Spectral splits of neutrinos as a BCS-BEC crossover type phenomenon

We show that the spectral split of a neutrino ensemble which initially consists of electron type neutrinos, is analogous to the BCS-BEC crossover already observed in ultra cold atomic gas experiments. Such a neutrino ensemble mimics the deleptonization burst of a core collapse supernova. Although these two phenomena belong to very different domains of physics, the propagation of neutrinos from highly interacting inner regions of the supernova to the vacuum is reminiscent of the evolution of Cooper pairs between weak and strong interaction regimes during the crossover. The Hamiltonians and the corresponding many-body states undergo very similar transformations if one replaces the pair quasispin of the latter with the neutrino isospin of the former.Comment: 9 pages, 5 figure

Heat transfer enhancement and pressure drop for fin-and-tube compact heat exchangers with delta winglet-type vortex generators

Heat transfer rate, pressure loss and efficiency are considered as the most important parameters in designing compact heat exchangers. Despite different types of heat exchangers, fin-and-tube compact heat exchangers are still common device in different industries due to the diversity of usage and the low space installation need. The efficiency of the compact heat exchanger can be increased by introducing the fins and increasing the heat transfer rate between the surface and the surroundings. Numerous modifications can be applied to the fin surface to increase heat transfer. Delta-winglet vortex generators (VGs) are known to enhance the heat transfer between the energy carrying fluid and the heat transfer surfaces in plate-fin-and-tube banks, but they have drawbacks as well. They increase the pressure loss and this should be considered. In this paper, the thermal efficiency of compact heat exchanger with VGs is investigated in different variations. The angle of attack, the length and horizontal and vertical position of winglet are the main parameters to consider. Numerical analyses are carried out to examine finned tube heat exchanger with winglets at the fin surface in a relatively low Reynolds number flow for the inline tube arrangements. The results showed that the length of the winglet significantly affects the improvement of heat transfer performance of the fin-and-tube compact heat exchangers with a moderate pressure loss penalty. In addition, the results show that the optimization cannot be performed for one criterion only. More parameters should be considered at the same time to run the process properly and improve the heat exchanger efficiency

High resolution melting curve assay for detecting rs12979860 IL28B polymorphisms involved in response of iranian patients to chronic hepatitis C treatment

Background: A recent genome-wide association study (GWAS) on patients with chronic hepatitis C (CHC) treated with peginterferon and ribavirin (pegIFN-α/RBV) identified a single nucleotide polymorphism (SNP) on chromosome 19 (rs12979860) which was strongly associated with a sustained virological response (SVR). The aim of this study was twofold: to study the relationship between IL28B rs12979860 and sustained virological response (SVR) to pegIFN-α/RVB therapy among CHC patients and to detect the rs12979860 polymorphism by high resolution melting curve (HRM) assay as a simple, fast, sensitive, and inexpensive method. Materials and Methods: The study examined outcomes in 100 patients with chronic hepatitis C in 2 provinces of Iran from December 2011 to June 2013. Two methods were applied to detect IL28B polymorphisms: PCR-sequencing as a gold standard method and HRM as a simple, fast, sensitive, and inexpensive method. Results: The frequencies of IL28B rs12979860 CC, CT, and TT alleles in chronic hepatitis C genotype 1a patients were 10 (10/100), 35 (35/100), and 6 (6/100) and in genotype 3a were 13 (13/100), 31 (31/100), and 5 (5/100), respectively. In genotype 3a infected patients, rs12979860 (CC and CT alleles) and in genotype 1a infected patients (CC allele) were significantly associated with a sustained virological response (SVR). The SVR rates for CC, CT and TT (IL28B rs12979860) were 18, 34 and 4, respectively. Multiple logistic regression analysis identified two independent factors that were significantly associated with SVR: IL-28B genotype (rs 12979860 CC vs TT and CT; odds ratio ORs, 7.86 and 4.084, respectively), and HCV subtype 1a (OR, 7.46). In the present study, an association between SVR rates and IL28B polymorphisms was observed. Conclusions: The HRM assay described herein is rapid, inexpensive, sensitive and accurate for detecting rs12979860 alleles in CHC patients. This method can be readily adopted by any molecular diagnostic laboratory with HRM capability and will be clinically beneficial in predicting treatment response in HCV genotype 1 and 3 infected patients. In addition, it was demonstrated that CC and CT alleles in HCV-3a and the CC allele in HCV-1a were significantly associated with response to pegIFN-α/RBV treatment. The present results may help identify subjects for whom the therapy might be successful

Investigation the integration of heliostat solar receiver to gas and combined cycles by energy, exergy, and economic point of views

Due to the high amount of natural gas resources in Iran, the gas cycle as one of the main important power production system is used to produce electricity. The gas cycle has some disadvantages such as power consumption of air compressors, which is a major part of gas turbine electrical production and a considerable reduction in electrical power production by increasing the environment temperature due to a reduction in air density and constant volumetric airflow through a gas cycle. To overcome these weaknesses, several methods are applied such as cooling the inlet air of the system by different methods and integration heat recovery steam generator (HRSG) with the gas cycle. In this paper, using a heliostat solar receiver (HSR) in gas and combined cycles are investigated by energy, exergy, and economic analyses in Tehran city. The heliostat solar receiver is used to heat the pressurized exhaust air from the air compressor in gas and combined cycles. The key parameter of the three mentioned analyses was calculated and compared by writing computer code in MATLAB software. Results showed the use of HSR in gas and combined cycles increase the annual average energy efficiency from 28.4% and 48.5% to 44% and 76.5%, respectively. Additionally, for exergy efficiency, these increases are from 29.2% and 49.8% to 45.2% and 78.5%, respectively. However, from an economic point of view, adding the HRSG increases the payback period (PP) and it decreases the net present value (NPV) and internal rate of return (IRR)

Comparison of contrast sensitivity in β-thalassemia patients treated by deferoxamine or deferasirox

Purpose: To compare contrast sensitivity (CS) in multi-transfused β-thalassemia patients who received deferoxamine with those who received Osveral. Methods: In this cross sectional study a total of 60 β-thalassemia patients (30 used deferoxamine and 30 used deferasirox) were regarded as case group and 30 age and sex matched healthy subjects were selected as control group. All subjects had a set of examinations including refraction, visual acuity, Biomicroscopy, ophthalmoscopy and CS. Contrast threshold was assessed with the use of Freiberg visual acuity and contrast test under the mesopic light condition for three frequencies; 1, 5, 15. cpd. All data analysis was performed using SPSS, version 17. Results: In visual acuity tests, thalassemic patients did not have any problem. Contrast threshold was higher in thalassemic patients who infuse deferoxamine (1.87. ±. 0.63, 1.46. ±. 0.81, and 2.96. ±. 1.68 in 1, 5, and 15. cpd, respectively) than that of those who intake deferasirox (1.74. ±. 0.80 (P = 0.743), 0.99. ±. 0.74 (P = 0.047), and 2.42. ±. 1.36 (P = 0.321) for 1, 5, and 15. cpd, respectively), and also than healthy patients (1.33. ±. 0.58 (P = 0.009), 0.95. ±. 0.68 (P = 0.022), and 2.24. ±. 1.23 (P = 0.135) for 1, 5, and 15. cpd, respectively). Comparing those who used deferasirox with healthy subjects, contrast threshold was higher in deferasirox group at all special frequencies (P >. 0.05). No significant relationship was observed between CS values and duration of transfusion, serum ferritin concentration and dose of chelation therapy (P >. 0.05). Conclusions: CS tests can detect visual disturbance in thalassemic patients before the impairment of visual acuity. It is suggested that CS tests be included in their regular eye examination. © 2018 Spanish General Council of Optometry

Comparison of contrast sensitivity in β-thalassemia patients treated by deferoxamine or deferasirox

Purpose: To compare contrast sensitivity (CS) in multi-transfused β-thalassemia patients who received deferoxamine with those who received Osveral. Methods: In this cross sectional study a total of 60 β-thalassemia patients (30 used deferoxamine and 30 used deferasirox) were regarded as case group and 30 age and sex matched healthy subjects were selected as control group. All subjects had a set of examinations including refraction, visual acuity, Biomicroscopy, ophthalmoscopy and CS. Contrast threshold was assessed with the use of Freiberg visual acuity and contrast test under the mesopic light condition for three frequencies; 1, 5, 15. cpd. All data analysis was performed using SPSS, version 17. Results: In visual acuity tests, thalassemic patients did not have any problem. Contrast threshold was higher in thalassemic patients who infuse deferoxamine (1.87. ±. 0.63, 1.46. ±. 0.81, and 2.96. ±. 1.68 in 1, 5, and 15. cpd, respectively) than that of those who intake deferasirox (1.74. ±. 0.80 (P = 0.743), 0.99. ±. 0.74 (P = 0.047), and 2.42. ±. 1.36 (P = 0.321) for 1, 5, and 15. cpd, respectively), and also than healthy patients (1.33. ±. 0.58 (P = 0.009), 0.95. ±. 0.68 (P = 0.022), and 2.24. ±. 1.23 (P = 0.135) for 1, 5, and 15. cpd, respectively). Comparing those who used deferasirox with healthy subjects, contrast threshold was higher in deferasirox group at all special frequencies (P >. 0.05). No significant relationship was observed between CS values and duration of transfusion, serum ferritin concentration and dose of chelation therapy (P >. 0.05). Conclusions: CS tests can detect visual disturbance in thalassemic patients before the impairment of visual acuity. It is suggested that CS tests be included in their regular eye examination. © 2018 Spanish General Council of Optometry