Changes of digestive enzymes activity in common carp (Cyprinus carpio) during larval ontogeny

This study was aimed to gain knowledge on the ontogeny of digestive enzymes in common carp larvae at the governmental Warm Water Fish Aquaculture Center of Shahid Rajaee in Sari, Mazandaran, Iran. The ontogenetic development of pancreatic (trypsin, chymotrypsin, lipase and α-amylase) and intestinal (alkaline phosphatase and aminopeptidase-N) enzymes were assessed in common carp larvae from first feeding (3 days post hatching) to 33 days post hatching (dph). The larvae started to feed on rotifers at day 3 to day 7. Feeding on a commercial diet was started from day-8 onwards. Specific trypsin and chymotrypsin activities feed with rotifer were 0.011 U/mg protein and 0.003 U/mg protein at day 7, respectively; then the specific activities feed with dry food reached a maximum level at 33 dph (0.028 U/mg protein and 0.028 U/mg protein, respectively) (P<0.05) compared to live prey. The elevated alkaline proteases activity can be related to adaptation of larvae to digest protein content in the food. Specific lipase activity was 0.0006 U/mg protein at 7 dph; then the activity feed with dry food reached a maximum level at 15 dph (0.0011 U/mg protein) (P<0.05) compared to live prey. Specific α-amylase activity feed with rotifer was 85.86 U/mg protein on the 7 dph; consequently, its specific activity reached a maximum level at 15 dph (128.77 U/mg protein) (P<0.05). Specific alkaline phosphatase and aminopeptidase N activities feed with rotifer were 6 U/mg protein and 0.0106 U/mg protein at day 7, respectively; then the specific activities feed with dry food reached a maximum level at 33 dph (28.66 U/mg protein and 0.58 U/mg protein, respectively) (P<0.05) compared to live prey

About Gravitomagnetism

The gravitomagnetic field is the force exerted by a moving body on the basis of the intriguing interplay between geometry and dynamics which is the analog to the magnetic field of a moving charged body in electromagnetism. The existence of such a field has been demonstrated based on special relativity approach and also by special relativity plus the gravitational time dilation for two different cases, a moving infinite line and a uniformly moving point mass, respectively. We treat these two approaches when the applied cases are switched while appropriate key points are employed. Thus, we demonstrate that the strength of the resulted gravitomagnetic field in the latter approach is twice the former. Then, we also discuss the full linearized general relativity and show that it should give the same strength for gravitomagnetic field as the latter approach. Hence, through an exact analogy with the electrodynamic equations, we present an argument in order to indicate the best definition amongst those considered in this issue in the literature. Finally, we investigate the gravitomagnetic effects and consequences of different definitions on the geodesic equation including the second order approximation terms.Comment: 16 pages, a few amendments have been performed and a new section has been adde

Quantum mechanics and geodesic deviation in the brane world

We investigate the induced geodesic deviation equations in the brane world models, in which all the matter forces except gravity are confined on the 3-brane. Also, the Newtonian limit of induced geodesic deviation equation is studied. We show that in the first Randall-Sundrum model the Bohr-Sommerfeld quantization rule is as a result of consistency between the geodesic and geodesic deviation equations. This indicates that the path of test particle is made up of integral multiples of a fundamental Compton-type unit of length $h/mc$.Comment: 5 pages, no figure

On Higher Order Gravities, Their Analogy to GR, and Dimensional Dependent Version of Duff's Trace Anomaly Relation

An almost brief, though lengthy, review introduction about the long history of higher order gravities and their applications, as employed in the literature, is provided. We review the analogous procedure between higher order gravities and GR, as described in our previous works, in order to highlight its important achievements. Amongst which are presentation of an easy classification of higher order Lagrangians and its employment as a \emph{criteria} in order to distinguish correct metric theories of gravity. For example, it does not permit the inclusion of only one of the second order Lagrangians in \emph{isolation}. But, it does allow the inclusion of the cosmological term. We also discuss on the compatibility of our procedure and the Mach idea. We derive a dimensional dependent version of Duff's trace anomaly relation, which in \emph{four}-dimension is the same as the usual Duff relation. The Lanczos Lagrangian satisfies this new constraint in \emph{any} dimension. The square of the Weyl tensor identically satisfies it independent of dimension, however, this Lagrangian satisfies the previous relation only in three and four dimensions.Comment: 30 pages, added reference

Horizon Problem Remediation via Deformed Phase Space

We investigate the effects of a special kind of dynamical deformation between the momenta of the scalar field of the Brans-Dicke theory and the scale factor of the FRW metric. This special choice of deformation includes linearly a deformation parameter. We trace the deformation footprints in the cosmological equations of motion when the BD coupling parameter goes to infinity. One class of the solutions gives a constant scale factor in the late time that confirms the previous result obtained via another approach in the literature. This effect can be interpreted as a quantum gravity footprint in the coarse grained explanation. The another class of the solutions removes the big bang singularity, and the accelerating expansion region has an infinite temporal range which overcomes the horizon problem. After this epoch, there is a graceful exiting by which the universe enters in the radiation dominated era.Comment: 13 pages, 2 figures, to appear in GER

Chameleonic Generalized Brans--Dicke model and late-time acceleration

In this paper we consider Chameleonic Generalized Brans--Dicke Cosmology in the framework of FRW universes. The bouncing solution and phantom crossing is investigated for the model. Two independent cosmological tests: Cosmological Redshift Drift (CRD) and distance modulus are applied to test the model with the observation.Comment: 20 pages, 15 figures, to be published in Astrophys. Space Sci. (2011

FRW Cosmology From Five Dimensional Vacuum Brans-Dicke Theory

We follow approach of induced matter theory for 5D vacuum BD, introduce induced matter and potential in 4D hypersurfaces, and employ generalized FRW type solution. We confine ourselves to scalar field and scale factors be functions of the time. This makes the induced potential, by its definition, vanishes. When the scale factor of fifth dimension and scalar field are not constants, 5D eqs for any geometry admit a power law relation between scalar field and scale factor of fifth dimension. Hence the procedure exhibits that 5D vacuum FRW like eqs are equivalent, in general, to corresponding 4D vacuum ones with the same spatial scale factor but new scalar field and coupling constant. We show that 5D vacuum FRW like eqs or its equivalent 4D vacuum ones admit accelerated solutions. For constant scalar field, eqs reduce to usual FRW eqs with typical radiation dominated universe. For this situation we obtain dynamics of scale factors for any geometry without any priori assumption. For nonconstant scalar fields and spatially flat geometries, solutions are found to be power law and exponential ones. We also employ weak energy condition for induced matter, that allows negative/positive pressures. All types of solutions fulfill WEC in different ranges. The power law solutions with negative/positive pressures admit both decelerating and accelerating ones. Some solutions accept shrinking extra dimension. By considering nonghost scalar fields and recent observational measurements, solutions are more restricted. We illustrate that accelerating power law solutions, which satisfy WEC and have nonghost fields, are compatible with recent observations in ranges -4/3 < \omega </- -1.3151 and 1.5208 </- n < 1.9583 for dependence of fifth dimension scale factor with usual scale factor. These ranges also fulfill condition nonghost fields in the equivalent 4D vacuum BD eqs.Comment: 18 pages, 16 figures, 11 table

Naked Singularity Formation In f(R) Gravity

We study the gravitational collapse of a star with barotropic equation of state $p=w\rho$ in the context of $f({\mathcal R})$ theories of gravity. Utilizing the metric formalism, we rewrite the field equations as those of Brans-Dicke theory with vanishing coupling parameter. By choosing the functionality of Ricci scalar as $f({\mathcal R})=\alpha{\mathcal R}^{m}$, we show that for an appropriate initial value of the energy density, if $\alpha$ and $m$ satisfy certain conditions, the resulting singularity would be naked, violating the cosmic censorship conjecture. These conditions are the ratio of the mass function to the area radius of the collapsing ball, negativity of the effective pressure, and the time behavior of the Kretschmann scalar. Also, as long as parameter $\alpha$ obeys certain conditions, the satisfaction of the weak energy condition is guaranteed by the collapsing configuration.Comment: 15 pages, 4 figures, to appear in GR

Omega-3 fatty acid supplements improve the cardiovascular risk profile of subjects with metabolic syndrome, including markers of inflammation and auto-immunity

OBJECTIVE Fish-oil contains high concentrations of omega-3 fatty acids that have been shown to have anti-inflammatory properties. We have evaluated the effects of purified omega-3 fatty acid supplements on several anthropometric and biochemical parameters, including heat shock protein (Hsp) 27 antibody titres in subjects with metabolic syndrome. METHODS Subjects (n = 120) with metabolic syndrome (mean age of 52.9 +/- 11.9 years) were randomly allocated to one of two groups: sixty subjects were given 1 gram of fish oil as a single capsule, containing 180 mg eicosapentaenoic acid and 120 mg docosahexaenoic acid daily for 6 months. Control subjects did not receive any supplementation over the same period. RESULTS The study was completed by 47 subjects in the intervention group and 42 subjects in the control group. Treatment with omega 3 supplements was associated with a significant fall in body weight (P < 0.05), systolic blood pressures (P < 0.05), serum low density lipoprotein cholesterol (P < 0.05), and total cholesterol (P < 0.05), triglycerides (P < 0.05), high-sensitivity C-reactive protein (hs-CRP) (P < 0.01), and Hsp27 antibody titres (P < 0.05). No significant changes were observed in the control group. CONCLUSION It appears that omega 3 improves the cardiovascular risk profile of subjects with metabolic syndrome, having effects on weight, systolic blood pressure, lipid profile and markers of inflammation and autoimmunit

Pulmonary complications in primary hypogammaglobulinemia: a survey by high resolution CT scan

Background. Primary hypogammaglobulinemia disorders are a group of heterogeneous immunodeficiency syndromes with an increased susceptibility to pulmonary complications. Methods. The aim of this study was to evaluate the extent of lung abnormalities in primary hypogammaglobulinaemic patients by high resolution computed tomography (HRCT) scan and pulmonary function test (PFT). HRCT and PFT were performed in 22 Iranian patients with primary hypogammaglobulinemia. Results. Pathological bronchial findings were observed in thirteen patients: three patients showed only peribronchial thickening and the remaining ten patients suffered from both bronchiectasis and peribronchial wall thickening. Mild type of bronchiectasis and peribronchial wall thickening were the most common type, predominantly observed in the right middle and both right and left lower lobe segments of lungs. Although bullae were not found, emphysema, air-trapping, and collapse/consolidation were observed in two patients. Bronchial involvement was mostly limited to 1 up to 5 bronchopulmonary segments; only one HRCT indicated bronchial involvement in more than nine bronchopulmonary segments. Pathological bronchial findings mostly observed in the proximal bronchi; meanwhile the involvement of the distal bronchi was less common. Decreasing FEV1 and FVC were observed in 65% and 55% of patients, respectively. There was a significant correlation between the HRCT score and the predicted values by PFT. The delay of diagnosis in patients with bronchiectasis was significantly higher than those without bronchiectasis. Conclusions. It seems that the majority of hypogammaglobulinaemic patients suffer from the mild type of bronchiectasis, which is mostly observed in the proximal bronchi of the lower lobe segments. The delay of diagnosis plays an important role in the occurrence of this complication in these patients