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关键词： Microbial electrosynthesis   CO2 flow fluctuation   Biochemical production   CO2 valorization   Carbon capture and utilization  

摘要： Microbial electrosynthesis (MES) for CO2 valorization could be influenced by fluctuations in CO2 mass transfer and flow rates. In this study, we developed an efficient method for CO2 delivery to cathodic biofilm by directly sparging CO2 through the pores of ceramic hollow fiber wrapped with Ni-foam/carbon nanotube electrode, and obtained 45% and 77% higher acetate and methane production, respectively. This was followed by the MES stability test in response to fluctuations in CO2 flow rates varying from 0.3 ml/min to 10 ml/min. The biochemical production exhibited an increasing trend with CO2 flow rates, achieving higher acetate (47.0 +/- 18.4 mmol/m(2)/day) and methane (240.0 +/- 32.2 mmol/m(2)/day) generation at 10 ml/min with over 90% coulombic efficiency. The biofilm and suspended biomass, however, showed high resistance to CO2 flow fluctuations with Methanobacterium and Acetobacterium accounting for 80% of the total microbial community, which suggests the robustness of MES for onsite carbon conversion.

关键词： C. mrigala   Chlorfenapyr   Acetamiprid   Dimethoate   Histopathology and hematology  

摘要： The aim of the present study was to investigate the comparative effects of pesticides Chlorfenapyr, Dimethoate and Acetamiprid on the health of Cirrhinus mrigala under long term exposure. Eighty C. mrigala were divided in four equal groups;one control and three treated groups. The blood was collected from both control and treated groups at intervals of 10th, 20th and 30th days for hematobiochemistry and histopathological alterations. The result indicates significant difference (P < 0.05) in RBCs, Hb, PCV and MCHC whereas elevation in WBCs and Platelets counts were recorded. In 10th day sampling, MCV value of Dimethoate and Acetamiprid treatment had no difference in comparison with the control group, however it is significantly increased (P < 0.05) in rest of sampling. The MCH value of exposed fish showed significant increased (P < 0.05) after 20th and 30th days for Chlorfenapyr and after 30th days for Acetamiprid exposure while insignificantly increased for rest of sampling. It was also found that these pesticides significantly decrease (p < 0.05) the T3 and T4 levels while increase in the TSH, cortical, ALP, AST, ALT and LDH levels in the serum of the treated fishes in contrast to control group. Similarly, histopathological analysis of gills and liver showed significant alterations in all the treated groups. Toxicity trends of these pesticides was ranked as Chlorfenapyr Acetamiprid > Dimethoate. It is concluded that indiscriminate use of such pesticides poses a noxious threat to non-target organisms, harm the ecosystems and jeopardizes human health. (C) 2020 The Author(s). Published by Elsevier B.V. on behalf of King Saud University.

关键词： Angkor temples   Biodeterioration   Biofilms   Capillary action   Cultural heritage   Defoliation   Sandstone   Salting   Secondary minerals  

摘要： Angkor monuments/temples in the Southeast Asia are UNESCO World Cultural Heritage of the Khmer Civilization and they require preservation and protection from destruction. In this article, activityand process-based approaches are used to present the current available results on the active microorganisms and their biochemical processes associated with the biodeterioration of sandstone cultural heritage under the tropical climate in Cambodia. Such information is important for effectively protection and management. Severe deterioration of sandstone monuments is a result of weathering processes of a combination of physical, chemical and biological forces, including both natural and anthropogenic ones. Given the fact that water is an important natural factor affecting the stability of sandstone cultural heritage under the tropical regions, subsequent microbial colonization and contribution to the deterioration of sandstone have been investigated with both culture-dependent and culture-independent techniques to provide information about the microbiota associated with the sandstone. Recent data show that both sulfur and nitrogen cycles are active biochemical processes by specific microorganisms on sandstone temples/monuments in the tropical region. Both sulfur-oxidizing bacteria and fungi are active involved and, more recently, ammonia-oxidizing archaea (AOA) are implicated with higher abundance than ammonia-oxidizing bacteria (AOB) on sandstone monuments. It is clear that a research paradigm shift is taking place on microbiology of cultural heritage, and the active, and biochemically and physiologically functional microbes are focused to advance our fundamental understanding and knowledge on the biodeteriogens for a better protection and management of cultural heritage. Biochemically and physiologically functional and important microorganisms, as well as the biochemical mechanisms involved, shall be focused in order to advance the basic research on cultural heritage, while

关键词： Ecotypic differentiation   Mesophyll conductance   Optimal temperature of photosynthesis   Temperature acclimation   Temperature adaptation   Rubisco kinetics  

摘要： The temperature dependence of the light-saturated rate of photosynthesis has large interspecific and intraspecific variations, which may be related to adaptation to the habitat environment. As both higher latitude and altitude have lower habitat temperature, we addressed the question of whether temperature adaptation is similar between high-latitude and high-altitude ecotypes. We raised three ecotypes of Fallopia japonica collected from high latitude and low-altitude (Hirosaki), high-altitude and low-latitude (Fuji), and low-altitude and low-latitude (Tokyo) habitats at two growth temperatures, and determined the temperature dependence of photosynthesis and related biochemical and physical traits, including mesophyll conductance. Temperature dependence of photosynthesis and related traits differed among ecotypes, but the difference was not significant between Fuji and Tokyo when grown at a low-temperature. The simulation analysis suggested that the temperature dependence of Rubisco activity and the CO2 concentration in the chloroplasts had large contributions to the variation in the temperature dependence of photosynthesis. We conclude that both ecotypes from high-altitude and high latitude habitats tend to have a temperature dependence of photosynthesis which is adaptive to low-temperature conditions, but the mechanisms to adapt to high-altitude are not necessarily the same as compared with those to high-latitude.

关键词： Freezing tolerance   H2O2   MDA   Pistachio   Proline   Soluble carbohydrates  

摘要： This study was undertaken to compare freezing tolerance of 10 commercial Iranian pistachio cultivars in January and March, and to study the relationship between freezing tolerance and changes in the concentration of soluble carbohydrates, total soluble proteins, proline, phenolic compounds, malondialdehyde (MDA), hydrogen peroxide (H2O2), and water content of buds in both sampling stages. After subject to six different freeze-temperature tests (-9, -13, -17, -21, -25, and - 29 degrees C), bud LT(50)values were evaluated using the measurement of electrolyte leakage and bud browning. In January, 'Chrokeh,' 'Shahpasand', and 'Rezaee' showed the highest freezing tolerance, whereas 'Kaleh Ghouchi' was the least hardy cultivar. Freezing tolerance of all cultivars lessened slightly in March. In this period, 'Sefid Pesteh,' 'Shahpasand,' 'Abbas Ali,' 'Kaleh Ghouchi,' and 'Fandoghi' showed the least freezing tolerance, while 'Rezaee,' 'Momtaz,' and 'Chrokeh' were the highest hardy cultivars. There were significant differences in all the characteristics mentioned above among pistachio cultivars in both sampling dates. Negative correlations were observed between LT(50)values with proline, phenolic compounds, soluble carbohydrates, and total soluble proteins. Also, there was a positive correlation between LT(50)values with the concentration of MDA and H(2)O(2)on both dates and with bud water content in March. These results indicated osmoregulants are valuable indices to screen freezing tolerance in pistachio cultivars.

关键词： Sogatella furcifera   Insecticide resistance   Chlorpyrifos   Cytochrome P450   RNA interference  

摘要： The white-backed planthopper, Sogatella furcifera (Horvath) (Hemiptera, Delphacidae), is an energetic rice insect pest in rice production or rice-growing areas. Due to excessive use of the chemical insecticide, S. furcifera has produced the high resistance to some frequently used insecticides. In this paper, the resistance levels of S. furcifera from the eight different areas of Sichuan Province against the five chemicals were monitored by using the rice seedling dipping during 2017-2018 to understand the resistance levels. The results showed that most of all populations have developed low or moderate level of resistance for chlorpyrifos (3.4 to 44.3-fold) and thiamethoxam (3.9- to 15.5-fold), the populations in the LS (1.7 to 5.4-fold)and WS (1.6 to 5.0-fold) regions were still sensitive or low resistance levels compared with other local populations. Almost all populations displayed the susceptible to imidacloprid (0.9- to 5.0-fold), buprofezin (0.9- to 4.3-fold) or low levels of resistance to pymetrozine (1.5- to 6.8-fold). The synergism experiment indicated that P450 enzymes may be important contributed to the metabolic detoxification of chlorpyrifos. The cross-resistance bioassay showed that there was no cross-resistance between chlorpyrifos and triflumezopyrim, but for sulfoxaflor, in the XY17 population. The relative expression level of twelve insecticide resistant-related P450 genes were analyzed by using qRT-PCR and found that CYP4C77, CYP418A1, CYP418A2, CYP408A3 and CYP6ER4 were significantly more expressed in the 3rd-instar nymph of the XY17 and XY18 field populations. To determine the main resistant-related P450 gene for chlorpyrifos, the relative expression level of five P450 genes were detected by using qRT-PCR from the G2 and G4 generation of XY17 under the pressure with LC50 of chlorpyrifos. The results showed that CYP6ER4 was significantly up-regulated expression in XY17 G2 and G4 generations population over 700-fold (P < 0.01). The full length and

关键词： Marine mysid   Microplastic   Growth   Population   20-Hydroxyecdysone   Oxidative stress  

摘要： In this study, a marine mysid, Neomysis awatschensis, was exposed to 1 x 10(3)-5 x 10(5) particles mL(-1) of polystyrene microbeads (1 and 10 mu m). Exposure to microplastics (MPs) resulted in ingestion and egestion in feces. MPs exposure during the early stage resulted in mortality and oxidative stress, while more mature stages were increasingly tolerant to MPs. Feeding rates were inhibited by MPs, and age-specific oxidative stress was observed. Growth parameters were significantly affected by MPs with lower 20-hydroxyecdysone (20E) concentrations and longer intermolt durations. The number of hatched juveniles from females that were exposed to MPs was significantly lower than the control treatment, but no significant differences were observed between survival rates of newly hatched juveniles in the different treatments. Our results suggest that the detrimental effects of prolonged exposure to MPs could be age- and size-specific and harmful for the maintenance of mysid populations.

关键词： p(HEMA-GMA) cryogel   Immobilization   L-asparaginase   Enzyme stability  

摘要： Cryogels have recently been attracted intense attention as suitable carriers for enzyme immobilization. Herein, L-asparaginase was selected as the model enzyme due to its application such as pharmaceutical and food. Under optimum conditions, L-asparaginase was immobilized on poly (2-hydroxyethyl methacrylate-glycidyl methacrylate) cryogels with 68.8% of immobilization yield and 69.3% of activity recovery. The immobilized enzyme exhibited improved stability with respect to the soluble enzyme at extreme conditions, especially around acidic pH and high temperature. Also, the storage stability and reusability of the immobilized enzyme were found to be approximately 54% and 52% of the original activity after 28 days at room temperature and 10 cycles, respectively. The thermodynamic studies indicated that activation energy (E-a) of the free enzyme decreased from 13.08 to 10.97 kJ/mol, which means an increase in the thermostability of L-asparaginase. The Michaelis-Menten constants (K-m) of 2.04 and 1.67 mM, and the maximum reaction rates (V-max) of 170.0 and 115.0 mu M min(-1) were estimated for soluble and immobilized L-asparaginase, respectively. These findings demonstrated that the designed cryogels turn out to be a good carrier matrix for L-asparaginase immobilization with high catalytic efficiency and enhanced stability.

关键词： Ananas comosus (L   ) merr   Transgenic   Field performance   Side effects  

摘要： Key messageVariations brought about by pineapple genetic transformation do not appear to be physiologically significant in fruitsAbstractIn terms of tropical fruit production, pineapple ranks as one of the major commercially grown fruit crops globally. Our previous research led to the development of a technique suitable for genetic modification of pineapple. The transgenic plants generated were characterized following hardening-off and during the subsequent 8 years of in-situ growth. The current work focuses on the results of a comparison of selected fruit mesocarp physical and biochemical (indicators related to oxidative metabolism) traits across untransformed control plants propagated by cutting, micropropagated untransformed control plants, and micropropagated genetically transformed plants. At the fruit ripening stage, the statistical analysis revealed no biologically meaningful differences in fruit mass (with tops included) (c. 2.0 kg) between transgenic and both groups of control plants. Moreover, contents of aldehydes, soluble phenolics, shikimic acid, phenylalanine, tyrosine, and p-coumaric acid were statistically comparable across the three groups. However, there were small but significant differences in the content of chlorophylls (a, b), carotenoids, malondialdehyde, proteins, 1,1-diphenyl-2-picrylhydrazyl, and cell wall-linked phenolics. This also included small changes in the levels of enzymes (i.e. superoxide dismutase and peroxidase). Furthermore, fruits from micropropagated control plants showed 2.2-fold more catalase activity than control plants propagated by cutting and transgenic plants;transgenic fruits contained 1.8-fold more caffeic acid than those from macropropagated and micropropagated control plants;fruits from micropropagated control plants and transgenic plants showed 3.9-folds higher ferulic acid content than macropropagated control plants;fruit sinapic acid content was 2.5-fold higher in micropropagated control plants than in transgenic