ABSTRACT
The genus Neocinnamomum is considered to be one of the most enigmatic groups in Lauraceae, mainly distributed in tropical and subtropical regions of Southeast Asia. The genus contains valuable oilseed and medicinal tree species. However, there are few studies on the genus Neocinnamomum at present, and its interspecific relationship is still unclear. In order to explore the genetic structure and evolutionary characteristics of the Neocinnamomum chloroplast genome and to resolve the species relationships within the genus, comparative genomic and phylogenetic analyses were performed on the whole chloroplast genome sequences of 51 samples representing seven Neocinnamomum taxa. The whole Neocinnamomum chloroplast genome size ranged from 150,753-150,956 bp, with a GC content of 38.8%-38.9%. A total of 128 genes were annotated within the Neocinnamomum chloroplast genome, including 84 protein coding genes, 8 rRNA genes, and 36 tRNA genes. Between 71-82 SSRs were detected, among which A/T base repeats were the most common. The chloroplast genome contained a total of 31 preferred codons. Three highly variable regions, trnN-GUU-ndhF, petA-psbJ, and ccsA-ndhD, were identified with Pi values > 0.004. Based on the whole chloroplast genome phylogenetic tree, the phylogenetic relationships among the seven Neocinnamomum taxa were determined. N. delavayi and N. fargesii were the most closely related species, and N. lecomtei was identified as the most basal taxon. In this study, the characteristics and sequence variation of the chloroplast genomes of seven Neocinnamomum taxa were revealed, and the genetic relationship among the species was clarified. The results of this study will provide a reference for subsequent molecular marker development and phylogenetic research of Neocinnamomum.
ABSTRACT
A very compact microstrip reconfigurable filter for fourth-generation (4G) and sub-6 GHz fifth-generation (5G) systems using a new hybrid co-simulation method is presented in this manuscript. The basic microstrip design uses three coupled line resonators with λ/4 open-circuited stubs. The coupling coefficients between the adjacent and non-adjacent resonators are used to tune the filter at the required center frequency to cover the frequency range from 2.5 to 3.8 GHz. The coupling coefficient factors between the adjacent resonators are adjusted to control and achieve the required bandwidth, while the input and output external quality factors are adjusted to ensure maximum power transfer between the input and output ports. Two varactor diodes and biasing circuit components are selected and designed to meet the targeted performance for the tunable filter. The impedance bandwidth is maintained between 95 and 115 MHz with measured return losses of more than 17 dB and measured insertion loss of less than 1 dB. Computer simulation technology (CST) is utilized to design and optimize the presented reconfigurable filter, with hybrid co-simulation technique, using both CST microwave studio (MWS) and CST design studio (DS), is applied to build the model by considering the SPICE representation for the varactor switches and all electronic elements of the biasing circuit. The introduced reconfigurable microstrip filter is also fabricated using a Rogers RO3010 material with a relative dielectric constant of 10.1 and it is printed on a very compact size of 13 × 8 × 0.81 mm3. An excellent agreement is obtained between the simulation and measurement performance.
