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31.
The degree of technological change biased to the environmental factor is crucial to industrial sustainable development. Using the stochastic frontier analysis method based on the translog production function and the panel data of 32 industrial sub-sectors in Shanghai over 1994–2011, this paper combines the evolution dynamic of the frontier technological structure with the evolution dynamic of technological change direction to estimate the output elasticities of production factors and the growth rate of green total factor productivity. Also, we investigate and compare the degrees of technological change biased to four production factors, i.e., capital, labor, energy, and carbon emissions. The results show that the industrial green total factor productivity in Shanghai presents an overall upward trend and mainly depends on the technical efficiency change. The improvements of labor productivity, R&D intensity, and energy efficiency can effectively enhance the green technical efficiency, while capital deepening has a mitigation effect on the green technical efficiency. The technological change of Shanghai's industrial production biases to energy use and capital saving, causing a high energy demand of industrial development. Under the dual impacts of economic development and energy-saving and emission-reduction policies, the degree of technological change biased to the environmental factor (carbon emissions) displays strong and weak alternations, indicating that the green bias of industrial technological change in Shanghai is not stable and that the green transformation of industrial development model needs to be further advanced.  相似文献   
32.
Green tea contains active ingredients which are beneficial for health. While numerous studies have been conducted on the components extracted from green tea, few studies have investigated the active ingredients in tea residue. In this study, proteins were extracted from green tea residue via an optimised alkaline extraction combined with enzymatic hydrolysis, of which, an acidic protease was selected to prepare an enzymatic hydrolysate because of its high angiotensin converting enzyme (ACE) inhibitory activity. The composition characteristics of extracted green tea proteolysis products were elucidated, including amino acid composition, molecular weight distribution and possible amino acid sequences. In addition, the protein hydrolysate had anti-digestive properties, maintained its activity of inhibiting ACE enzyme at different temperatures, pH and metal ions, and exhibited antihypertensive activity in animals. In conclusion, the optimised alkaline extraction and enzymatic hydrolysis conditions of a ACE inhibitory peptide from green tea residue is an optimal extraction method to maintain its antihypertensive activity, providing the basis for the clinical application of green tea for blood pressure reduction.  相似文献   
33.
The synthesis of Zinc oxide nanoparticles using a plant-mediated approach is presented in this paper. The nanoparticles were successfully synthesized using the Nitrate derivative of Zinc and plant extract of the indigenous medicinal plant Cayratia pedata. 0.1 mM of Zn (NO3)2.6H2O was made to react with the plant extract at different concentrations, and the reaction temperature was maintained at 55 °C, 65 °C, and 75 °C. The yellow coloured paste obtained was wholly dried, collected, and packed for further analysis. In the UV visible spectrometer (UV–Vis) absorption peak was observed at 320 nm, which is specific for Zinc oxide nanoparticles. The characterization carried out using Field Emission Scanning Electron Microscope (FESEM) reveals the presence of Zinc oxide nanoparticles in its agglomerated form. From the X-ray diffraction (XRD) pattern, the average size of the nanoparticles was estimated to be 52.24 nm. Energy Dispersive Spectrum (EDX) results show the composition of Zinc and Oxygen, giving strong energy signals of 78.32% and 12.78% for Zinc and Oxygen, respectively. Fourier Transform - Infra-Red (FT-IR) spectroscopic analysis shows absorption peak of Zn–O bonding between 400 and 600 cm?1. The various characterization methods carried out confirm the formation of nano Zinc oxide. The synthesized nanoparticles were used in the immobilization of the enzyme Glucose oxidase. Relative activity of 60% was obtained when Glucose oxidase was immobilized with the green synthesized ZnO nanoparticles. A comparative study of the green synthesized with native ZnO was also carried out. This green method of synthesis was found to be cost-effective and eco-friendly.  相似文献   
34.
A convenient method for the ‘one-pot’ synthesis of novel target molecule 2,7-diaryl-[1,4]-diazepan-5-ones from the respective 2,6-diaryl-piperidin-4-ones was catalyzed by NaHSO4.Al2O3 heterogeneous catalyst in dry media under microwave irradiation in solvent-free conditions. Moreover, the catalyst could be recovered and re-used up to 4 times after washing with ethyl acetate. They were evaluated for potential antibacterial activity against Staphylococcus aureus, β-Haemolytic streptococcus, Vibreo cholerae, Salmonella typhii, Escherichia coli, Klebsiella pneumonia, Pseudomonas and antifungal activity against Aspergillus flavus, Aspergillus fumigatus, Mucor, Candida albicans and Rhizopus. Structure-Activity Relationship (SAR) led to the conclusion that, of all the compounds 25–32 tested, compound 30 exerted strong in vitro antibacterial activity against S. aureus, S. typhii, and Pseudomonas and all the compounds 25–32 were less active against E. coli, whereas all the compounds 25–32 displayed potent in vitro antifungal activity against all the fungal strains used, except compound 30, which was more effectual against Mucor.  相似文献   
35.
Abstract

Objectives

Regular intake of green tea associates with lower DNA damage and increased resistance of DNA to oxidant challenge. However, in vitro pro-oxidant effects of green tea have been reported. Both effects could be mediated by hydrogen peroxide (H2O2) which is generated by autoxidation of tea catechins. In large amounts, H2O2 is genotoxic, but low concentrations could activate the redox-sensitive antioxidant response element (ARE) via the Keap-1/Nrf2 redox switch, inducing genoprotective adaptations. Our objective was to test this hypothesis.

Methods

Peripheral lymphocytes from healthy volunteers were incubated for 30 minutes at 37°C in freshly prepared tea solutions (0.005, 0.01, 0.05%w/v (7, 14, 71 µmol/l total catechins) in phosphate buffered saline (PBS), with PBS as control) in the presence and absence of catalase (CAT). H2O2 in tea was measured colorimetrically. Oxidation-induced DNA lesions were measured by the Fpg-assisted comet assay.

Results

H2O2 concentrations in 0.005, 0.01, and 0.05% green tea after 30 minutes at 37°C were, respectively, ~3, ~7, and ~52 µmol/l. Cells incubated in 0.005 and 0.01% tea showed less (P < 0.001) DNA damage compared to control cells. Cells treated with 0.05% green tea showed ~50% (P < 0.001) more DNA damage. The presence of CAT prevented this damage, but did not remove the genoprotective effects of low-dose tea. No significant changes in expression of ARE-associated genes (HMOX1, NRF2, KEAP1, BACH1, and hOGG1) were seen in cells treated with tea or tea + CAT.

Conclusion

Genoprotection by low-dose green tea could be due to direct antioxidant protection by green tea polyphenols, or to H2O2-independent signalling pathways.  相似文献   
36.
Abstract

The cotton aphid, Aphis gossypii Glover was found to be the only aphid species infesting the tested roselle varieties (Sudani, Masri and White), Hibiscus sabdariffa L. which were cultivated in El-Kanater El-khayria (about 30 km north Cairo) as ex situ old land. The vertical distribution of the whitefly, Bemisia tabaci (Genn.); the leafhopper, Empoasca spp. and the pink hibiscus mealy bug, Maconellicoccus hirsutus Green, as insect pests attacking this crop had been studied. Moreover, certain morphological characters and amino acids concentrations in the three varieties of roselle, were obtained. The obtained results indicated that the experimental insect pests severely attacked leaves of the stem nodes from the 8th to the 11th (counting from the top of the plant), whereas whitefly were more abundant on these nodes. All tested insect species were less abundant on the 4th stem node. This may be due to the extensive existence of gland hairs, that excrete some compound especially phenols that might prevent the insects from reproducing on the leaves. The opposite was, however, true for M. hirsutus as it did not attack Sudani and Masri varieties but the infestation occurred at the highest level on the White variety.  相似文献   
37.
Temperate forests are characterised by variable light quality (i.e. spectral composition of light) at or near the forest floor. These understory environments have a high concentration of green light, as red and blue light are preferentially absorbed by upper canopy leaves. Understory species may be well-adapted for using green light to drive photosynthesis. Angiosperms have been shown to use green light for photosynthesis, but this ability has not been demonstrated in shade-dwelling bryophytes. In this study, net photosynthetic rate (PN) of three temperate understory species of moss (Dichodontium pellucidum (Hedw.) Schimp., Leucobryum albidum (Brid. ex P.Beauv) Lindb. and Amblystegium serpens (Hedw.) Schimp.) was measured under green, red?+?blue, and red?+?blue?+?green light to assess green light use efficiency. All three species were capable of photosynthesising beyond their respiratory demands using solely green light, with higher green light use efficiency measured in plants collected from areas with greater canopy cover, suggesting growth in a green light concentrated environment increases green light use efficiency. Each species was also collected from sites differing in their degree of canopy cover and grown under three light treatments (high light, low light, and green light). Photosynthetic efficiency (chlorophyll fluorescence), tissue nitrogen and carbon isotope concentrations were assessed after a short growth period. Growth conditions had little effect on leaf chemistry and monochromatic green light did not significantly degrade photosynthetic efficiency. This study provides the first evidence to date of positive net ‘green light photosynthesis’ in mosses.  相似文献   
38.

The green alga Botryococcus is an important component of the phytoplankton in lake sediments from the Rotliegend of Central Europe. The first microscopic fossils from the Saar‐Nahe Basin that can be assigned to this genus are described and illustrated here. Their distribution at various stratigraphic levels shows that the primary production of the lakes was at least partially controlled by these green algae. The frequency of fossils in the sediments is correlated with grain size, which varied with the depositional environment. Their abundance is greater in sediments deposited in shallow water, especially in small lakes and in the littoral environments of larger lakes. Sediments of deep‐water lake bottoms contain only minor amounts of algal remains. The abundance of kerogen originating from phytoplankton and occurrences of Botryococcus fossils are correlated in these lake deposits.  相似文献   
39.
Adverse conditions in the acid mine drainage (AMD) system at the Green Valley mine, Indiana, limit diatom diversity to one species, Nitzschia tubicola. It is present in three distinct microbial consortia: Euglena mutabilis-dominated biofilm, diatomdominated biofilm, and diatom-exclusive biofilm. E. mutabilis dominates the most extensive biofilm, with lesser numbers of N. tubicola, other eukaryotes, and bacteria. Diatom-dominated biofilm occurs as isolated patches containing N. tubicola with minor fungal hyphae, filamentous algae, E. mutabilis, and bacteria. Diatom-exclusive biofilm is rare, composed entirely of N. tubicola.

Diatom distribution is influenced by seasonal and intraseasonal changes in water temperature and chemistry. Diatoms are absent in winter due to cool water temperatures. In summer, isolated patchy communities are present due to warmer water temperatures. In 2001, the diatom community expanded its distribution following a major rainfall that temporarily diluted the effluent, creating hospitable conditions for diatom growth. After several weeks when effluent returned to preexisting conditions, the diatom biofilm retreated to isolated patches, and E. mutabilis biofilm flourished.

Iron-rich stromatolites underlie the biofilms and consist of distinct laminae, recording spatial and temporal oscillations in physicochemical conditions and microbial activity. The stromatolites are composed of thin, wavy laminae with partially decayed E. mutabilis biofilm, representing microbial activity and iron precipitation under normal AMD conditions. Alternating with the wavy layers are thicker, porous, spongelike laminae composed of iron precipitated on and incorporated into radiating colonies of diatoms. These layers indicate episodic changes in water chemistry, allowing diatoms to temporarily dominate the system.  相似文献   
40.
Meeting reports     
This investigation documents the formation of Green Rust (GR) and immobilization of Ni 2+ in response to bacterial reduction of hydrous ferric oxide (HFO). In the absence of Ni 2+ , 79% of the total Fe(III) present as HFO was reduced; at 10 -3 and 10 -4 M Ni 2+ , 36% of the total Fe(III) was reduced, whereas 45 to 50% of the total Fe(III) was reduced at 10 -5 M Ni 2+ . The inhibitory effect of 10 -3 and 10 -4 M Ni 2+ on Fe(III)-reduction corresponded to a 50% decrease in number of viable cells relative to the Ni 2+ -free condition, and a 25% decrease at 10 -5 M Ni 2+ . A prominent GR peak at d = 10.9 nm was evident in X-ray diffraction patterns of postreduction residual solids from the cultures. Minor peaks arising for vivianite and magnetite were also present. In samples prepared for scanning electron microscopy, thin hexagonal plates of GR were easily distinguished as a solid phase transformation product of HFO. Small hexagonal sheets and fragments of larger GR plates were also observed in transmission electron microscopy whole mounts together with bacteria that were mineralized by surface precipitates of microcrystalline magnetite. Energy dispersive spectroscopy (EDS) confirmed that GR contained Fe and P, as well as Ni in those samples taken from the Ni 2+ -amended experiments. EDS detected neither P nor Ni in the magnetite precipitates associated with the bacterial cells. Dissolved Ni2 + concentrations decreased in an exponential fashion with respect to time in all experimental systems, corresponding to an overall first-order rate constant k of -0.030 day -1 . At the same time, a strong linear relationship (r 2 = 0.99) between the dissolved and solid phase Ni 2+ /Fe 2+ ratios over the entire period of the Fe(III)reduction experiments provided evidence that the solid-phase partitioning of Ni 2+ in GR extended from equilibrium solid-solution behavior.  相似文献   
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