The overall efficiency with which Milky Way Giant Molecular Clouds (GMCs) is forming stars was determined by deriving an equation using density of cloud (i.e. stellar density/ total cloud density), which is the core parameter that determines star formation other than the mass of cloud, and comparing with mass (i.e. stellar mass/ total gas mass) as was propounded by previous researchers, to ascertain the reasons the observed star formation efficiency of Milky Way Giant Molecular Clouds () is low. This will aid understanding the physical factors behind the formation of stars from interstellar gas and develop a predictive theory of star formation and evolution of galaxies. A total of 191 star formation complexes-giant molecular cloud (SFC-GMC) complexes was used in estimating the following cloud parameters: density as 93.8218 solar mass/parsec squared, average stellar density as 2.67872 solar mass/parsec squared, average luminosity as 9.87E24 solar luminosity, average effective temperature as 498,647 solar temperature, average stellar radius as 51.4522 parsec and average cloud radius as 325507 parsec as well as the total mass in stars M harbored by the individual clouds (20,831 solar mass), which was inferred from Wilkinson Microwave Anisotropy probe (WMAP) free-free. Finally, the overall efficiency with which Milky Way Giant Molecular Clouds is forming star gave 0.0289573 which is less than the previous estimate as 0.030849, showing that not all the masses of the cloud were present at the end of the star formation, and this reduction in mass are caused by magnetic field, supersonic turbulence, self-regulation and unbound states of its internal structure, which are the reasons the observed star formation efficiencies are low.

We present our result on the Eddington ratios and accretion rates of 13,516 Seyfert galaxies consisting of 6,758 Seyfert 1s and 6,758 Seyfert 2s. These objects under study are a sub-sample of 91,006 Seyfert galaxies from SDSS-DR14. Using the separation criterion > 3 for Seyfert 2 galaxies, the 91,006 objects are separated into Seyferts 1s and 2s and we further select Hidden broadline region (HBLR) Seyfert 2s. Our results show that Seyfert 1 galaxies have higher Eddington ratio that Seyfert 2s an indication that Seyfert 1 galaxies may be more AGN-dominated than Seyfert 2 galaxies. We find the mean luminosity of the doubly ionized oxygen line () to be higher in Seyfert 2 galaxies a pointer that narrow line regions (NLRs) in Seyfert 2s may contain higher density of cloud of particles than Seyfert 1s. In addition, () is found to increase with increasing Eddington ratio which shows that the NLR is likely to be illuminated by the central region; a precursor that the central region and the NRL should be few parsecs apart. The observation we make that Seyferts 1 and 2 of equal black hole mass (=) have diametrically unequal Eddington ratio of log=8.9638 for Seyfert 2s and log=5.801 for Seyfert 1s suggests that each of the Seyfert classes may have been associated with different AGN activities. On accretion rate, Seyfert 2 galaxies have higher accretion rate which implies that they are probably in the gravitational force era dominated by absorption by matter while Seyfert 1s are probably in the radiation force dominated era and as such not associated with absorption by matter.

We present statistical results from a very large sample of Seyfert galaxies (217,272 galaxies) obtained from SDSS DR10 (Sloan Digital Sky Survey Data Release 10). From their observed parameters which includes; flux of hydrogen alpha (Hα), luminosity distance and velocity dispersion, we computed other relevant parameters such as; bolometric luminosity, black hole mass and mass accretion rate, which enabled us classify these Seyfert galaxies into Seyfert 1s (188,486 galaxies) and Seyfert 2s (28,786 galaxies). Analyses on these computed parameters revealed that Seyfert 2 galaxies were less luminous, more massive and accrete less matter than the Seyfert 1 galaxies. Further analysis on Seyfert 2s based on their mass accretion rate led to their classification into hidden broad line region (HBLR) Seyfert 2s (12,988 galaxies) and non-hidden broad line region (non-HBLR) Seyfert 2s (15,798 galaxies) which shows that, the HBLR S2s accrete more matter than the non-HBLR S2s. All the results obtained suggest that the bolometric luminosity alone is not sufficient in determining the extent of the existence of the BLR in Seyfert 2 galaxies rather the mass accretion rate should be taking into consideration in determining the appearance and disappearance of the BLR.

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