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Dry-hot valley is characterized by water deficit and heat stress which often occur simultaneously in the field. Nouelia insignis has become endangered and natural regeneration of the species in the dry-hot valley is limited. Seedlings subjected to each water deficit treatment (achievement by withholding irrigation for 0, 3 and 6 days, respectively) were randomly divided into three groups and transferred to climate chambers set at 25, 40 and 50 °C for 1 h, respectively. Leaf relative water content, photosynthetic activity and maximum quantum yield of photosystem II (Fv/Fm) determined after 1 day of recovery were decreased significantly, but pigment content and catalase (CAT) activity increased significantly under severe water deficit or extreme heat. Soluble sugar content increased significantly under severe water deficit or moderate heat stress. Significant interactive effects between water deficit and heat were found in leaf relative water content, Fv/Fm, non-photochemical quenching coefficient (NPQ), CAT activity and soluble sugar content. Fv/Fm of seedlings treated at combination of 50 °C and water deficit did not recover to the original level after 1 day of recovery. In conclusion, both severe water deficit and heat stress could lead to water loss of leaves and adversely affect plant metabolic activities of N. insignis. Particularly, the effects were aggravated when severe water deficit and extreme heat occurred simultaneously. Water deficit and heat, particularly their combination, might be the key factors which limited natural regeneration of N. insignis in the dry-hot valley.
Cabin placement layout is an important part of ship cabin layout design. A good cabin placement layout can improve the efficiency of the ship’s cabin arrangement. However, optimisation of the layout of cabin placement is not widely studied and more often relies on the experience of the staff. Thus, a novel methodology combining systematic layout planning and a genetic algorithm to optimise the cabin placement is presented in this paper. First key elements are converted by a systematic planning method that is often applied in factory layout, and a preliminary cabin placement layout model is established according to these key elements. Then the circulation strength and adjacency strength are taken as sub-objectives to establish a mathematical model, and an improved genetic algorithm is used to optimise the model. The result of the optimisation is compared with the initial schemes to verify the validity of the algorithm. Finally, the human factors are introduced according to the actual situation. The AHP method is used to select the layout scheme of the cabin that is most likely to be applied in the actual cabin layout
In this study, using the quadratic saturation 310 D-optimal design method, we examined the effect of kinetin (KT), gibberellic acid (GA), and naphthalene acetic acid (NAA) on microrhizome production in ginger. The effect of GA on rhizome induction was larger than that of KT or NAA. Using simulation and optimality selection for tissue culture, we found that concentrations of GA, KT, and NAA of 1.33–2.35, 0.49–0.66, and 0.62 g/l, respectively, gave a microrhizome weight of over 0.25 g. The optimal conditions for microrhizome production were 80 g/l sucrose, 2 9 MS macro-elements, and 1 9 MS microelements, with a photoperiod of 24L:0D (light/dark). At the same time, 100% survival could be achieved on transfer of the in vitro ginger plantlets with microrhizomes to soil.
This study investigated the uptake capacity and bioaccumulation of heavy metal (Cu) in water using eight different aquatic plant species: Juncus effusus, Acorus calamus, Eichhornia crassipes, Sagittaria sagittifolia, Arundina graminifolia, Echinodorus major, Nymphaea tetragona and Pistia stratiotes. The results showed that Eichhornia crassipes and Pistia stratiotes have the best ability for bioaccumulation, while Arundina graminifolia, Nymphaea tetragona, and Acorus calamus also showed good bioaccumulation. However, Juncus effusus, Sagittaria sagittifolia, and Echinodorus major displayed very weak bioaccumulation. The enrichment capacity for Cu²⁺ in roots and shoots differed among species. Most of the Cu²⁺ was located in the shoot tissues of Juncus effuses, while for Sagittaria sagittifolia and Acorus calamus it accumulates in their root tissues. However, in the case of Echinodorus major the accumulation of copper content in root and shoot tissues is the same. The adsorption rates of heavy metal Cu in different aquatic plants were different. The adsorption rates of Eichhornia crassipus, Pistia stratiotes, Echinodorus major, and Nymphaea tetragona were higher than for Juncus effusus, Sagittaria sagittifolia, and Acorus calamus. When different aquatic plants reached the adsorption equilibrium, pH values were different. The Cu enrichment amount in aquatic plants was related to the content of lignin in plants, and the higher the content of lignin, the greater the amount of copper.
An in vitro plant regeneration system was established from the spores of Pteris vittata and identification of its tolerance, and accumulation of gametophytes and callous, to arsenic (As) and copper (Cu) was investigated. The highest frequency (100%) of callus formation was achieved from gametophyte explants treated with 0.5 mg l⁻¹ 6-benzylaminopurine (6-BA) + 0.5 mg l⁻¹ gibberellin acid (GA). Furthermore, sporophytes were differentiated from the callus tissue derived from gametophyte explants on MS medium supplemented with 0.5 mg l⁻¹ 6-BA, 0.5–1.0 mg l⁻¹ GA and additional 300 mg l⁻¹ lactalbumin hydrolysate (LH) for 4 weeks. The optimum combination of ½ MS + 1.0 mg l⁻¹ GA + 0.5 mg l⁻¹ 6-BA + 300 mg l⁻¹ LH promoted sporophyte formation on 75 ± 10% of the callus. Every callus derived from gametophyte explants could achieve 3–4 sporophytes. The in vitro growth of gametophyte and callus was accelerated in the medium containing Na3AsO4 lower than 0.5 mM, but this growth was inhibited with 2 mM Na3AsO4. And with the increase of Na3AsO4 in the culture medium from 0 to 2 mM, the As accumulation in gametophytes and callus increased and achieved a level of 763.3 and 315.4 mg kg⁻¹, respectively. Gametophytes and calluses transplanted to culture medium, supplemented with different concentrations of CuSO4, are similar to those in Na3AsO4, and the Cu accumulation in gametophytes could achieve 7,940 mg kg–1 when gametophytes were subcultured in medium containing 3 mM CuSO4. These results suggested that the high efficiency propagation system could be a useful and rapid means to identify other heavy metal tolerance and accumulation. Further, the regeneration ability of callus made it possible for genetic transformation of this fern.
We examined the effects of artificial warming on physiological, biochemical, and structural changes in leaves of maize plants (Zea mays L.) with a field warming experiment in the North China Plain. Stomatal characters, leaf anatomy and ultrastructure, gas exchange, and carbohydrate and mineral nutrition concentrations were examined using light microscopy, electron microscopy, portable photosynthesis system (Licor-6400), and inductively coupled plasma atomic emission spectroscopy. We found that artificial warming (about 2 ºC) increased both the stomatal index and stomatal size, and thus increased net photosynthesis rate (A), stomatal conductance (gs), and transpiration rate (E). Artificial warming also significantly increased the profile area of chloroplast and mitochondria, but decreased leaf width and thickness, mesophyll thickness, and mesophyll cell size (mainly palisade cell size). In addition, artificial warming also significantly increased the foliar C:N ratio and soluble sugar contents (glucose, fructose, and sucrose), but not the mineral nutrients and starch contents. Our findings suggest that future global warming may affect the maize growth and production in northern China due to the direct warming effects on the structures (anatomy and ultrastructure), biochemical properties and gas exchanges of the maize leaves.
Counterfeit seeds cause a large loss in seed industry and crop production. Present study was undertaken to find a new anti-counterfeiting technology by labeling seeds with a fluorescent compound, safranine T (ST). Response surface analysis (RSA) experiment with two factors (ST concentration and seed soaking time) of 14 combinations was performed to investigate the ST effects on seed vigor and fluorescence showing in seedlings of two tobacco varieties, MS Yunyan 85 and Honghua Dajinyuan. After soaking in ST solutions, tobacco seeds were germinated for 16 days, then the germination index (GI), vigor index (VI), length of roots and shoots were determined. The optimum combinations of ST concentration and soaking time on GI, VI and length of shoots and roots were 0.57–0.69 mg/ml and 6.77–9.34 h for MS Yunyan 85 and 0.51–0.80 mg/ml and 5.81–7.39 h for Honghua Dajinyuan, respectively. Meanwhile, tobacco seedlings, treated with ST solutions from 0.3 to 1.5 mg/ml showed obviously fluorescence under illumination of green light. It suggests that soaking tobacco seeds in safranine T solution of suitable concentration can be used as a labeling technique for anti-counterfeiting in tobacco seeds.
In this paper, we report for the first time on authentication of Flammulina velutipes cultivare by using strain-specific sequence-characterized amplified region (SCAR) markers developed from inter-simple sequence repeat (ISSR) markers. The genomic DNA polymorphism was analyzed by the ISSR technique in 7 strains of F. velutipes presently cultivated in China on a commercial scale. Eight primers selected from 20 ISSR primers amplified 104 clear and stable bands, of which 81 bands were polymorphic. Among the selected primers, primer ISSR9 can distinguish strain No. 12 from the other 6 strains by amplifying a unique and reproducible band of approximately 750 bp. According to the sequence of the strain-specific fragment, a pair of SCAR primers was designed to diagnose strain No. 12 on the molecular level. The validity of the SCAR marker was confirmed by using DNA samples from another 12 strains of F. velutipes obtained from different parts of China. Our data provided the foundation for a precise and rapid PCR-based strain-diagnostic system for F. Velutipes.
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%.
An experiment was carried out to compare cadmium and copper absorption and mineral nutrition accumulation in pennisetum and tall fescue in order to select an appropriate grass to remediate Cd/Cu-contaminated soil and explore their detoxification mechanisms of contamination by mineral elements. The biomass remained constant in tall fescue under each Cd addition level and increased in pennisetum until Cu reached 500 μM, whereas they dramatically decreased as the Cu or Cd solution increased, which was concurrent with quadratic regression model analysis. The Cd/Cu concentrations in tall fescue were mostly accumulated in the roots and were much higher than those in pennisetum. The extracted amount of Cd in the shoots and the total Cu concentrations of pennisetum were higher than the corresponding values in tall fescue at every Cd/Cu addition level. Negative correlations were observed between Cd and shoot Ca, Cu, K, Mg, and Zn, and root Cu and Na of tall fescue and the root K of pennisetum. The Cu concentration was negatively correlated with K and positively correlated with Na in tall fescue and pennisetum under the Cu treatments. As the Cd/Cu concentration in solution increased, K/Na values were significantly decreased in the roots of tall fescue under Cu stress and pennisetum under Cd/Cu stress, whereas they increased in the roots of tall fescue under Cd addition. In summary, pennisetum exhibited the greater biomass and Cd/Cu extraction; indicating it as a candidate energy grass for phytoextraction. The adjustment capacity of grass for K and Na might relate to the tolerance to Cd/Cu.
By colchicine treatment of hybrids between Triticum turgidum and Aegilops tauschii (as seedlings), a fertile wheat plant (SHW-L2) carrying 56 chromosomes was artificially synthesized. At metaphase I of 50 pollen mother cells, the 56 chromosomes of the new wheat SHW-L2 showed a mean pairing configuration of 2.82 univalents, 6.18 rod bivalents, 19.39 ring bivalents, 0.5 trivalents, and 0.14 quadrivalents. Cytological analyses suggested that SHW-L2 had additional 7 pairs of chromosomes from the A and D genome besides the 42 chromosomes of common wheat. The special chromosome constitution of SHW-L2 may be derived from the chromosome doubling by the colchicine treatment of seedlings and then spontaneous doubling of gametes.
The expiration date of biopesticidal products is an essential feature of their use and storage. In the present work, the expiration date of biocontrol agent was predicted using the accelerated aging method. The available bacteria in Bacillus subtilis B579 biocontrol agent were 3.7 ± 0.2 × 10¹¹ CFU/g. It is calculated that the expiration date of the agent was about 17 months at 25°C. During this period, the available bacteria retained more than 90% of the value in the initial product. Thus, this work suggests the expiration date of biocontrol agents composed with spores could be estimated using the accelerated aging method.
Introduction. It is well known that exposure to organic dust can cause adverse respiratory effect. The pathogen-associated molecular patterns (PAMPS) in the organic dust, such as endotoxin from Gram-negative bacteria cell wall and fungal components, can trigger the release of cytokine (e.g. Interleukin 1β (IL-1β)) and chemokine (e.g. Interleukin 8 (IL-8)) from the immune cells in the airways. Objective. To evaluate the potential inflammatory effects of organic dust exposure in energy plants in Denmark. Materials and methods. Nasal lavage (NAL) and exhaled breath condensate (EBC) were sampled at Monday morning (referred to as before work) and again at Thursday afternoon (referred to as after work). NAL IL-8, EBC pH, IL-1β concentration were measured. Personal exposure to endotoxin and dust was calculated from time spent on different tasks and measured average work area exposures. Results. Before work, workers from biofuel plants had a higher IL-1β and IL-8 concentration compared to conventional fuel plants (control group). Specifically, the IL-1β level of moderately and most exposed group, and IL-8 level of the least exposed group were higher compared to the control group. The changes of IL-1β, pH and IL-8 during a work week were not significant. Workers with rhinitis had a lower percentage change of IL-8 compared to healthy workers. Conclusions. An increased level of EBC IL-1β in biofuel energy plant workers before work indicated a chronic or sub-chronic inflammation. The percentage change of IL-8 was lower in workers with rhinitis compared to healthy workers.
The purpose of the study was to define transient changes in the concentration of inflammatory biomarkers and cartilage biomarkers in the synovial fluid of joints following experimentally induced acute equine synovitis. Acute synovitis was induced in eight skeletal!) mature mares by a sterile intra-articular injection of 1 mL of phosphate-buffered saline (PBS) containing 0.5 ng of lipopolysaccharide (LPS). The solution was injected into the right middle carpal joint. One mL of sterile PBS was injected into the left control joint. Synovial fluid was obtained at the baseline level and at 8, 24, and 168 h after injection. The levels of inflammatory biomarkers-prostaglandin E2 (PGE2), interleukin 1ß (IL-1 ß), and tumour necrosis factor-α (TNF-α), and cartilage turnover biomarkers-collagenase-cleavage neoepitope of type II collagen (C2C) and C-terminal crosslinked telopeptide type II collagen (CTX-II) were detected with proper assays. Single injections of LPS raised the number of svnovial white blood cells and concentrations of total protein, PGE2, IL-Iß, TNF-α, C2C, and CTX-II. PGE2 and IL-1 ß rose sharply at 8 h, while TNF-α increased steadily through 8 h and 24 h, at that point; these three factors returned to the baseline level by 168 h. The time course of C2C and CTX-II concentrations peaked sharply at 24 h, and continued to be significant!) elevated over the baseline level even at 168 h. Injections of LPS into the joints led to a temporal inflammatory response, which in turn increased local release of inflammatory biomarkers and significantly altered the concentrations of cartilage markers in the synovial fluid.
The black locust (Robinia pseudoacacia L.) is an important tree species not only for the vegetation rehabilitation but also for the photosynthetic carbon dynamics on the Loess Plateau. Slope aspect and stand age play important roles in the photosynthesis of the black locusts. To investigate the photosynthetic carbon fixation capacity (PCFC) of the juvenile and mature black locusts located on the sunny and shady slopes, we have analyzed the capacity and daily dynamics of photosynthesis of the whole canopy of juvenile (6-year-old) and mature (18-year-old) black locusts located on the sunny (southeast facing) and shady (northwest facing) slopes. Mature plantations on the sunny slopes have lower average daily E, VPD, CE, An, LAI and PCFC than those on the shady slopes. Juvenile plantations have higher average daily gs, E, Ci/Ca, CE, An and PCFC compared to the mature plantations. It is concluded that the lower average daily An and PCFC of the mature black locust plantations on the sunny slopes may be due to variations in the microclimatic conditions between sunny and shady slope aspects. The higher average daily An and PCFC of the juvenile black locust plantations are likely associated with stand agerelated differences in tree sizes.
Zinc, as one of the essential microelements in crop plant, plays a crucial role in resistance to drought stress. To acquire a comprehensive of the physiological mechanism of resistance to drought stress enhanced by supplemental Zn in cotton, a hydroponic trial was conducted to investigate the changes in antioxidants and osmoregulation substances under zinc deficient and zinc sufficient conditions after 0, 3, 6 and 48 h of polyethylene glycol 6000-simulated drought stress. The present research showed that supplemental Zn significantly enhanced photosynthetic rate, chlorophyll a, chlorophyll b and dry matter of cotton under polyethylene glycol 6000 simulated drought stress, indicating that supplemental zinc improved the cotton growth. The antioxidant enzymes activities such as catalase, ascorbate peroxidase and superoxide dismutase, and non-enzymatic antioxidants such as carotenoid, reduced glutathione and ascorbic acid were all significantly enhanced and malonaldehyde content was remarkably reduced by supplemental zinc under polyethylene glycol 6000 simulated drought stress, indicating that the capacity of scavenging active oxygen species was improved by supplemental zinc in cotton. The osmoregulation substances such as soluble sugar, proline and soluble protein were all enhanced by supplemental zinc under Polyethylene glycol 6000 simulated drought stress, suggesting that zinc enhanced the osmotic adjustment capacity of cotton. It is implied that supplemental zinc could enhance the resistance to drought stress by inducing the buildup of antioxidative defences and osmotic adjustment ability in cotton.
Morphine induces adaptive changes in gene expression throughout the reward circuitry of brain. Recent research has proven the functional interactions between opioid and endogenous cannabinoid system in the central nervous system (CNS). The cannabinoid receptor 1 (CBj-R) is one of the receptors that mediate the actions of cannabinoids and endocannabinoids in the CNS. Here, we investigated the expression of CBrR in mRNA and protein levels in the brains of rats treated with acute and repeated morphine. Three groups of rats received intraperitoneal injections (ip injections) of saline, acute morphine (10 mg/ kg) and repeated morphine (10 mg/kg, twice daily for 12 consecutive days), and the mRNA levels and protein expressions of CB1-R were examined. RT-PCR and western blot analyses supported that both mRNA and protein levels of CB1-R in cortex, cerebellum and hippocampus were increased by repeated morphine treatment. However, the mRNA level in cerebellum was down-regulated only after acute morphine treatment and would returned to basal levels later. We used immunohistochemistry techniques to determine the functional expression of CB1-R in morphine treated rat's brain. Enzyme- Linked Immunosorbent Assay (ELISA) revealed the significant increase of cytokine (IL-ip, IL-6) levels in the repeated morphine treatment rats' cortex and hippocampus regions, which are both addiction-related brain areas. In addition, the results from RT-PCR and western blot assay indicated that the expression of CB1-R was directly increased by morphine treatment in vitro. All the results indicated that the CB1-R expression could be changed by morphine exposure and it might be involved in neural immune function, which provided a potential target for neurogenic disease treatment.
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