107 research outputs found

    Social network sites as educational factors

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    Background: In this present era, the technology development has established certain type of communication. Nowadays education as the fundamental principle in transferring cognition to the learners has found various methods. Recently the concept that social networks could be effective tool in easing the achievement to the educational goals has been under attention. Therefore, this investigation is trying to find out whether, the social networks could play role on the process of education among students? Materials and Methods: This cross sectional descriptive study was performed on 1000 students from 7 medical universities in 2015. The data collection tool was questionnaire that was approved Cronbach's alpha was 0.85. Meanwhile its validity was confirmed too. The obtained data were analyzed by the descriptive statistic, ANOVA, Turkey and used X2 SPSS-19. Results: In this investigation, 940 subjects were under study. 85 used daily the social network. The highest usage was attributed to the Telegram. 52 preferred image suitable for transferring of information. Even though, 73 believed that these networks have significant effects on coordinating of students with in university charges. Conclusion: Considering the findings of the present study, it is proposed that the universities integrate the social networks in the education programs and recognize it as the awareness factor, therefore benefit it in the educational affairs. © 2016 Alireza Ebrahimpour, Farnaz Rajabali, Fatemeh Yazdanfar, Reza Azarbad, Majid Rezaei Nodeh, Hasan Siamian, Mohammad Vahedi

    Beta decay of 71,73Co; probing single particle states approaching doubly magic 78Ni

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    Low-energy excited states in 71,73Ni populated via the {\beta} decay of 71,73Co were investigated in an experiment performed at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University (MSU). Detailed analysis led to the construction of level schemes of 71,73Ni, which are interpreted using systematics and analyzed using shell model calculations. The 5/2- states attributed to the the f5/2 orbital and positive parity 5/2+ and 7/2+ states from the g9/2 orbital have been identified in both 71,73Ni. In 71Ni the location of a 1/2- {\beta}-decaying isomer is proposed and limits are suggested as to the location of the isomer in 73Ni. The location of positive parity cluster states are also identified in 71,73Ni. Beta-delayed neutron branching ratios obtained from this data are given for both 71,73Co.Comment: Accepted for publication in PR

    β-decay studies of the transitional nucleus Cu75 and the structure of Zn75

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    The β decay of Cu75 [t1/2=1.222(8)s] to levels in Zn75 was studied at the Holifield Radioactive Ion Beam Facility of Oak Ridge National Laboratory. The γγ and βγ data were collected at the Low-energy Radioactive Ion Beam Spectroscopy Station using the high-resolution isobar separator to obtain a purified Cu75 beam with a rate of over 2000 ions per second. The excited states in Zn75 have been identified for the first time. A total of 120 γ-ray transitions were placed in a level scheme containing 59 levels including two states above the neutron separation energy and a previously unknown 1/2- isomeric state at 127 keV. Spins and parities of several states were deduced and interpreted based on the observed β feeding and γ-decay pattern. © 2011 American Physical Society

    βdecays of \u3csup\u3e92\u3c/sup\u3eRb, \u3csup\u3e96gs\u3c/sup\u3eY, and \u3csup\u3e142\u3c/sup\u3eCs measured with the modular total absorption spectrometer and the influence of multiplicity on total absorption spectrometry measurements

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    Total absorption spectroscopy is a technique that helps obtain reliable β-feeding patterns of complex decays important for nuclear structure and astrophysics modeling as well as decay heat analysis in nuclear reactors. The need for improved measurements of β-feeding patterns from fission decay products has come to the forefront of experiments that use nuclear reactors as a source of antineutrinos. Here we present more detailed results, in particular the β-decay measurements of 96gsY, and demonstrate the impact of the β-delayed γ multiplicity on the overall efficiency of Modular Total Absorption Spectrometer used at Oak Ridge National Laboratory to study the decays of fission products abundant during a nuclear fuel cycle

    The Spread of HIV in Pakistan: Bridging of the Epidemic between Populations

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    In the last two decades, ‘concentrated epidemics’ of human immunodeficiency virus (HIV) have established in several high risk groups in Pakistan, including Injecting Drug Users (IDUs) and among men who have sex with men (MSM). To explore the transmission patterns of HIV infection in these major high-risk groups of Pakistan, 76 HIV samples were analyzed from MSM, their female spouses and children, along with 26 samples from a previously studied cohort of IDUs. Phylogenetic analysis of HIV gag gene sequences obtained from these samples indicated a substantial degree of intermixing between the IDU and MSM populations, suggesting a bridging of HIV infection from IDUs, via MSM, to the MSM spouses and children. HIV epidemic in Pakistan is now spreading to the female spouses and offspring of bisexual MSM. HIV control and awareness programs must be refocused to include IDUs, MSM, as well as bisexual MSM, and their spouses and children

    Decays of the Three Top Contributors to the Reactor ν - e High-Energy Spectrum, Rb 92, y 96gs, and Cs 142, Studied with Total Absorption Spectroscopy

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    We report total absorption spectroscopy measurements of Rb92, Y96gs, and Cs142 β decays, which are the most important contributors to the high energy ν-e spectral shape in nuclear reactors. These three β decays contribute 43% of the ν-e flux near 5.5 MeV emitted by nuclear reactors. This ν-e energy is particularly interesting due to spectral features recently observed in several experiments including the Daya Bay, Double Chooz, and RENO Collaborations. Measurements were conducted at Oak Ridge National Laboratory by means of proton-induced fission of U238 with on-line mass separation of fission fragments and the Modular Total Absorption Spectrometer. We observe a β-decay pattern that is similar to recent measurements of Rb92, with a ground-state to ground-state β feeding of 91(3)%. We verify the Y96gs ground-state to ground-state β feeding of 95.5(20)%. Our measurements substantially modify the β-decay feedings of Cs142, reducing the β feeding to Ba142 states below 2 MeV by 32% when compared with the latest evaluations. Our results increase the discrepancy between the observed and the expected reactor ν-e flux between 5 and 7 MeV, the maximum excess increases from ∼10% to ∼12%

    Updated β -decay measurement of neutron-rich Cu 74

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    The β decay of neutron-rich Cu74 has been studied at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory. By using a high-resolution mass separator a purified Cu74 beam was obtained, thus allowing decay through its isobar chain to stable Ge74 without any decay chain member dominating. A total of 170γ rays were associated with Cu74β decay with 111 placed in the Zn74 level scheme. Updated β feeding intensities and estimated log(ft) values are presented, and new Jπ assignments are proposed using shell model calculations. The progression of simulated total absorption γ-ray spectroscopy (TAGS) based on proposed levels and β-feeding values from previous measurements to this evaluation are presented and demonstrate the need for a TAGS measurements for this and similar decays

    First Evidence of Axial Shape Asymmetry and Configuration Coexistence in 74^{74}Zn: Suggestion for a Northern Extension of the N=40N=40 Island of Inversion

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    The excited states of N=44N=44 74^{74}Zn were investigated via γ\gamma-ray spectroscopy following 74^{74}Cu β\beta decay. By exploiting γ\gamma-γ\gamma angular correlation analysis, the 22+2_2^+, 31+3_1^+, 02+0_2^+ and 23+2_3^+ states in 74^{74}Zn were firmly established. The γ\gamma-ray branching and E2/M1E2/M1 mixing ratios for transitions de-exciting the 22+2_2^+, 31+3_1^+ and 23+2_3^+ states were measured, allowing for the extraction of relative B(E2)B(E2) values. In particular, the 23+02+2_3^+ \to 0_2^+ and 23+41+2_3^+ \to 4_1^+ transitions were observed for the first time. The results show excellent agreement with new microscopic large-scale shell-model calculations, and are discussed in terms of underlying shapes, as well as the role of neutron excitations across the N=40N=40 gap. Enhanced axial shape asymmetry (triaxiality) is suggested to characterize 74^{74}Zn in its ground state. Furthermore, an excited K=0K=0 band with a significantly larger softness in its shape is identified. A shore of the N=40N=40 ``island of inversion'' appears to manifest above Z=26Z=26, previously thought as its northern limit in the chart of the nuclides

    Scattering of the Halo Nucleus Be 11 on Au 197 at Energies around the Coulomb Barrier

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    Angular distributions of the elastic, inelastic, and breakup cross sections of the halo nucleus Be11 on Au197 were measured at energies below (Elab=31.9 MeV) and around (39.6 MeV) the Coulomb barrier. These three channels were unambiguously separated for the first time for reactions of Be11 on a high-Z target at low energies. The experiment was performed at TRIUMF (Vancouver, Canada). The differential cross sections were compared with three different calculations: semiclassical, inert-core continuum-coupled-channels and continuum-coupled-channels ones with including core deformation. These results show conclusively that the elastic and inelastic differential cross sections can only be accounted for if core-excited admixtures are taken into account. The cross sections for these channels strongly depend on the B(E1) distribution in Be11, and the reaction mechanism is sensitive to the entanglement of core and halo degrees of freedom in Be11
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