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Model of Charged Anisotropic Strange Stars in Minimally Coupled fR Gravity
No full textIn the present article, we have investigated a new family of nonsingular solutions of static relativistic compact sphere which incorporates the characteristics of anisotropic fluid and electromagnetic field in the context of minimally coupled fR theory of gravity. The strange matter MIT bag model equation of state (EoS) has been considered along with the usual forms of the Karori–Barua KB metric potentials. For this purpose, we derived the Einstein–Maxwell field equations in the assistance of strange matter EoS and KB type ansatz by employing the two viable and cosmologically well-consistent models of fR=R+γR2 and fR=R+γRR+αR2. Thereafter, we have checked the physical acceptability of the proposed results such as pressure, energy density, energy conditions, TOV equation, stability conditions, mass function, compactness, and surface redshift by using graphical representation. Moreover, we have investigated that the energy density and radial pressure are nonsingular at the core or free from central singularity and always regular at every interior point of the compact sphere. The numerical values of such parameters along with the surface density, charge to radius ratio, and bag constant are computed for three well-known compact stars such as CS1SAXJ1808.4−3658 (x˜=7.07 km, CS2VelaX−1x˜=9.56 km, and CS34U1820−30x˜=10 km and are presented in Tables 1–6. Conclusively, we have noticed that our presented charged compact stellar object in the background of two well-known fR models obeys all the necessary conditions for the stable equilibrium position and which is also perfectly fit to compose the strange quark star object
Differential diagnosis of benign ovarian cysts using tumor markers in serum and cyst fluid
No full textBackground: Differentiating the type of benign ovarian cyst can result in better care.
Aims: To measure CA-125, CA 19-9, Carcinoembryonic Antigen (CEA) and Alpha-fetoprotein (AFP) in serum and cyst fluid of patients with benign ovarian cysts and whether these biomarkers can be used to identify the type of the cyst.
Methods and materials: Patients with benign ovarian cysts undergoing laparoscopic cystectomy were included. Cyst types were determined histologically. Levels of CA 125, CA 19-9, CEA and AFP were measured in serum and cyst fluid.
Results: 98 cysts (25 functional, 12 endometrioma, 15 dermoid, 28 mucinous cystadenoma, 18 serous cystadenoma) were evaluated. There was a significant difference in levels of CA 125 and CA 19-9 in serum and CA-125, CA 19-9 and CEA in cyst fluid. For diagnostic purposes, a value of ≥35 IU/mL for serum CA 125 predicted endometriomas with a sensitivity of 91.7% and a specificity of 91.9%. A value of ≤22.5 IU/mL for cyst fluid CA 19-9, predicted functional cysts with a of sensitivity of 92% and specificity of 95.2%. A value of ≥100 ng/mL for cyst fluid CEA, predicted mucinous cysts with a sensitivity of 96.4% and specificity of 96.7%.
Conclusion: Levels of CA-125, CA 19-9 and CEA in serum and cyst fluid of patients with benign ovarian cysts can be used as a diagnostic tool in patient evaluation with acceptable sensitivity and specificity. This finding can be used in conjunction with other methods such as ultrasound, especially in cases that are harder to diagnose
Effect of sildenafil citrate on prediabetic and diabetic albino rats treated with metformin
No full textDiabetes Miletus (DM) is a global epidemic disease. It is estimated that there are already 415 million adults aged 20–79 years diabetics worldwide. Sildenafil citrate is a phosphodiesterase type 5 (PDE5) inhibitor, which increases cyclic guanosine monophosphate (cGMP) and metformin (MET) is a biguanide used for the treatment of type 2 diabetes which increases peripheral insulin sensitivity.
Aim: This study aims to assess the effect of sildenafil citrate and metformin on lipid profile and glycemic control in diabetic and prediabetic albino rats.
Materials and methods: Adult male albino rats are used and divided into nine groups each group consists of 10 rats, diabetes is induced by feeding a high-fat diet (HFD) for an initial period of 2 weeks followed by a single intraperitoneal injection of (35 mg/kg) Streptozotocin. Prediabetes is induced by feeding (HFD) and glucose in water for a period of 2 weeks. Sildenafil was given in a dose of (5 &10 mg/kg/day orally for 4 weeks), metformin was given in a dose of (50 &100 mg/kg/day orally for 4 weeks) using oral gavages to normal healthy rats, diabetic and prediabetic rats. Blood samples were collected after 4 weeks of treatment in all experimental groups.
Results: Combined administration of sildenafil and metformin on diabetic rats improving hyperglycemia, oxidative stress, and hyperlipidemia induced by streptozotocin than the administration of metformin or sildenafil alone.
Conclusion: Sildenafil has beneficial effects against some diabetic complications. The present study showed that sildenafil with metformin has beneficial effects against diabetic complications
Myoinositol with Metformin and Myoinositol alone in infertile PCOS women undergoing ovulation induction cycles: A comparative study
No full textBackground: This was a prospective observational study conducted over a twelve-month duration in our institute to compare the combined effect of metformin and myoinositol with metformin alone. Method: A total of sixty patients were included in the study, and they were divided into two groups depending on whether they were given the combination or the single drug. Group A (n=30) was given Myoinositol 600 mg+Metformin 500 mg thrice a day, and Group B ( n=30) was given only Myoinositol 600 mg thrice a day. The outcome measure was clinical pregnancy rate and improvement in clinical and hormonal parameters after drug therapy. Results: BMI (p<0.01), modified Ferriman Gallaway score (p>0.05), and the was a significant improvement in the hormonal parameters (LH,FSH) in both the groups and the levels were found to be comparable after a period of 6 months. The clinical pregnancy rate after six cycles of ovulation was significantly higher in Group A as compared to Group B. In Group A, the total clinical pregnancy rate was 43.33%, and in Group B, it was 26.67%, respectively, and the end of 6 months and the difference was statistically significant (p = <0.01) Conclusion: Equal response in reduction of hormonal levels and clinical and laboratory parameters were seen in both groups, while better results in terms of clinical fertility rates were observed in the group that was given a combination of myoinositol with metformin
Scaling Laws in the Stellar Mass Distribution and the Transition to Homogeneity
No full textWe present a new statistical analysis of the large-scale stellar mass distribution in the Sloan Digital Sky Survey (data release 7). A set of volume-limited samples shows that the stellar mass of galaxies is concentrated in a range of galaxy luminosities that is very different from the range selected by the usual analysis of galaxy positions. Nevertheless, the two-point correlation function is a power-law with the usual exponent γ=1.71−1.82, which varies with luminosity. The mass concentration property allows us to make a meaningful analysis of the angular distribution of the full flux-limited sample. With this analysis, after suppressing the shot noise, we extend further the scaling range and thus obtain γ=1.83 and a clustering length r0=5.8−7.0h−1Mpc. Fractional statistical moments of the coarse-grained stellar mass density exhibit multifractal scaling. Our results support a multifractal model with a transition to homogeneity at about 10h−1Mpc
Effect of sildenafil citrate on prediabetic and diabetic albino rats treated with metformin
No full textDiabetes Miletus (DM) is a global epidemic disease. It is estimated that there are already 415 million adults aged 20–79 years diabetics worldwide. Sildenafil citrate is a phosphodiesterase type 5 (PDE5) inhibitor, which increases cyclic guanosine monophosphate (cGMP) and metformin (MET) is a biguanide used for the treatment of type 2 diabetes which increases peripheral insulin sensitivity.
Aim: This study aims to assess the effect of sildenafil citrate and metformin on lipid profile and glycemic control in diabetic and prediabetic albino rats.
Materials and methods: Adult male albino rats are used and divided into nine groups each group consists of 10 rats, diabetes is induced by feeding a high-fat diet (HFD) for an initial period of 2 weeks followed by a single intraperitoneal injection of (35 mg/kg) Streptozotocin. Prediabetes is induced by feeding (HFD) and glucose in water for a period of 2 weeks. Sildenafil was given in a dose of (5 &10 mg/kg/day orally for 4 weeks), metformin was given in a dose of (50 &100 mg/kg/day orally for 4 weeks) using oral gavages to normal healthy rats, diabetic and prediabetic rats. Blood samples were collected after 4 weeks of treatment in all experimental groups.
Results: Combined administration of sildenafil and metformin on diabetic rats improving hyperglycemia, oxidative stress, and hyperlipidemia induced by streptozotocin than the administration of metformin or sildenafil alone.
Conclusion: Sildenafil has beneficial effects against some diabetic complications. The present study showed that sildenafil with metformin has beneficial effects against diabetic complications
A Generic Embedding Class-I Model via Karmarkar Condition in fℛ,T Gravity
No full textIn the present work, we investigate the existence of compact star model in the background of fℛ,T gravity theory, where ℛ represents the Ricci scalar and T refers to the energy-momentum tensor trace. Here, we use Karmarkar condition for the interior stellar setup so that a complete and precise model following the embedding class-I strategy can be obtained. For this purpose, we assume anisotropic matter contents along with static and spherically symmetric geometry of compact star. As Karmarkar embedding condition yields a relationship of metric potentials, therefore we assume a suitable form for one of the metric components as eϕ=ar2+bn−1rn+1, where a and b represent constants and n is a free parameter, and evaluate the other. We approximate the values of physical parameters like a,A, and B by utilizing the known values of mass and radius for the compact star Vela X-1. The validity of the acquired model is then explored for different values of coupling parameter λ graphically. It is found that the resulting solution is physically interesting and well-behaved
Conformable Fractional Models of the Stellar Helium Burning via Artificial Neural Networks
No full textThe helium burning phase represents the second stage that the star used to consume nuclear fuel in its interior. In this stage, the three elements, carbon, oxygen, and neon, are synthesized. The present paper is twofold: firstly, it develops an analytical solution to the system of the conformable fractional differential equations of the helium burning network, where we used, for this purpose, the series expansion method and obtained recurrence relations for the product abundances, that is, helium, carbon, oxygen, and neon. Using four different initial abundances, we calculated 44 gas models covering the range of the fractional parameter α=0.5−1 with step Δα=0.05. We found that the effects of the fractional parameter on the product abundances are small which coincides with the results obtained by a previous study. Secondly, we introduced the mathematical model of the neural network (NN) and developed a neural network algorithm to simulate the helium burning network using a feed-forward process. A comparison between the NN and the analytical models revealed very good agreement for all gas models. We found that NN could be considered as a powerful tool to solve and model nuclear burning networks and could be applied to the other nuclear stellar burning networks
A Numerical Approach to Study Ablation of Large Bolides: Application to Chelyabinsk
No full textIn this study, we investigate the ablation properties of bolides capable of producing meteorites. The casual dashcam recordings from many locations of the Chelyabinsk superbolide associated with the atmospheric entry of an 18 m in diameter near-Earth object (NEO) have provided an excellent opportunity to reconstruct its atmospheric trajectory, deceleration, and heliocentric orbit. In this study, we focus on the study of the ablation properties of the Chelyabinsk bolide on the basis of its deceleration and fragmentation. We explore whether meteoroids exhibiting abrupt fragmentation can be studied by analyzing segments of the trajectory that do not include a disruption episode. We apply that approach to the lower part of the trajectory of the Chelyabinsk bolide to demonstrate that the obtained parameters are consistent. To do that, we implemented a numerical (Runge–Kutta) method appropriate for deriving the ablation properties of bolides based on observations. The method was successfully tested with the cases previously published in the literature. Our model yields fits that agree with observations reasonably well. It also produces a good fit to the main observed characteristics of Chelyabinsk superbolide and provides its averaged ablation coefficient σ = 0.034 s2 km−2. Our study also explores the main implications for impact hazard, concluding that tens of meters in diameter NEOs encountering the Earth in grazing trajectories and exhibiting low geocentric velocities are penetrating deeper into the atmosphere than previously thought and, as such, are capable of producing meteorites and even damage on the ground
Surgical repair of thoracic aortic aneurysm and dissection in the Sub-Saharan Africa: 30-day outcomes from a Cameroonian Center
No full textThe real incidence of thoracic aorta aneurysm and dissection (TAA) in the sub-Saharan region is unknown. Owing to diagnostic limitations and the absence of specialized centers, reports on TAA surgery have been anecdotal. We report our 30-day outcomes over an 8-year period following TAA surgery at the Shisong Cardiac Center, a Cameroonian cardio-surgical institution. Between November 2010 and May 2018, TAA was diagnosed in 35 patients at the Shisong Cardiac Center. Twenty eight (n=28) patients underwent surgical repair during the same period [Mean age: 43.8plusmn;14.7 years, range: 18-72 years; males: 18/28 (64.2%)]. Patient profiles, disease etiology and surgical outcomes were retrospectively reviewed. Uncontrolled hypertension was the commonest risk factor (17/28, 60.7%). Genetic disorders were found in 5/28 patients (17.8%) including 4 with bicuspid aortic valve and 1 with Marfanrsquo;s Syndrome. The operative mortality was 10.7% (n=3/28). Twenty one (n=22/28, 75%) patients had composite aortic root replacement (Bentall and De Bono); four patients (n=4/28, 14.2%) had ascending aorta graft replacement and two patients (n=2/28, 7.1%) underwent reductive aortoplasty (Robiscek). Associated procedures were mitral surgery (4/28, 14.2%), tricuspid repair (3/28, 10.7%) and CABG (1/28, 3.5%). One case of stroke was reported in the immediate postoperative period. The incidence of TAA in the sub-Saharan region seems to be underestimated due mainly to insufficient number of specialists and medical infrastructures. A major attention should be paid during the evaluation of patients with risk factors. These early results demonstrate the feasibility of surgical correction in our country with encouraging results.
Key words: Thoracic aneurysm, aneurysm repair, Sub-Saharan Africa