Single nucleotide polymorphism and phylogenetic analysis of the exon 2 of leptin gene in Lohi sheep

Background: Leptin hormone, encoded by leptin (LEP) gene is involved in many biological and physiological processes in the body. Polymorphism in LEP gene has been observed and correlated with a variety of reproductive and productive traits in several sheep breeds worldwide, but its role has not been much studied in local sheep breeds of Pakistan. The present study was conducted to analyze polymorphism in LEP gene in Lohi breed of sheep.Methods: Subsequent to statistical analysis (generalized linear model), 18 animals were selected randomly from the flock for blood samples collection followed by DNA extraction, amplification using PCR prior to sequencing. The amplified product of exon 2 and partial intron 2 regions of LEP gene was 268bp.Results: Molecular analysis showed a heterozygous condition i.e. C>Y at position 15 and 18 in exon 2. The data on average daily weight gain (ADG) from birthday to 90 days were used for association study, while environmental effects were minimized by means of generalized linear model. Association of polymorphisms in LEP gene with ADG did not yield any significant results.Conclusion: In conclusion, analysis of LEP gene sequence verified the existence of genetic changes in Lohi sheep. Further investigations are needed to find variations that might be linked with traits of economic importance for upcoming breeding program sand marker-assisted selection.Keywords: DNA; Exon 2; LEP; PCR; Loh

A wideband circularly-polarized spiral antenna for CubeSat application

In this paper, a wideband circularly-polarized spiral antenna is proposed to be used for CubeSat application. The antenna covers two of CubeSat frequencies; the S-band (2.2 GHz) and X-band (8 GHz). The proposed antenna belongs to the wideband and frequency-independent antenna category, which are known to provide a constant radiation pattern, impedance and polarization throughout the whole bandwidth. The performance of the spiral is compared in two different conditions; in free space and above a ground plane with a separation distance of λ/4 at the operating frequency of 2.2 GHz and 8 GHz. The spiral above the ground plane exhibits a unidirectional radiation and higher gain with an increase of 26.6% (2.2 GHz) to 34.6% (8 GHz) than the free space spiral. Moreover, the return loss also managed to stay within the ideal limit of S11<-10dB (-19.528 dB at 2.2 GHz, and -21.92 dB at 8 GHz) and exhibits circularly-polarized radiation with low axial ratio < 3 dB (0.78 dB at 2.2 GHz, and 0.89 dB at 8 GHz)

Surfactant Incorporated Co Nanoparticles Polymer Composites with Uniform Dispersion and Double Percolation

Series of Cobalt nanoparticles incorporated polymethylmethacrylate composites in the presence and absence of dodecyl-benzene-sulphonic acid (DBSA-CoNPs/PMMA and CoNPs/PMMA, resp.) were synthesized by solution mixing methodology. UV-visible and FTIR techniques were used to confirm the formation of nanocomposite. UV-visible spectra of the composites showed the incorporation of filler particles in the polymer matrix. On the other hand, FTIR spectra indicated the physical interaction between the two phases of the composite. Moreover, the electrical nature of the composites was studied by plotting graphs between electrical conductivity (measured using LCR meter at 100 kHz) and contents of the filler particles as introduced in the polymer matrix. An increase in electrical conductivity was first observed with increasing filler concentration up to the critical percolation threshold value (0.5% for DBSA-CoNPs/PMMA and 1% for CoNPs/PMMA), which then dropped upon further increments in the filler content. However, at higher concentrations, a second jump in the conductivity was observed in case of DBSA-CoNPs/PMMA composites

A review of group B streptococcus (Gbs) vaginal colonization and ascending intrauterine infection: interaction between host immune responses and gbs virulence factors

Vaginal colonization with Group B streptococcus (GBS) or Streptococcus agalactiae can potentially cause ascending intrauterine infection among pregnant women, and hence it is known as one of the risk factors for preterm delivery. Ascending intrauterine infection may also cause the transmission of GBS to the fetus in utero and the newborn during delivery, leading to the development of early onset of neonatal infection. GBS are βhemolytic, gram-positive bacteria that are opportunistic commensal of the gastrointestinal and urogenital tract of approximately 18% of pregnant women globally. Intrapartum antibiotic prophylaxis (IAP) only reduces the rate of early onset neonatal infection, but not the late onset neonatal infection. Thus, the development of GBS vaccine is thought to be important to decrease the rate of preterm delivery and neonatal infections particularly in low-and-middle income countries where IAP program is not feasible. Vaccination can also be cost-effective for the healthcare system when executed together with IAP program. The aim of the current review is to summarize the mechanisms on how the GBS virulence factors interact with host immune components in the gestational tissues, leading to cervicovaginal colonization and ascending intrauterine infection. The elucidation of these mechanisms is essential for expediting the development of vaccines and novel therapeutic measures targeting these GBS virulence factors that will hamper the vaginal colonization, ascending intrauterine infection and conceptus tissue invasion by GBS. These strategies are crucial to potentially reduce the rate of preterm delivery and subsequent serious complications in the newborn