobenzene (1,2,,4-TCB). 1,2,4-TCB removal efficiency initially increased and was followed by a gentle decrease as the Co₃O₄ dosage increased, with the optimal dosage of 2.0 g/L. The degradation rate changed positively with light intensity and reaction temperature. However, pH exerted only a slight effect on 1,2,4-TCB degradation. Strong acidic and basic conditions were conducive to the photocatalytic degradation of 1,2,4-TCB. The optimal parameters for the photocatalytic degradation of 1,2,4-TCB were found at a Co₃O4 dosage of 2.0 g/L, 350 W of illumination intensity, initial 1,2,4-TCB concentration of 7.5 mg/L at 30ºC, with 1,2,4-TCB removal efficiency of 90.13% after 6.0 hours photocatalytic degradation. The Co₃O₄ synthesized in the study with high-purity and stable properties guaranteed its high catalytic activity and stability. The possible mechanisms of visible light-driven photocatalytic degradation of 1,2,4-TCB with synthesized Co₃O₄ photocatalyst were also proposed.
Linkage and association studies suggested the relationship between α-adducin polymorphism (Gly460Trp; rs4961) and genetic susceptibility to salt-sensitivity. However, the currently available results were inconsistent. This study aimed to define quantitatively the association between salt-sensitivity and α-adducin Gly460Trp polymorphism in all published case-control studies. Publications from PubMed and other databases were retrieved. The major inclusion criteria were: (1) case-control design; (2) salt-sensitivity confirmed by sodium loading tests, and (3) the distribution of genotypes given in detail. Seven case-control studies fulfilled the inclusion criteria. In total they involved 820 subjects (454 salt-sensitive and 366 non-salt-sensitive). The meta-analysis shows that Gly460Trp polymorphism in general is not significantly associated with salt-sensitivity [OR (95%CI): 1.40 (0.96,2.04), P = 0.08]. Subgroup analysis showed that the association is statistically significant in Asian people [OR (95%CI): 1.33 (1.06, 1.69), P = 0.02] but not in Caucasian people [OR (95%CI): 1.98 (0.57, 6.92), P = 0.28]. This indicates that blood pressure response to sodium varies between ethnical groups. More studies based on a larger population are required to evaluate further the role of α-adducin Gly460Trp polymorphism in salt-sensitive hypertension.
The morphological features of plants, such as leaf functional traits, are adaptations that enable them to live under different environmental conditions. Thus, leaf functional traits can provide a link between various environmental factors and leaf functions. This study aims to gain insights into the differences in leaf functional traits between healthy (no insect attack) and damaged (serious insect attack) Cerasus yedoensis Yü li. Petiole diameter, leaf length, leaf thickness, ratio of leaf length to petiole length, leaf shape index, and single leaf wet and dry weight of damaged leaves were significantly higher than those of healthy leaves, but lower for leaf moisture and specific leaf area (SLA). Plasticity indices of petiole diameter, petiole length, leaf length, leaf width, and leaf shape index of healthy leaves were higher than those of damaged leaes, but contrary for the plasticity indices of the ratio of leaf length to petiole length, leaf moisture, and SLA of healthy leaves. SLA was positively correlated with leaf moisture but negatively correlated with petiole diameter, leaf length, leaf thickness, ratio of leaf legth to petiole length, leaf shape index, and single leaf wet and dry weight. After serious insect attack, damaged C. yedoensis contained increased quantities of material investment per unit area to exhibit a more efficient anti-herbivore defense; thus, leaf moisture and SLA were decreased, but leaf thickness, and single leaf wet and dry weight were increased. Meanwhile, damaged leaves also were more slender and invested more biomass to the lamina than to the petiole.
Resource endowment and resource carrying capacity (RCC) are the most important cornerstones of regional sustainable development. By applying a newly established RCC method, namely, the relative resources carrying capacity (RRCC) method, we evaluated the RCC in the Tarim River basin (TRB) in arid China in Xinjiang during 2000-2011. Research results show that the relative resources carrying capacity can be effectively served as indicators of regional resources sustainable development status. Taking Xinjiang as the reference region, the TRB can be characterized as an area with an overloaded population and surplus economy during the whole research period, where land resources are relative advantage resources carrying the regional population growth and economic development and water resources are relative disadvantage resources restricting rapid regional development. Taking TRB as the reference region, 42 counties and cities in TRB performed significant temporal and spatial disparities according to the RRCC based on population and economic perspectives. Based on the spatial-temporal evolution of RRCC, 42 counties and cities in TRB were classified into four matching modes (A, B, C, and D). The spatial-temporal evolution characteristics and mechanisms about the 42 prefectures and cities were examined, and the suitable development strategies for every different mode were recommended.
Controlling carbon emissions without impairing urbanization and economic development highlights the necessity of researching energy-related carbon emissions. Urban areas have become the main source of energy consumption and carbon emissions. This paper has developed a modified version of the Kaya identity, which incorporates urbanization and resident consumption, to analyze urbanization effect on carbon emissions in Jiangsu Province. Then, the Kuznets curve theory was introduced to estimate the inflection point of the marginal urbanization effect. The results indicated that the urbanization effect was still an important factor that influences total carbon emissions. The marginal urbanization effect will still increase until the urbanization rate reaches 78.94%. Therefore, Jiangsu should also pay attention to the urbanization effect even though it may increase slowly or decrease, and the results of this paper on marginal urbanization effect make it clear that controlling the carbon emissions without the expense of urbanization growth and economic development is still a big challenge for Jiangsu Province. We have proposed some policy recommendations, which include paying attention to the quality of development of urbanization, adjusting the industrial structure, making changes to lifestyles, and so on.
In the present study, the Eastern Star ferry accident was analyzed via 24Model. 24Model, as an accident causation model based on system thinking, holds that all causations of the accident are hazards and all hazards in the system need to be identified and comprehensively controlled in accident prevention. The result showed that five factors were the main causes of the accident. First, the direct causes: bad weather, the bad condition of the hull and the unsafe acts of the captain. Second, the indirect cause: the lack of safety awareness and safety knowledge of both the captain and the company’s senior management. Third, there were loopholes in safety management system, including the training, supervision and execution of the company. Forth, the root cause: the company didn’t establish a good safety culture. Last, the external causes: the severe market pressure, excessive regulatory authorities with puzzled relations and responsibilities—seriously hindered effective supervision. In order to prevent this kind of accident and to secure shipping system, the shipping companies and the relevant regulatory units should draw lessons from the five factors mentioned above, and take measures to identify and control those hazards
Structure characteristics of rock and orebody in deep borehole are obtained by borehole camera technology. By investigating on the joints and fissures in Shapinggou molybdenum mine, the dominant orientation of joint fissure in surrounding rock and orebody were statistically analyzed. Applying the theory of metallogeny and geostatistics, the relationship between joint fissure and lode’s extension direction is explored. The results indicate that joints in the orebody of ZK61borehole have only one dominant orientation SE126° <68°, however, the dominant orientations of joints in surrounding rock were SE118° <73°, SW225°<70° and SE122° <65°, NE79° <63°. Then a preliminary conclusion showed that the lode’s extension direction is specific and it is influenced by joints of surrounding rock. Results of other boreholes are generally agree well with the ZK61, suggesting the analysis reliably reflects the lode’s extension properties and the conclusion presents important references for deep ore prospecting
In this paper, a comprehensive research of the evolution of the hierarchical structure and spatial pattern of coastal cities in China was conducted based on the data of distribution of the headquarters and subsidiaries of marine-related enterprises in 1995, 2005 and 2015 using the city network research method proposed by Taylor. The results of the empirical research showed: China’s coastal city network had an obvious hierarchical characteristics of “national coastal cityregional coastal city-sub-regional coastal city-local coastal city”, in the 20 years of development process, the hierarchies of coastal cities in China showed a hierarchical progressive evolution; in past 20 years, the spatial pattern and network structure of coastal cities in China tended to be complete, and the city network was more uniform, forming a “three tiers and three urban agglomerations” network structure; the strength of connection among the cities was obviously strengthened, and the efficiency of urban spatial connection was improved overall
The concentrations of different phosphorus (P) species and four kinds of bioavailable P (algae-available P, AAP; Olsen P, OLP; water-soluble P, WSP; and readily desorbable P, RDP) were determined to investigate the relationship between phosphorus bioavailability and phosphorus speciation in sediments from rural rivers in Taihu Lake area, China, using a European Commission “Standards Measurements and Testing Program” protocol and four chemical extraction techniques. The total P and inorganic P concentrations in the sediments were 179-2,293 mg/kg and 137-1,857 mg/kg, respectively. The concentrations of the P species in the sediments followed the order NaOH- extractable P > HCl-extractable P > organic P. The bioavailable P concentrations followed the order AAP (340 mg/kg) > OLP (38.7 mg/kg) > WSP (1.8 mg/kg) > RDP (0.3 mg/kg). Regression analyses showed that there were good correlations between the P species concentrations and the bioavailable P concentrations measured using the four different methods, except for between WSP and the HCl-extractable P concentrations. The OLP concentrations had highly significant correlations with AAP, WSP, RDP and the P species concentrations. The OLP method was found to be most suitable for determining the bioavailability of P species under the prevalent geochemical conditions in the rural river sediments that were analyzed.
This study aims to gain insights into the allelopathic effects (by using leaf extracts) of the notorious invasive Solidago canadensis L. on seed germination of the associated Pterocypsela laciniata (Houtt.) C. Shih under different nitrogen (N) forms added: inorganic (NO3--N and NH4 -N), organic (urea-N), and mixed N (a mixture of the three N forms at 1:1:1 ratio). Among the two used concentrations of S. canadensis leaf extracts the higher exhibited inhibitory allelopathic effects on seedling height and biomass, germination potential, germination index, and vigor index of P. laciniata. N demonstrated positive effects on seed germination of P. laciniata. The effects of mixed and organic N on the seedling biomass of P. laciniata were more pronounced than those of inorganic N and control treatment. The vigor index of P. laciniata under mixed N was significantly higher than those under single N form and control treatment. Thus, organic and mixed N showed higher ecological effects on seed germination of P. laciniata than inorganic and single N form. All N forms could alleviate the inhibitory allelopathic effects of S. canadensis on seed germination of P. laciniata. Overall, the inhibitory allelopathic impact of S. canadensis on seed germination of native species may be attenuated under increased and diverse N deposition, thus it could prevent its further invasion.
Following circumscribed monocular retinal lesions most cells located in the lesion projection zone (LPZ) in the cat’s primary visual cortices remain binocular but their receptive fi elds (RFs) revealed by stimulation via the lesioned eye, are displaced into proximity of the lesion. The process of topographic reorganization (adaptive learning) of the visual cortex, is based on spike timing-dependent plasticity rather than the classical Hebbian rules [Young et al. (2007) Nat Neurosci 10: 887–895]. The contrast sensitivities of the classical RFs of LPZ neurons revealed by stimulation via the lesioned eye are signifi cantly lower, while the suppresive infl uences of their “silent”, extra-classical RFs are weaker than those of their counterparts revealed by stimulation via non-lesioned eye. Other properties (e.g. orientation, spatial and temporal frequency preferences) however match well the properties of RFs revealed by stimulation via non-lesioned eye. These similarities are presumably visual experience-dependent, that is, they are related to the fact that in the post-lesion period (from adolescence to maturity), the neuronal activities originating from each retina are correlated by effectively synchronized exposure to the same visual stimuli. These results are consistent with the hypothesis that the ectopic RFs are based on enhancement of the synaptic effi cacy of long-range, excitatory intracortical connections. Financial support: Nencki Institute, Poland; NHMRC and ARC grants, Australia.
A total of 53 strains of chromium-resistant bacteria were isolated from Meiliang Bay of Taihu Lake, China and were tested for Cr(VI) resistance. The strain THKCS311 with the maximum growth value under Cr(VI) stress was regarded as the optimal strain for further study. The partial sequences were amplified from the strain and the BLAST query revealed that it was closely related to Bacillus sp., and it had 98% homologous to Bacillus mycoides strain 273 and Bacillus anthracis strain ATCC 14578. Batch experiments were conducted to remove Cr(VI) using THKCS311, and the effects of the initial Cr(VI) concentration, pH, and temperature condition on Cr(VI) removal efficiency were investigated. The results showed that Bacillus sp. can mediate reduction of Cr(VI)-Cr(III), and the removal efficiency decreased with the increase of initial Cr(VI) concentration. The removal efficiency of Cr(VI) was highest at pH 6.5 and 35ºC, and removal efficiencies were 59.2% and 60.7%, respectively. SEM micrographs indicated that THKCS311 cells were irregular and cracked with the appearance of wrinkles on the surface after Cr(VI) stress.
To achieve emission reduction targets in China, it is necessary to analyze the factors driving energyrelated carbon emissions from a regional perspective. We used extended STIRPAT model (stochastic impacts by regression on population, affluence, and technology) based on the classical IPAT identity (where I = impact representing carbon emissions, P = population, A = affluence, and T = emission intensity) to determine the main factors driving energy-related carbon emissions in Xinjiang from 1952 to 2014, an important Chinese energy base in northwestern China. Total carbon emissions in Xinjiang were found to increase from 28.51 × 10⁴ t in 1952 to 9,446.61 × 10⁴ t in 2014, representing a 331.34-fold increase over a period of 63 years. Results show that the impacts and influences of various factors on carbon emissions varied among three stages of development: “Before Reform and Opening up” (1952-1977), “After Reform and Opening up” (1978-2000), and “Western Development” (2001-2014). In the first stage, emission intensity and population size were the dominant contributors to increments in carbon emissions, while the energy consumption structure played an important role in curbing carbon emissions. In the second stage, economic growth and population size were the dominant contributors to increments in carbon emissions, while emission intensity had a significant negative effect on carbon emissions. In the third stage, fixed asset investment and economic growth were the dominant contributors to increments in carbon emissions, while emission intensity had a significant negative effect on carbon emissions.
Plant invasion succeeds because of such invader characteristics as fecundity and high-efficiency multiple reproduction modes. The acquisition of individual resources and the benefits of individual fitness are driven by optimum patterns of life history and trade-offs of reproductive allocation (RA) in plants, and variations in RA strategy play an key role in plant adaptation to environmental changes. Thus determining the RA strategy of invasive plants is important for understanding the successful mechanism underlying plant invasion. This study aims to determine the reproductive allocation (RA) strategy of two herbaceous invasive plants (Conyza canadensis and Solidago canadensis) across different cover classes in eastern China. Plant height, maximum branch length, the reproductive branch number, aboveground biomass, the amount of reproductive investment, and the coefficient of RA of the two plants decreased with increasing cover class (although the changes were not pronounced). Thus the two plants may decrease physiological investment on reproductive behavior and reduce RA under competitive conditions because of interspecies competition that progressively decreased and intraspecific competition that gradually increased with increasing cover class. The RA of the two plants may be principally influenced by plant community composition at low cover classes, but by soil pH at high cover classes. This may be the outcome that soil pH of the two plants decreased with increasing cover class significantly. Thus, intraspecific competition for resources may play an important role in the RA strategy of the two plants under high cover class.
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