Low Profile MIMO Diversity Antenna with Multiple Feed

ABSTRACT A Compact low profile MIMO Diversity antenna system with multiple feeds with a size of 105mm*61.5mm is proposed. Multiple feeds are used to provide maximum power to antenna elements so that signal can propagate a long distance. The proposed antenna is achieving multiple frequencies, i.e. 2.5 GHz, 3.21 GHz, 4.22GHz, 4.68GHz, 6.5GHz, 6.74 GHz, 7 GHz and 8.35 GHz. Measured S-parameters show the isolation is -23.715 db. The maximum achievable bandwidth is 1.32 GHz (1320 MHz). This antenna can be applicable at Wimax, WLAN, LTE and Satellite Bands

Functional characterization of the oxaloacetase encoding gene and elimination of oxalate formation in the β-lactam producer Penicillium chrysogenum

Penicillium chrysogenum is widely used as an industrial antibiotic producer, in particular in the synthesis of β-lactam antibiotics such as penicillins and cephalosporins. In industrial processes, oxalic acid formation leads to reduced product yields. Moreover, precipitation of calcium oxalate complicates product recovery. We observed oxalate production in glucose-limited chemostat cultures of P. chrysogenum grown with or without addition of adipic acid, side-chain of the cephalosporin precursor adipoyl-6-aminopenicillinic acid (ad-6-APA). Oxalate accounted for up to 5% of the consumed carbon source. In filamentous fungi, oxaloacetate hydrolase (OAH; EC3.7.1.1) is generally responsible for oxalate production. The P. chrysogenum genome harbours four orthologs of the A. niger oahA gene. Chemostat-based transcriptome analyses revealed a significant correlation between extracellular oxalate titers and expression level of the genes Pc18g05100 and Pc22g24830. To assess their possible involvement in oxalate production, both genes were cloned in Saccharomyces cerevisiae, yeast that does not produce oxalate. Only the expression of Pc22g24830 led to production of oxalic acid in S. cerevisiae. Subsequent deletion of Pc22g28430 in P. chrysogenum led to complete elimination of oxalate production, whilst improving yields of the cephalosporin precursor ad-6-APA.