Partial dietary fish meal replacement with cotton seed meal and supplementation with exogenous protease alters growth, feed performance, hematological indices and associated gene expression markers (GH, IGF-I) for Nile tilapia, Oreochromis niloticus

A 12-week feeding trial was conducted to evaluate the effect of different ratios of fish meal (FM): cotton seed meal (CSM) without or with inclusion of exogenous protease in diets on growth performance, hematology, digestibility and selected gene expression markers (GH and I (IGF-I) of juvenile Nile tilapia. The experimental diets were categorized into three groups; the first group CSM1 which contained fish meal protein: cotton seed meal protein (FM: CSM = 2:1), the second group CSM2 which contained FM: CSM = 1:1 and the third one CSM3 contained FM: CSM = 1:2 on protein content based. All groups were supplemented with exogenous protease at 0 and 2500 U kg−1 diet, respectively. All diets were fed to fish (initial body weight 11.62 ± 0.03 g fish−1) in triplicate aquaria twice daily. The higher weight gain (WG), protein efficiency ratio (PER) and best feed conversion ratio (FCR) were recorded by fish fed CSM1 and CSM2 and supplemented with 2500 U protease/kg diet. The highest apparent digestibility coefficient of crude protein, crude lipid and digestible energy, and apparent availability coefficient of essential amino acids were obtained by fish receiving CSM1 and CSM2 supplemented with protease (2500 U protease kg−1 diet). The highest mean values of Hb, Htc and RBCs were recorded in fish fed CSM1 and CSM2 supplemented with protease enzyme (2500 U protease kg−1 diet). Serum of alanine and aspartate aminotransferase activities were improved due to dietary protease (2500 U protease kg−1 diet) supplementation, also, fish received the diets supplemented with protease 2500 U kg−1 diet generally had higher total protein, albumin, calcium and phosphorus than those fed diets without supplement. The highest growth hormone (GH) gene expression in brain and liver of tilapia were obtained in the group fed CSM3 and un-supplemented with protease enzyme followed by CSM2 (un-supplemented). On the other hand, tilapia fed CSM1 and CSM2 supplemented with protease enzyme showed the highest values of gene expression of insulin like growth factor I (IGF-I) in brain and liver of tilapia compared to other groups. Results above showed that supplementation of protease can improve growth, nutrient assimilation, and hematology and alter gene expression of GH and IGF-I of Nile tilapia

Formation and Evolution of Supermassive Black Holes

The correlation between the mass of supermassive black holes in galaxy nuclei and the mass of the galaxy spheroids or bulges (or more precisely their central velocity dispersion), suggests a common formation scenario for galaxies and their central black holes. The growth of bulges and black holes can commonly proceed through external gas accretion or hierarchical mergers, and are both related to starbursts. Internal dynamical processes control and regulate the rate of mass accretion. Self-regulation and feedback are the key of the correlation. It is possible that the growth of one component, either BH or bulge, takes over, breaking the correlation, as in Narrow Line Seyfert 1 objects. The formation of supermassive black holes can begin early in the universe, from the collapse of Population III, and then through gas accretion. The active black holes can then play a significant role in the re-ionization of the universe. The nuclear activity is now frequently invoked as a feedback to star formation in galaxies, and even more spectacularly in cooling flows. The growth of SMBH is certainly there self-regulated. SMBHs perturb their local environment, and the mergers of binary SMBHs help to heat and destroy central stellar cusps. The interpretation of the X-ray background yields important constraints on the history of AGN activity and obscuration, and the census of AGN at low and at high redshifts reveals the downsizing effect, already observed for star formation. History appears quite different for bright QSO and low-luminosity AGN: the first grow rapidly at high z, and their number density decreases then sharply, while the density of low-luminosity objects peaks more recently, and then decreases smoothly.Comment: 31 pages, 13 figures, review paper for Astrophysics Update

Observing Supermassive Black Holes across cosmic time: from phenomenology to physics

In the last decade, a combination of high sensitivity, high spatial resolution observations and of coordinated multi-wavelength surveys has revolutionized our view of extra-galactic black hole (BH) astrophysics. We now know that supermassive black holes reside in the nuclei of almost every galaxy, grow over cosmological times by accreting matter, interact and merge with each other, and in the process liberate enormous amounts of energy that influence dramatically the evolution of the surrounding gas and stars, providing a powerful self-regulatory mechanism for galaxy formation. The different energetic phenomena associated to growing black holes and Active Galactic Nuclei (AGN), their cosmological evolution and the observational techniques used to unveil them, are the subject of this chapter. In particular, I will focus my attention on the connection between the theory of high-energy astrophysical processes giving rise to the observed emission in AGN, the observable imprints they leave at different wavelengths, and the methods used to uncover them in a statistically robust way. I will show how such a combined effort of theorists and observers have led us to unveil most of the SMBH growth over a large fraction of the age of the Universe, but that nagging uncertainties remain, preventing us from fully understating the exact role of black holes in the complex process of galaxy and large-scale structure formation, assembly and evolution.Comment: 46 pages, 21 figures. This review article appears as a chapter in the book: "Astrophysical Black Holes", Haardt, F., Gorini, V., Moschella, U and Treves A. (Eds), 2015, Springer International Publishing AG, Cha

Effect of synbiotics between Bacillus licheniformis and yeast extract on growth, hematological and biochemical indices of the Nile tilapia (Oreochromis niloticus)

Twelve practical diets were formulated to contain four levels of Bacillus licheniformis (0.0, 0.24 × 106, 0.48 × 106 and 0.96 × 106 CFU g−1), respectively, with three yeast extract levels (0%, 0.5% and 1%), respectively. Each diet was randomly assigned to duplicate groups of 50 Nile tilapia (Oreochromis niloticus) (5.99 ± 0.03 g) in 24 concrete ponds (0.5 m3 and 1.25 m depth) for 12 weeks. Increasing dietary B. licheniformis levels in O. niloticus and yeast extract levels significantly (P < 0.01) improved growth performance and nutrient utilization. Supplementation of the experimental diets with, 0.48 × 106 CFU/g−1 and 1.0% yeast extract showed the best nutrient utilization compared to other treatments. All probiotic levels significantly (P < 0.01) increased chemical composition (P < 0.05) compared to the control group, while increasing yeast extract did not significantly alter chemical composition. Hematological indices, total protein and albumin of O. niloticus significantly increased while aspartate aminotransferase and alanine aminotransferase significantly (P < 0.01) decreased with an increase in B. licheniformis level up to 0.48 × 106 CFU g−1. Increasing levels of yeast extract had no effect on hematological parameters and the diets supplemented with 0.48 × 106 CFU g−1 and 0.5% yeast extract showed the highest hematological values

Comparison of early effects of right ventricular apical pacing on left ventricular functions in single and dual chamber pacemakers

Objectives: Our study aimed to demonstrate the early negative impact of right ventricular apical pacing induced by single (VVI) and dual chamber (DDD) pacemakers on LV functions in patients with preserved EF. And to assess that single brain natriuretic peptide (BNP) after 2 months of implantation is correlated to ventricular dyssynchrony. Methods: 40 patients with implanted VVI and DDD pacemakers were examined before implantation and again after 2 and 6 months of implantation for BNP, left ventricular (LV) systolic and diastolic functions by echocardiography and pulsed tissue Doppler. After 6 months, patients with DDD pacemakers were crossed over to VVI mode of pacing for 2 weeks with lower rate programed to 60 beat per minute then sample for BNP was collected again. Results: There was no statistically significant difference in LV systolic and diastolic functions except for myocardial performance index (MPI) with (P value of 0.03). Mean BNP level in VVI pacing was higher than DDD pacing after two months with P value = 0.001 while comparison after 6 months showed P value = 0.023. There was a statistically significant difference between both groups in results of aortic preejection delay (APED) (P value of <0.05). BNP was correlated to APED (r = 0.651 and P value = 0.001) and pacing percentage (r = 0.687 and P value = 0.00). Conclusion: Loss of atrioventricular synchrony in VVI mode leads to a significant difference in LV dyssynchrony between both groups. BNP level is correlated to LV dyssynchrony and pacing percentage