Antioxidant and antihemolytic activities of methanol extract of Hyssopus angustifolius

This study was designed to evaluate antioxidant and antihemolytic activities of Hyssopus angustifolius flower, stem and leaf methanol extracts by employing various in vitro assays. The leaf extract showed the best activity in DPPH (63.2 ± 2.3 μg mL-1) and H2O2  (55.6 ± 2.6 μg mL-1) models compared to the other extracts. However, flower extract exhibited the highest Fe2+ chelating activity (131.4 ± 4.4 μg mL-1). The extracts exhibited good antioxidant activity in linoleic acid peroxidation and reducing power assays, but were not comparable to vitamin C. The stem (23.58 ± 0.7 μg mL-1) and leaf (26.21 ± 1 μg mL-1) extracts showed highest level of antihemolytic activity than the flower extract

MIMO Underwater Visible Light Communications: Comprehensive Channel Study, Performance Analysis, and Multiple-Symbol Detection

In this paper, we analytically study the bit error rate (BER) performance of underwater visible light communication (UVLC) systems with binary pulse position modulation (BPPM). We simulate the channel fading-free impulse response (FFIR) based on Monte Carlo numerical method to take into account the absorption and scattering effects. Additionally, to characterize turbulence effects, we multiply the aforementioned FFIR by a fading coefficient which for weak oceanic turbulence can be modeled as a lognormal random variable (RV). Moreover, to mitigate turbulence effects, we employ multiple transmitters and/or receivers, i.e., spatial diversity technique over UVLC links. Closed-form expressions for the system BER are provided, when equal gain combiner (EGC) is employed at the receiver side, thanks to Gauss-Hermite quadrature formula and approximation to the sum of lognormal RVs. We further apply saddle-point approximation, an accurate photon-counting-based method, to evaluate the system BER in the presence of shot noise. Both laser-based collimated and light emitting diode (LED)-based diffusive links are investigated. Since multiple-scattering effect of UVLC channels on the propagating photons causes considerable inter-symbol interference (ISI), especially for diffusive channels, we also obtain the optimum multiple-symbol detection (MSD) algorithm to significantly alleviate ISI effects and improve the system performance. Our numerical analysis indicates good matches between the analytical and photon-counting results implying the negligibility of signal-dependent shot noise, and also between analytical results and numerical simulations confirming the accuracy of our derived closed-form expressions for the system BER. Besides, our results show that spatial diversity significantly mitigates fading impairments while MSD considerably alleviates ISI deteriorations

Nitric oxide radical scavenging potential of some Elburz medicinal plants

Some plants scavenge nitric oxide (NO) with high affinity. For this purpose, forty extracts from 26 medicinal plants, growing extensively in Elburz mountains, were evaluated for their NO scavenging activity. Total phenolic and flavonoid contents of these extracts were also measured by Folin Ciocalteu and AlCl3 colorimetric assays, respectively. Sambucus ebulus fruit aqueous extract and Pterocarya fraxinifolia leaf methanol extract showed better activity than others with IC50 equal to 29 and 65 g ml-1, respectively. NO is also implicated in inflammation and other pathological conditions, therefore very powerful scavenging activity of S. ebulus fruit extract may explain its very good anti-inflammatory activity. Phenolic and flavonoids contents of the extracts varied between 10.2 - 200.4 and 2.1 - 90.9 mg g-1 of extract, respectively. Good correlations could be found between total phenolic contents and NO scavenging activity through linear regression analysis (R2 = 0.63). There was also a better correlation between total flavonoids and NO scavenging activity (R2 = 0.73). High NO scavenging activity in plants can candidate them for testing their anti-inflammatory property.Key words: Antiinflammatory, flavonoid contents, medicinal plants, nitric oxide scavenging activity, phenolic contents, Sambucus ebulus, Pterocarya fraxinifolia

Identifying candidate drivers of drug response in heterogeneous cancer by mining high throughput genomics data

List of initial modulators for the resistant group. (TXT 1 kb

Performance of polymer-concrete composites in service life of maritime structures

University of Technology Sydney. Faculty of Engineering and Information Technology.Premature deterioration of Reinforced Concrete (RC) structures exposed to severe environment has become a global problem with serious economic consequences, environmental impact, and safety issues. According to the enormous investigations, it is evident that the dominant factor of this process is the chloride-induced corrosion of the steel reinforcement in RC structures. Diffusion of the chloride into the concrete occurs through the interconnected pores and surface cracks generated by different sources such as external loading and shrinkage. Large number of the wide cracks not only can accelerate the diffusion process but also enhance the probability of the steel corrosion leading to decreasing the service life of structures. In spite of many conducted studies, records and case studies confirm that the problem still exists. In this study, current significant corrosion preventing methods have been investigated and their advantages and disadvantages have been examined. Based on this investigation, modifying and improving the microstructure of the concrete, to reduce its permeability, gives the impression to be the most leading method due to easy implementation and lower cost. In the experimental program of this research two main research areas consisting (i) effect of polymer-concrete composites on mechanical properties of the concrete, and (ii) effect of polymer-concrete composites on service life of RC structures exposed to severe environmental exposure conditions have been investigated. In addition, two different categories of polymer-concrete composites including synthetic fibres and latex polymer have been selected to investigate their effects on mechanical properties and durability performance of the composites. According to the result of this study, polymer-concrete composites reveal enhancement on the mechanical properties of the concrete such as compressive strength, flexural strength, and tensile strength. Furthermore, to assess the durability performance of the polymer-concrete composites series of long-term tests (up to 720 days) have been conducted in the concrete laboratory of University of Technology Sydney. In this research, service life of the RC structure has been taken either as time of corrosion initiation (corrosion free service life) or time of cracking of the concrete cover due to steel corrosion (corrosion time). Chloride content measurement was utilized in this study to find the chloride diffusion rate in polymer-concrete composites exposed to high concentrated chloride solution for 24 months. Results of chloride content tests revealed that the polymer-concrete composites can significantly reduce the chloride diffusion rate in concrete and extend the corrosion-free service life of RC structures. To estimate the corresponding service life to corrosion time, an accelerated electrochemical method was deployed in order to obtain the results in relatively shorter time. The results of corrosion time also confirmed that the polymer-concrete composites can increase the service life of the structure considerably. Most of the previously proposed models available in the literature, consider the chloride diffusion coefficient as a constant parameter. In this study, a new mathematical model was proposed to determine the chloride diffusion coefficient as a time-dependent parameter. In the proposed model the effects of water cement ratio, cement type, cement content, and coarse aggregate proportion were investigated and included Finally, finite element analysis by Utilizing ABAQUS has been performed to verify the mathematical model. The results of the computer modeling and long-term experimental program are in reasonably good agreement

Constructing the ‘citizen’ in citizenship education

In the field of education, the discourses of ‘citizenship education’ aremore than at any other period of Canadian historycentre stage. As public schooling strives to offer citizenship education amenable to the needs of varied identities, the ideological premises, concepts, and goals of citizenship education must be interrogated. Critically synthesizing the developments of citizenship education since the Multiculturalism Policy of 1971, the gaps in citizenship education will be explored by discussing policy and pedagogical approaches. This article will conclude by offering pedagogical and conceptual alternatives to citizenship education, which can serve to address the outlined gaps in learning for citizenship for diverse learners

Comparative study of metasearch engines performance in retrieving Library and information Science documents on the web

Internet searching tools, Search engines and Metasearch engines are among. Metasearch engines do not have their own databases. They send user’s queries simultaneously to multiple web Search engines and/or web Directories. Some of researchers and compaines that conduct the Metasearch engines, believe that these tools retrieve more relevant hits. This research was conducted to determine this idea in searching and retrieving Library and information science documents. 12 major Metaseach engins that introduced in www.searchengine watch.com at September 11, 2000 were selected. On the other hand, keywords of articles titles which selected were published in library and information science periodicals during one year (1378 = march 21, 1999 – march 20, 2000). Keywords were classified acording to LISA classification of library and information science subjects. Then, these keywords were searched in 12 Metasearch engines. The 10 first records were considered to be evaluated. The results showed that inspite of using the best Metaseach engines, Just approximately %30 of sources are relevant. Also results indicate that C4 Metasearch engine in comparison with others, retrieves more sources in various subjects, but more relevant sources retrieve form C/ Net Metasearch engine