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71.
In this research, nickel oxide (NiO) transparent semiconducting films are prepared by spray pyrolysis technique on glass substrates. The effect of Ni concentration in initial solution and substrate temperature on the structural, electrical, thermoelectrical, optical and photoconductivity properties of NiO thin films are studied. The results of investigations show that optimum Ni concentration and suitable substrate temperature for preparation of basic undoped NiO thin films with p-type conductivity and high optical transparency is 0.1 M and 450 °C, respectively. Then, by using these optimized deposition parameters, nickel-lithium oxide ((Li:Ni)Ox) alloy films are prepared. The XRD structural analysis indicate the formation of the cubic structure of NiO and (Li:Ni)Ox alloy films. Also, in high Li doping levels, Ni2O3 and NiCl2 phases are observed. The electrical measurements show that the resistance of the films decreases with increasing Li level up to 50 at%. For these films, the optical band gap and carrier concentration are obtained to be 3.6 eV and 1015-1018 cm−3, respectively.  相似文献   
72.
This paper is concerned with the minimisation of the update response time in distributed database systems (DDBS) where resequencing algorithms are used to preserve the consistency of the databases. The authors proposed a novel resequencing technique, in reference [7], namely hop-by-hop resequencing with batch processing for connecting the first stage to the second stage of a two-stage DDBS. In this paper, a stochastic upper bound is calculated for the system response time and it is shown that the system response is smaller than that for a one-stage system of the same size and parameters.  相似文献   
73.
The main objective of the present study was to evaluate the release of aroma compounds from a banana soft drink complex model system in comparison with their release from simple model systems, each contains individual food ingredients. The effect of different food ingredients (sweeteners and thickeners at different concentrations), used in formulation of the soft drinks, on flavor release from simple model systems containing banana flavor was evaluated separately. The optimum release of isoamyl acetate (the most potent odorant of banana aroma) was observed at a concentration of 10% of each investigated sweetener (sucrose, glucose, and corn syrup). Pectin and xanthane showed the highest release at a concentration of 2.5 and 0.8% w/w, respectively. The level of each ingredient that showed the optimum release of isoamyl acetate was selected and used in formulation of a banana soft drink complex model system. The released volatiles were trapped by tenax and activated carbon. The gas chromatographic-mass spectrometric analysis revealed a gradual decrease (p < 0.05) in the volatile compounds release from the complex banana soft drink model system during storage for 90 days. However, the total content of the volatiles adsorbed by activated carbon trap was higher than that trapped by tenax. The percentage of isoamyl acetate to total volatiles (isoamyl acetate/total volatiles %) was calculated for each sample during storage. A distinct linear correlation was found between the calculated values and storage time (r = 0.97 and 0.92 for volatiles trapped by tenax and activated carbon, respectively). Sample stored for 60 days showed the highest value. These findings confirmed the results of aroma sensory evaluation.  相似文献   
74.
In this study, antioxidant and antihemolytic activities of ethanolic extract of flowers, leaves, and stems of Hyssopus officinalis L. Var. angustifolius were investigated employing different in vitro assay systems. Extracts showed good antioxidant activity. IC50 for 1,1-diphenyl-2-picryl hydrazyl radical-scavenging activity were 148.8 ± 4.31 μg mL?1 for flowers, 79.9 ± 2.63 μg mL?1 for stems, and 208.2 ± 6.45 μg mL?1 for leaves. All extracts showed moderate iron (II) chelating ability. Extracts exhibited good antioxidant activity in the hemoglobin-induced linoleic acid model and also they were capable of scavenging hydrogen peroxide in a concentration dependent manner. Extracts showed good antihemolytic activity againts hydrogen peroxide-induced hemolysis (IC50 were 48.51 ± 2.27 μg mL?1 for flowers, 19.47 ± 0.73 μg mL?1 for leaves, and 63.1 ± 2.65 μg mL?1 for stems). The total amount of phenolic compounds in the extracts was determined as gallic acid equivalents and total flavonoid content was calculated as quercetin equivalents from a calibration curve.  相似文献   
75.
76.
In recent decades,magnetic iron nanoparticles (NPs) have attracted much attention due to properties such as superparamagnetism,high surface area,large surface-to-volume ratio,and easy separation under external magnetic fields.Therefore,magnetic iron oxides have potential for use in numerous applications,including magnetic resonance imaging contrast enhancement,tissue repair,immunoassay,detoxification of biological fluids,drug delivery,hyperthermia,and cell separation.This review provides an updated and integrated focus on the fabrication and characterization of suitable magnetic iron NPs for biotechnological applications.The possible perspective and some challenges in the further development of these NPs are also discussed.  相似文献   
77.
Background: Tissue sources of pain emanating from degenerative discs remains incompletely understood. Canine intervertebral discs (IVDs) were needle puncture injured, 4-weeks later injected with either phosphate-buffered saline (PBS) or NTG-101, harvested after an additional fourteen weeks and then histologically evaluated for the expression of NGFr, BDNF, TrkB and CALCRL proteins. Quantification was performed using the HALO automated cell-counting scoring platform. Immunohistochemical analysis was also performed on human IVD tissue samples obtained from spinal surgery. Immunohistochemical analysis and quantification of neurotrophins and neuropeptides was performed using an in vivo canine model of degenerative disc disease and human degenerative disc tissue sections. Discs injected with NTG-101 showed significantly lower levels of Nerve Growth Factor receptor (NGFr/TrkA, p = 0.0001), BDNF (p = 0.009), TrkB (p = 0.002) and CALCRL (p = 0.008) relative to PBS injections. Human IVD tissue obtained from spinal surgery due to painful DDD show robust expression of NGFr, BDNF, TrkB and CALCRL proteins. A single intradiscal injection of NTG-101 significantly inhibits the expression of NGFr, BDNF, TrkB and CALCRL proteins in degenerative canine IVDs. These results strongly suggest that NTG-101 inhibits the development of neurotrophins that are strongly associated with painful degenerative disc disease and may have profound effects upon the management of patients living with discogenic pain.  相似文献   
78.
Hydrogen-specific policies are required to accelerate the adoption of low-carbon hydrogen. In this study, a range of economic instruments and regulations were incorporated explicitly to optimize a hydrogen supply chain. The effectivenes of policies aiming to enhance the financial viability of low-carbon hydrogen production was quantified. A spatially explicit, multi-period cost optimization model was developed for light duty hydrogen hydrogen vehicle deployment in British Columbia under three demand scenarios. Subsidies and regulations were coupled to current provincial policies (a carbon tax and a low carbon fuel standard). The results indicated that production tax credits and electricity incentives were up to 24 times more effective in facilitating low-carbon hydrogen production compared to capital subsidies, bans on steam methane reforming or the adoption of higher carbon taxes. The strategic deployment of policies over time was found to be more effective than cumulative subsidies.  相似文献   
79.
80.
Cell–cell communication is an essential mechanism for the maintenance and development of various organs, including the female reproductive system. Today, it is well-known that the function of the female reproductive system and successful pregnancy are related to appropriate follicular growth, oogenesis, implantation, embryo development, and proper fertilization, dependent on the main regulators of cellular crosstalk, exosomes. During exosome synthesis, selective packaging of different factors into these vesicles happens within the originating cells. Therefore, exosomes contain both genetic and proteomic data that could be applied as biomarkers or therapeutic targets in pregnancy-associated disorders or placental functions. In this context, the present review aims to compile information about the potential exosomes with key molecular cargos that are dysregulated in female reproductive diseases which lead to infertility, including polycystic ovary syndrome (PCOS), premature ovarian failure (POF), Asherman syndrome, endometriosis, endometrial cancer, cervical cancer, ovarian cancer, and preeclampsia, as well as signaling pathways related to the regulation of the reproductive system and pregnancy outcome during these pathological conditions. This review might help us realize the etiology of reproductive dysfunction and improve the early diagnosis and treatment of the related complications.  相似文献   
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