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61.
Copper oxide (CuO) nanoparticles (NPs) synthesized through co-precipitation method were employed in MS media during in vitro culture of Stevia rebaudiana. Physiological characteristics, production of steviol glycosides, and antioxidative parameters were investigated in regenerated plants. CuO NPs had crystalline monoclinic cubic cuprous oxides with average size 47 nm. The NPs were applied at 0, 0.1, 1.0, 10, 100 and 1000 mg/L in MS media for direct organogenesis of S. rebaudiana from nodal segments. Shoot organogenesis was found highest (88.5%) at 10 mg/L CuO and average shoot length, mean number of shoot per explant, and fresh weight were also found significantly higher at the same concentration. High performance liquid chromatography (HPLC) illustrated significant rise of bioactive major steviol glycosides (rebaudioside A and stevioside) at 10 mg/L CuO NPs in MS media. The oxidative stress produced by CuO nanoparticles on S. rebaudiana was affirmed by antioxidant activities i.e. total antioxidant activity (TAC), total reducing power (TRP) and 2,2-diphenyl-1-picryl hydrazyl (DPPH)-free radical scavenging activity. The oxidative stress generated by NPs involved production of antioxidative molecules total phenolic content (TPC), total flavonoid content (TFC) depending on NPs concentration. The study concludes that copper oxide nanoparticles functions as a stimulator of bioactive components productions, and can be employed in in vitro batch cultures.  相似文献   
62.
The most significant groupings of cold-blooded creatures are the fish family. It is crucial to recognize and categorize the most significant species of fish since various species of seafood diseases and decay exhibit different symptoms. Systems based on enhanced deep learning can replace the area's currently cumbersome and sluggish traditional approaches. Although it seems straightforward, classifying fish images is a complex procedure. In addition, the scientific study of population distribution and geographic patterns is important for advancing the field's present advancements. The goal of the proposed work is to identify the best performing strategy using cutting-edge computer vision, the Chaotic Oppositional Based Whale Optimization Algorithm (CO-WOA), and data mining techniques. Performance comparisons with leading models, such as Convolutional Neural Networks (CNN) and VGG-19, are made to confirm the applicability of the suggested method. The suggested feature extraction approach with Proposed Deep Learning Model was used in the research, yielding accuracy rates of 100 %. The performance was also compared to cutting-edge image processing models with an accuracy of 98.48 %, 98.58 %, 99.04 %, 98.44 %, 99.18 % and 99.63 % such as Convolutional Neural Networks, ResNet150V2, DenseNet, Visual Geometry Group-19, Inception V3, Xception. Using an empirical method leveraging artificial neural networks, the Proposed Deep Learning model was shown to be the best model.  相似文献   
63.

Petunia × hybrida Vilm. is a fast-growing ornamental plant that was cultured under varying storage conditions to address seasonal fluctuations in microcutting demand. The effects of storage period (16 to 32 wk), temperature (15 to 23°C), low and high light intensity, sucrose (1 to 5% w/v), and mannitol (0 to 4% w/v) in factorial arrangements were analyzed. Stored and non-stored shoots were compared for microcutting production, harvested twice at 3-wk intervals, and were subsequently transferred to the greenhouse for 17 d. Nearly all plants from 16-wk storage survived well at all treatment conditions and the quality and quantity of microcuttings were enhanced from shoots stored at 15°C and 3% (w/v) sucrose, without mannitol for all storage periods. Another experiment tested 11- to 25-wk storage period with Petunia hybrida ‘Ragtime’ and ‘Suncatcher’ at 12°C and low light intensity. Repeated cycles of microcutting at 2-wk intervals were extended with ex vitro rooting in the greenhouse for 15 d. More and better quality microcuttings were obtained from the second and third cutting cycles than from the first or fourth cycles. By reducing temperature and light intensity, Petunia hybrida was successfully stored for 32 wk (without mannitol). A seasonal schedule with a short production window, followed by cutting large numbers of high-quality shoot-tips, could be affected and efficiently managed through storage. The value of stored shoots was enhanced by extending the number of times a shoot could be cut over repeated cutting cycles with a gain in microcutting quality.

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64.
Current investigation has for the first time utilized Trichocomaceae fungi i.e. Aspergillus niger, Aspergillus terreus, Aspergillus flavus and Pencillium i.e. Penicillium chrysogenum for augmenting the phytoremediation potential of bioenergy crops wheat (Zea mays) and ? sunflower (Helianthus annuus). Phytoremediation was done for mitigation of heavy metals i.e. Chromium (Cr), Copper (Cu), Lead (Pb) and Cadmium (Cd) from contaminated soils of agricultural significance. Phytoremediant crops were inoculated with fungal cultures by three methods i.e. mixing method, seed inoculation method and layering spreading method. Maize and sunflower plants after fungal inoculation were harvested after 60 days of germination. The estimation of % biomass and bioenergy of maize and sunflower plants was done. Results were indicative of the good phytoremediation potential of roots and shoots for uptake of heavy metals i.e. CrAspergillus niger, Aspergillus terreus and Aspergillus flavus by fungal inoculation methods. Sunflower and fungal inoculum of Aspergillus flavus and Penicillium chrysogenum extracted significant quantity of metals from the soil. By three fungal inoculation methods, range of % production of biomass was 84?87% and sunflower plants dry biomass 9.6 g yielded 0.16% of oil. Obtained results are have favored the use of fungal inoculation as an effective mode for phytoremediation augmentation of maize and sunflower. Furthermore, current work also signifies the sustainable conversion of bioenergy crops to biofuel production in a cost effective mode.  相似文献   
65.
The present paper represents the ethnopharmacological survey of Sudhan Gali, Kashmir, Pakistan. The study revealed that 12 plant species belonging to 11 families were used for the treatment of stomach, diabetes and ophthalmic diseases by the local people in Sudhan Gali. Achillea millefolium , Aconitum heterophyllum, Berberis lycium, Polygonum amplexicaule, Mentha longifolia, Paeonia emodi, Plantago lanceolata were locally used for stomach related problems treatment; Berberis lycium, Skimmia lareola, Solanum dulcamara for diabetes and Geranium wallichianum, Artemisia vulgaris, Solanum dulcamara, and Corydalis crassifolia used for the treatment of ophthalmic diseases. Two species Berberis lycium and Solanum dulcamara have multipurpose value. Former is used to treat stomach as well as diabetes while latter is used to treat not only to diabetes but also ophthalmic diseases. According to IUCN categories , out of these 12 plant species collected and marketed, Polygonum amplexicaule and Paeonia emodi are endangered, Aconitum heterophyllum; Berberis lycium species are vulnerable while Plantago lanceolata and Skimmia lareola species are rare.The availability of these medicinal plants has decreased during the past 20 years and these are facing a drastic biotic pressure due to their extensive usage and non-scientific methods of collection. It is quite evident that these valuable native medicinal plants species are going to decline in number and ultimately will become extinct if no timely proper conservation strategies are adopted.  相似文献   
66.
The glycosaminoglycan heparan sulfate (HS), present at the surface of most cells and ubiquitous in extracellular matrix, binds many soluble extracellular signalling molecules such as chemokines and growth factors, and regulates their transport and effector functions. It is, however, unknown whether upon binding HS these proteins can affect the long-range structure of HS. To test this idea, we interrogated a supramolecular model system, in which HS chains grafted to streptavidin-functionalized oligoethylene glycol monolayers or supported lipid bilayers mimic the HS-rich pericellular or extracellular matrix, with the biophysical techniques quartz crystal microbalance (QCM-D) and fluorescence recovery after photobleaching (FRAP). We were able to control and characterize the supramolecular presentation of HS chains—their local density, orientation, conformation and lateral mobility—and their interaction with proteins. The chemokine CXCL12α (or SDF-1α) rigidified the HS film, and this effect was due to protein-mediated cross-linking of HS chains. Complementary measurements with CXCL12α mutants and the CXCL12γ isoform provided insight into the molecular mechanism underlying cross-linking. Fibroblast growth factor 2 (FGF-2), which has three HS binding sites, was also found to cross-link HS, but FGF-9, which has just one binding site, did not. Based on these data, we propose that the ability to cross-link HS is a generic feature of many cytokines and growth factors, which depends on the architecture of their HS binding sites. The ability to change matrix organization and physico-chemical properties (e.g. permeability and rigidification) implies that the functions of cytokines and growth factors may not simply be confined to the activation of cognate cellular receptors.  相似文献   
67.
Talat N  Shahid F  Perry S  Dawood G  Hussain R 《Cytokine》2011,54(2):136-143
Differential T cell trafficking through the blood compartment towards infected foci may be occurring in different stages of tuberculosis disease and infection. The aim of the present study was to identify cytokine signatures in the blood compartment in tuberculosis patients with pulmonary disease (PTB=19), recently exposed household contacts (HC=27) and nonexposed community controls (EC=37). Diluted (1:10) whole blood was cultured for 2 days and cytokine secretion was assessed using Cytometric Bead Array (Th1/Th2 kit II; BD Biosciences) which included IL-2, TNF-α, IFN-γ (Type1/T1), IL-4, IL-6 and IL-10 (Type2/T2). All T1/T2 cytokines were elevated in PTB (AUROC>0.9) while HC showed selective elevation of IL-6 (AUROC>0.7) compared to EC. Principal component analysis (PCA) extracted two groupings with Eigen values >1; IL-6 separated into the second component for PTB, HC and EC. After rotation, IFN-γ was correlated with the first component for PTB and EC and the second component for HC indicating an absence of T1/T2 dichotomy. Therefore endogenous cytokine signatures may indicate differential T cell trafficking in different stages of tuberculosis infection and disease.  相似文献   
68.
Humoral immune parameters like total immunoglobulins and specific antibody levels in serum were studied in filarial chyluria patients. Mean serum IgG was significantly reduced in this group compared to normal controls, while IgA and IgM levels remained comparable to controls. Anti-filarial antibody titre as measured by enzyme-linked immunosorbent assay also was significantly reduced. However, the total and specific IgE antibody titre was similar to that of controls. Specific IgE contents of the patients’ sera could be related to their microfilaraemic status.  相似文献   
69.
70.
Elevated levels of insecticides detoxifying enzymes, such as esterases, glutathione S‐transferases (GSTs), and cytochrome P‐450 monooxygenases, act in the resistance mechanisms in insects. In the present study, levels of these enzymes in the insecticide‐resistant ground spider Pardosa sumatrana (Thorell, 1890) were compared with a susceptible population (control) of the same species. Standard protocols were used for biochemical estimation of enzymes. The results showed significantly higher levels of nonspecific esterases and monooxygenases in resistant spiders compared to controls. The activity of GSTs was lower in the resistant spiders. Elevated levels of nonspecific esterases and monooxygenases suggest their role in metabolic resistance in P. sumatrana. The reduced levels of total protein contents revealed its possible consumption to meet energy demands.  相似文献   
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