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The critical behavior of single phase Y2Fe17 melt-spun ribbons with the Th2Fe17-type crystal structure has been studied around the transition temperature (TC). This alloy undergoes a second-order ferromagnetic (FM)–paramagnetic (PM) phase transition at TC = 301 K. Various techniques, such as the modified Arrott plot, Kouvel–Fisher method, and critical isotherm analysis, were used to determine the critical exponents that were found to be β = 0.226(3), γ = 1.296(2), and δ = 6.804(5). The universality class of the critical phenomenon in the Y2Fe17 ribbons can be explained with the help of the renormalization group theory approach, in which the magnetic properties show a feature changing from three (3D)- to two-dimensional (2D) Ising model. The first-principles calculations based on density functional theory qualitatively explain the experimental results, confirming the strong correlation between lattice atoms and critical behavior in magnetic intermetallic Y2Fe17. [ABSTRACT FROM AUTHOR]

We have studied the magnetic coupling property, magnetic entropy change, and magnetic phase transition behavior of ternary alloy Ce 1. 3 Pr 0. 7 Co 7 . It exhibits a typical paramagnetic–ferromagnetic phase transition at T C = 2 1 8  K and this phase transition is verified to be second order by the scaling theory. Based on the data of isothermal magnetization measured around T C , we obtained the variation of its magnetic entropy change under the different magnetic fields but it only shows a smaller entropy change value. Density functional calculations confirm that the extra magnetic interaction originates from the Pr-Pr exchange interactions, which yields anomalous magnetic coupling with Co-Co (Ce-Ce) exchange interactions. One phenomenological model is suggested to understand anomalous magnetic behavior observed in the present intermetallic compounds. [ABSTRACT FROM AUTHOR]

Background: Humanitarian surgical organizations provide palatoplasties for patients without access to surgical care. Few organizations have evaluated the outcomes of these trips. This study evaluates the palatal fistula rate in patients from two cohorts in rural China and one in the United States., Methods: This study compared the odds of fistula formation among three cohorts whose palates were repaired between 2005 and 2009. One cohort included 97 Chinese patients operated on by teams from the United States and Canada under the auspices of Resurge International. They were compared to cohorts at Huaxi Stomatology Hospital and the University of California San Francisco (UCSF). Age, fistula presence, and Veau class were compared among cohorts using Chi-square tests. Logistic regression was used to analyze predictors of fistula formation., Results: The fistula risk was 35.4% in patients treated by humanitarian teams, 12.8% at Huaxi University Hospital and 2.5% at UCSF ( P < 0.001). Age and Veau class were associated with fistula formation (Age P = 0.0015; Veau P < 0.001). ReSurge and Huaxi patients had 20.2 and 5.6 times the odds of developing a fistula, respectively, compared to UCSF patients ( P < 0.01, both). A multivariable model controlling for surgical group, age, and gender showed an association between Veau class and the odds of fistula formation., Conclusions: Chinese children undergoing palatoplasty by international teams had higher odds of palatal fistula than children treated by Chinese surgeons in established institutions and children treated in the United States. More research is required to identify factors affecting complication rates in low-resource environments.