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The Palaearctic genus Shadelphax Ding, 2006 (Hemiptera: Fulgoromorpha: Delphacidae: Delphacinae: Delphacini) is taxonomically reviewed to include two species: S. eforiae (Dlabola, 1961) (China: Neimenggu, Ningxia, Gansu, Qinghai and Xinjiang; Mongolia; Kazakhstan; Ukraine; Middle Asia) and S. kashiensis sp. nov. (China: Xinjiang). The genus Shadelphax is redefined. The main morphological characters including the male genitalia of the two species are described or redescribed and illustrated.
A protocol for regeneration of Gentiana straminea Maxim recently established in our laboratory, somatic embryogenesis was obtained from its leaf derived calli. The gentiopicroside contents of embryogenic calli, globular-, heart-, torpedo-, and cotyledon-shaped embryoids as well as regenerated plantlets were determined by high-performance liquid chromatography. Gentiopicroside was detectable in all materials tested. Embryogenic calli showed the lowest gentiopicroside content. The changes of gentiopicroside contents were not significant (P<0.05) with the development of somatic embryos. The highest gentiopicroside content (30.7 mg g⁻¹ dry weight) was achieved in regenerated plantlets. The contents of gentiopicroside were not significant (P<0.05) differences between control plants and embryogenic calli, different stages of somatic embryos and regenerated plantlets. This protocol could be employed for producing gentiopicroside or other medicinal compounds.
The genus Malaxa Melichar, 1914 (Hemiptera: Fulgoroidea: Delphacidae: Tropidocephalini) feeding exclusively on bamboo (Bambusoideae), containing 4 species: M. delicata Ding et Yang, 1986 (Guizhou: Guiyang; Yunnan: Mongban; Zhejing: Hangzhou; Fujian: Huangkeng), M. hunanensis Chen sp. nov. (Hunan: Zhangjiajie), M. fusca Yang et Yang, 1986 (Taiwan: Nantou) and M. semifusca Yang et Yang, 1986 (Taiwan: Nantou; Hualian; Guizhou: Daozhen) from China is here reviewed. The male of M. fusca Yang et Yang, collected from Nantou County of Taiwan, is reported and described for the first time. The main morphological characters and male genitalia of 4 species are described and illustrated. A key to species in the genus from China is provided.
Since a decade, the large-scale commercial production of Siratia grosvenorii plantlets is being practiced through in vitro culture of its microcuttings, but it has some drawbacks such as handling of plantlets, low transplant-survival rate, development of massive callus, low yield after transplantation, etc. An experiment has been conducted to improve the prevailing technique as well as to develop a new ex vitro technique to overcome these drawbacks. Several concentrations of naphthalene acetic acid (NAA) (0–4.0 mg/l) have been tried with the MS (Murashige and Skoog in Physiol Plant 15:473–479, 1962) basal medium containing 3% (w/v) sucrose and 4.0 g/l agar, out of which 0.1 mg/l NAA was found best in terms of smaller diameter of callus and maximum rooting and transplant survival rate. Further, use of perlite instead of agar medium also showed possibilities for future research on commercial-scale plantlet production. Ex vitro rooting technique was found superior to the in vitro one as plantlets developed through this method had lateral roots without any callus at the base of microcuttings, just like the natural root system and of course with higher root length, rooting rates, and transplant survival rate compared to the in vitro developed plantlets. Further, this technique is economical in terms of labor and time saving and gives rise to vigorous plants which ultimately bring higher yields and profits.
Carbonaceous greenhouse gases (i.e., CO₂, CH₄ ) have often reported to be emitted from the surfaces of reservoirs, while other non-carbonaceous greenhouse gases are not available to many reservoirs. In this study, the spatiotemporal variability of N₂O emissions from Xin’anjiang Reservoir was investigated at the different regions over a 13-month period using the method of the static floating chambers combined with gas chromatography. Results showed that the average N₂O emission flux was the highest in the downstream river (220.24±153.68 μg m⁻²·s⁻¹), followed by the upstream river (49.85±48.55 μg m⁻²·s⁻¹). The reservoir’s main body had the lowest flux (26.61-39.07 μg m⁻²·s⁻¹). Seasonal variability indicated that the average N₂O emission fluxes before the dam reached their maximum in March, which was likely influenced by the disappearance of thermal stratification then, caused a short N₂O flux peak at the water-air interface. A thorough investigation should be carried out at the different reservoir regions for a long-term basis to discover the spatiotemporal variability in N₂O emission flux in a hydroelectric reservoir system, which could avoid the error of estimating the N₂O emissions incorrectly.
Chelant-induced phytoextraction is considered an ideal remedial technique for removing heavy metals from contaminated soils. However, it can increase the risk of adverse environmental effects due to increased metal mobilization and the persistence of both chelants and metal-chelant complexes for extended periods of time. This paper reviews the mechanism, potential risks, and optimization of chelant-induced phytoextraction of toxic metals from contaminated soils. The advantages and major drawbacks of phytoextraction, along with possible strategies to reducing the risks associated with chelant application, are reviewed. Moreover, the directions for future research on chelant-assisted phytoextraction are briefly discussed. The objective of this paper was to comprehensively review chelant-assisted phytoextraction, and it will provide an effective and safe remediation technology for heavy metal-contaminated soils.
The paper determined the volume ratio of the main hull and side hull and their position characteristic parameter of operation and maintenance trimaran. Numerical simulation technology was used to do the analysis and calculation of trimarans which have different volume ratio of the main and side hull, and on this basis, the paper tried different positions of main and side hull, finally got the trimaran with optimum resistance performance and the chart of trimaran resistance estimation, so as to provide a new way in the selection of feature parameter of offshore wind farm maintenance trimaran and its resistance estimation
Multiplex PCR is a variant of conventional PCR which includes two or more pairs of primers in a single reaction to amplify corresponding genes simultaneously. In this study, a reliable multiplex PCR analysis protocol was established for simple and fast detection of transgenes in plant materials. Two pairs of primers, corresponding to neomycin phosphotransferase gene and 1-aminocyclopropane-1-carboxylate synthase gene, were selected for target and resident gene respectively. The method bypasses routine DNA extraction, requires only very little amount of plant tissue and produces reliable results as shown by successful discrimination of transformed and non transformed tobacco, tomato and kumquat materials. The method facilitates early identification of transgenic buds when they are still quite small.
Heavy metal distribution in aquatic ecosystems can be influenced by a variety of factors. In this study, the spatial distribution and seasonal variation of heavy metals (Cd, Ni, Cu, Zn, Cr, and Pb) in lake water and sediments of different lake zones of a large, shallow, eutrophic freshwater lake, Taihu Lake, were investigated. Metal concentrations in the river water, bloom assemblages, and macrophyte materials were also determined. The results demonstrated that metal distribution in Taihu Lake showed distinct patterns in different seasons. Metal concentrations in rivers around Taihu Lake showed some peaks that may contribute to the elevated metal concentrations in lake water and sediments. However, the metal concentrations in the river water did not fluctuate significantly with months (March, July, and December). The dissolved metal concentrations in the phytoplankton-dominated zone of the lake were significantly higher than those in the macrophyte-dominated lake zone in summer, which could be attributed to the different dominated primary producers in the two lake zones. Statistical analysis results demonstrated that the dissolved metal concentrations were positively correlated with water turbidity for all metals in July. However, the positive correlations disappeared for most metals of March and December samples. The results of this study could provide useful information for further understanding of the transportation and fates of heavy metals in different freshwater lake ecosystems.
Composting of poultry manure (PM) can cause several problems, including ammonia (NH₃) emissions. Biochar is a useful material in the composting process due to its microstructure and sorption properties. This research aims to investigate the changes in NH₃ emissions and its relationship with physicochemical properties and the bacterial community during PM composting with different biochar. Seven treatments were carried out with a 2:1 ratio of PM and corn leaf (dry weight basis), i.e. compost with no biochar (control); compost with 5%, 10% and 15% wheat stalk biochar (WSB); and compost with 5%, 10% and 15% rice husk biochar (RHB). The results indicated that adding WSB and RHB could obviously (p<0.05) reduce NH₃ emissions by 53.4-88.7% and 62.5-89.3%, respectively. And the volatilization of NH₃ in RHB treatment was lower than that in WSB treatment at the same ratio. Higher surface areas of RHB could adsorb more NH₄⁺ and NH₃ to reduce the volatilization of NH₃ at the thermophilic composting stage. The analysis of the bacterial community in compost indicated that adding biochar could decrease the population of Ureibacillus thermosphaericus involved in the oxidative deamination process, which further reduced the NH₄⁺-N content and the emission of NH₃. Thus, RHB is suggested to be added into PM composting with a ratio of 15%.
The complete coding sequences of 3 porcine genes -ASPA, NAGA, and HEXA - were amplified by the reverse transcriptase polymerase chain reaction (RT-PCR) based on the conserved sequence information of the mouse or other mammals and referenced pig ESTs. These 3 novel porcine genes were then deposited in the NCB1 database and assigned GeneIDs: 100142661,100142664 and 100142667. The phylogenetic tree analysis revealed that the porcine ASPA, NAGA, and HEXA all have closer genetic relationships with theASPA, NAGA, and HEXA of cattle. Tissue expression profile analysis was also carried out and results revealed that swine ASPA, NAGA, and HEXA genes were differentially expressed in various organs, including skeletal muscle, the heart, liver, fat, kidney, lung, and small and large intestines. Our experiment is the first one to establish the foundation for further research on these 3 swine genes.
Autophagy can be regarded as a protection mechanism to restrict programmed cell death (PCD) induced by pathogen infection during plant innate immunity in the early stages. Autophagy related 5 (ATG5) plays an important role in autophagy in Arabidopsis. We investigated the function of ATG5 in Arabidopsis in the hypersensitive response (HR)-PCD elicited by both virulent and avirulent strains of Pseudomonas syringae pv. tomato bacteria DC3000. Results show that ATG5 plays a vital role in limiting HR induced by P. syringae strains and colocalizes with autophagic bodies during the early phase of bacterial infection. In addition, the P. syringae-induced response is mediated by the salicylic acid (SA) signaling pathway. In summary, ATG5 is required for limiting HRPCD induced in Arabidopsis by P. syringae strains and may be mediated by SA signaling.
The Arabidopsis Ethylene-Insensitive3 (EIN3) has received attention recently and has been shown to be involved in the regulation of multitude of responses ranging from biotic stress defense and development to hormone interaction. To better understand the roles of EIN3 in plants response to salinity stress during germination and postgermination development, seeds of two EIN3 deficient mutant and a EIN3 overexpression mutant of Arabidopsis were analyzed under salinity and compared with Col-0 as control. The results showed that the ein3-1eil1-1 double mutant (lacking EIN3 and EIN3-Like1) and ein3-1 (lacking EIN3) were hypersensitive to high salinity ([150 mM NaCl), while EIN3 overexpression mutant (EIN3ox) displayed enhanced tolerance, indicating that EIN3 plays important roles during seed germination under salinity. In addition, we also found that the two EIN3 deficient mutant seedlings accumulate high levels of hydrogen peroxide (H2O2), which was thought to be an inhibitor of germination under salinity before, suggesting that EIN3 may function as a negative regulator of reactive oxygen species metabolism in germinating seeds under salinity. Taken together, our studies provide insights that EIN3 promotes seed germination under salinity, at least in part, through modulating concentration of H2O2 in germinating seeds.
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