Antifungal activity of the extract of a macroalgae, gracilariopsis persica, against four plant pathogenic fungi

Nowadays, the extract of seaweeds has drawn attention as a rich source of bioactive me-tabolites. Seaweeds are known for their biologically active compounds whose antibacterial and an-tifungal activities have been documented. This research aimed to study the profile of phenolic compounds using the HPLC method and determine biologically active compounds using the GC‐MS method and the antifungal activity of Gracilariopsis persica against plant pathogenic fungi. G. persica was collected from its natural habitat in Suru of Bandar Abbas, Iran, dried, and extracted by meth-anol. The quantitative results on phenolic compounds using the HPLC method showed that the most abundant compounds in G. persica were rosmarinic acid (20.9 ± 0.41 mg/kg DW) and quercetin (11.21 ± 0.20 mg/kg DW), and the least abundant was cinnamic acid (1.4 ± 0.10 mg/kg DW). The GC‐ MS chromatography revealed 50 peaks in the methanolic extract of G. persica, implying 50 com-pounds. The most abundant components included cholest‐5‐en‐3‐ol (3 beta) (27.64%), palmitic acid (17.11%), heptadecane (7.71%), and palmitic acid methyl ester (6.66%). The antifungal activity of different concentrations of the extract was determined in vitro. The results as to the effect of the alga extract at the rates of 200, 400, 600, 800, and 1000 μL on the mycelial growth of four important plant pathogenic fungi, including Botrytis cinerea, Aspergillus niger, Penicillium expansum, and Pyricularia oryzae, revealed that the mycelial growth of all four fungi was lower at higher concentrations of the alga extract. However, the extract concentration of 1000 μL completely inhibited their mycelial growth. The antifungal activity of this alga may be related to the phenolic compounds, e.g., rosma-rinic acid and quercetin, as well as compounds such as palmitic acid, oleic acid, and other components identified using the GC‐MS method whose antifungal effects have already been confirmed

RF modulator design for a low level pilot sub-system

peer reviewedThis paper presents an adaptive duplexer using cancelling instead of filtering to obtain sufficient transmitter (Tx) leakage and noise isolation in the receiver. A low level pseudo-noise (PN) pilot signal is introduced in order to adjust the cancelling coefficients. To modulate the pilot signal to radio frequencies a straightforward direct up-conversion mixer with low carrier feedthrough has been designed. This structure has been implemented in the silicon-on-sapphire (SOS) 250 nm GC process. © 2014 IEEE

Efectiveness of fungal bacterial biofertilizers on agrobiochemical attributes of quinoa (Chenopodium quinoa willd.) under salinity stress

The efects of fungi and bacteria biofertilizers under salinity stress were studied on some morphological and physiological traits of quinoa. The experiment was conducted as a factorial based on a completely randomized design with three replications. The factors included NaCl (no salinity-150 mM NaCl and 300 mM NaCl), Trichoderma (no Trichoderma and Trichoderma), and bacterial biofertilizers (no biofertilizer-N biofertilizer and P biofertilizer). The highest shoot and root length and dry weight were observed in the treatment of no salinity+no Trichoderma+N biofertilizer. Salinity increased Na+and K+content and decreased K+/Na+ratio, whereas the application of Trichoderma alleviated the efect of salinity on these factors. Ca2+/Na+ and Mg2+/Na+ ratios were signifcantly decreased in high salinity level compared to the zero salinity level. The highest and lowest phenol content was observed in the treatments of 300 mM NaCl+Trichoderma+P biofertilizer and no salinity+no Trichoderma+N biofertilizer, respectively. Flavonoid content was higher in the treatments of no salinity+Trichoderma+N biofertilizer and no salinity+Trichoderma+P biofertilizer than in the other treatments, also The high-performance liquid chromatography analysis revealed that all phenolic and favonoid compounds exhibited the greatest increase in treatments of no salinity+Trichoderma+N biofertilizer and no salinity+Trichoderma+P biofertilizer, which is consistent with the signifcant increase in total favonoid content in these treatments. The results showed that using N biofertilizer can improve the growth and development of quinoa in saline soils

Active duplexing for software defined radio

peer reviewedPassive filters are implemented via advanced technologies in the form of surface acoustic wave (SAW) and thin film bulk acoustic resonator (FBAR) devices. These not only exhibit low noise and high linearity features, but also have fixed centre frequency and bandwidth, making them inflexible. Adaptive duplexing eliminates the need for switched multiple band reject filters (BRF) by using a cancellation process. The proposed state of the art technique has the potential to reduce the cost and size of the RF frontend. The operation of the system is described and key specifications of the major building blocks are developed. Test bed measurements illustrate the practical implementation of this methodology. © 2014 IEEE