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A cubic Sr2FeCrO6−y phase, for which no crystallographic data has been previously reported, was synthesized through sol–gel assisted method for the first time. EDTA and chitosan were used as chelating agents. Calcining and subsequent argon-annealing techniques were used. Analysis of the product by SQUID magnetometry showed that the material exhibited possible spin-glass transition or superparamagnetic behaviour below 50 K. The control of phase formation of the Sr2FexCr2−xO6−y (SFCO) system has been improved and the mechanisms of phase formation were better understood. With further investigations, it is hoped that SFCO series materials will be utilized in the manufacturing of electronic devices, fuel cells and other engineering areas. [ABSTRACT FROM AUTHOR]

Presents a letter to the editor in response to the article that discusses the etiology of disseminated paracoccidiodomycosis, published in the previous issue of the "Eye."

Recent experimental results have emphasized two aspects of Tb2 Ti2 O7, which have not been taken into account in previous attempts to construct theories of Tb2 Ti2 O7: the role of small levels of structural disorder, which appears to control the formation of a long-range ordered state of as yet unknown nature, and the importance of strong coupling between spin and lattice degrees of freedom, which results in the hybridization of crystal-field excitons and transverse acoustic phonons. In this work, we examine the juncture of these two phenomena and show that samples with strongly contrasting behavior vis-a-vis the structural disorder (i.e., with and without the transition to the ordered state), develop identical magnetoelastic coupling. We also show that the comparison between single-crystal and powder samples is more complicated than previously thought--the correlation between the lattice parameter (as a measure of superstoichiometric Tb3+) and the existence of a specific heat peak, as observed in powder samples, does not hold for single crystals. [ABSTRACT FROM AUTHOR]

Determining the fate of the Pauling entropy in the classical spin ice material Dy2Ti2O7 with respect to the third law of thermodynamics has become an important test case for understanding the existence and stability of ice-rule states in general. The standard model of spin ice--the dipolar spin ice model--predicts an ordering transition at T≈0.15 K, but recent experiments by Pomaranski et al. suggest an entropy recovery over long timescales at temperatures as high as 0.5 K, much too high to be compatible with the theory. Using neutron scattering and specific heat measurements at low temperatures and with long timescales (0.35 K/106 s and 0.5 K/105 s, respectively) on several isotopically enriched samples, we find no evidence of a reduction of ice-rule correlations or spin entropy. High-resolution simulations of the neutron structure factor show that the spin correlations remain well described by the dipolar spin ice model at all temperatures. Furthermore, by careful consideration of hyperfine contributions, we conclude that the original entropy measurements of Ramirez et al. are, after all, essentially correct: The short-time relaxation method used in that study gives a reasonably accurate estimate of the equilibrium spin ice entropy due to a cancellation of contributions. [ABSTRACT FROM AUTHOR]

We present a model of the lattice dynamics of the rare-earth titanate pyrochlores R2 Ti2 O7 (R=Tb,Dy,Ho), which are important materials in the study of frustrated magnetism. The phonon modes are obtained by density functional calculations, and these predictions are verified by comparison with scattering experiments. Single crystal inelastic neutron scattering is used to measure acoustic phonons along high symmetry directions for R=Tb, Ho; single crystal inelastic x-ray scattering is used to measure numerous optical modes throughout the Brillouin zone for R=Ho; and powder inelastic neutron scattering is used to estimate the phonon density of states for R=Tb, Dy, Ho. Good agreement between the calculations and all measurements is obtained, allowing confident assignment of the energies and symmetries of the phonons in these materials under ambient conditions. Knowledge of the phonon spectrum is important for understanding spin-lattice interactions, and can be expected to be transferred readily to other members of the series to guide the search for unconventional magnetic excitations. [ABSTRACT FROM AUTHOR]

At low temperatures, Tb2Ti2O7 enters a spin liquid state, despite expectations of magnetic order and/or a structural distortion. Using neutron scattering, we have discovered that in this spin liquid state an excited crystal field level is coupled to a transverse acoustic phonon, forming a hybrid excitation. Magnetic and phononlike branches with identical dispersion relations can be identified, and the hybridization vanishes in the paramagnetic state. We suggest that Tb2Ti2O7 is aptly named a "magnetoelastic spin liquid" and that the hybridization of the excitations suppresses both magnetic ordering and the structural distortion. The spin liquid phase of Tb2Ti2O7 can now be regarded as a Coulomb phase with propagating bosonic spin excitations. [ABSTRACT FROM AUTHOR]

Background: Enactivism and active inference are two important concepts in the field of osteopathy. While enactivism emphasizes the role of the body and the environment in shaping our experiences and understanding of the world, active inference emphasizes the role of action and perception in shaping our experiences and understanding of the world. Together, these frameworks provide a unique perspective on the practice of osteopathy, and how it can be used to facilitate positive change in patients. Since the neonatal period is a crucial time for development, osteopaths should aim to create a therapeutic relationship. Arguably, through participatory sense-making, osteopaths can help the baby build a generative model (with positive priors) to deal with stress and needs throughout their life., Aim: Since the literature considers that interactions with the environment, which enact the patients' experiences, depending on contextual factors and communication between patient and caregiver, this research explored whether there is a correspondence between the indications in the literature and clinical practice in the management of the mother/parent-child dyad during osteopathic care on children aged 0 to 2 years old., Methods: Semi-structured interviews were conducted with a purposive sample of nine osteopaths with experience in the field of pediatrics. Interviews were transcribed verbatim, and constructivist grounded theory was used to conceptualize, collect and analyze data. Codes and categories were actively constructed through an interpretive/constructionist paradigm., Results: The core category was the idea of the pediatric osteopath as a support for the family, not only for the child. Four additional categories were identified: (1) Preparing a safe environment for both children and parents, (2) Communication, (3) Attachment and synchrony, and (4) Synchronization., Conclusion: Through participatory sense-making, osteopaths manage contextual factors to establish an effective therapeutic alliance through the osteopath-parent-child triad to facilitate the construction of the child's internal generative model to promote healthy development. The therapeutic encounter is considered an encounter between embodied subjects, occurring within a field of affordances (ecological niche) that allows the interlocutors to actively participate in creating new meanings through interpersonal synchronization. Participatory sense-making and the establishment of a therapeutic alliance through the osteopath-parent-child triad are crucial to promote healthy development in the child., Competing Interests: CA, LB, and JE were employed by Malta ICOM Educational Ltd. The remaining author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The reviewer GR declared a past co-authorship with the authors FC, JE to the handling editor., (Copyright © 2023 Accardi, Cerritelli, Bovo and Esteves.)

Graphite is an inexpensive material with useful electrical, magnetic, thermal, and optical properties. It is also biocompatible and used universally as a substrate. Micrometer-sized graphitic particles in solution are therefore ideal candidates for novel lab-on-a-chip and remote manipulation applications in biomedicine, biophysics, chemistry, and condensed-matter physics. However, submerged graphite is not known to be amenable to magnetic manipulation, the optimal manipulation method for such applications. Here, we exploit the diamagnetism of graphite and demonstrate contactless magnetic positioning control of graphitic microflakes in diamagnetic aqueous solutions. We develop a theoretical model for magnetic manipulation of graphite microflakes and demonstrate experimentally magnetic transport of such particles over distances [Formula: see text] with peak velocities [Formula: see text] in inhomogeneous magnetic fields. We achieve fully biocompatible transport for lipid-coated graphite in NaCl aqueous solution, paving the way for previously undiscovered biomedical applications. Our results prove that micrometer-sized graphite can be magnetically manipulated in liquid media., Competing Interests: The authors declare no conflict of interest., (Copyright © 2019 the Author(s). Published by PNAS.)

Layer-by-layer epitaxial growth of the pyrochlore magnet Tb 2 Ti 2 O 7 on the isostructural substrate Y 2 Ti 2 O 7 results in high-quality single crystal films of up to 60 nm thickness. Substrate-induced strain is shown to act as a strong and controlled perturbation to the exotic magnetism of Tb 2 Ti 2 O 7 , opening up the general prospect of strain-engineering the diverse magnetic and electrical properties of pyrochlore oxides.

January, 1992, to September, 1994, a hundred and seventy-eight blunt chest trauma patients were examined with plain chest films and detailed rib studies. The patients were subdivided into three groups according to: a) the presence/absence of rib fractures correlated with clinical data; b) the depiction of rib fractures and/or thoracic complications; c) treatment customization in the presence/absence of rib fractures. In our series of patients the clinical data and the presence of rib fractures were poorly correlated. The detection rates of minor and major complications were also investigated on plain chest films and detailed rib studies. Plain chest films most frequently depicted the complications requiring conservative or surgical management and gave the indication for further imaging investigations. The detailed rib studies of the involved hemithorax yielded no further information useful to therapy except in few cases: and should therefore be limited to the cases exhibiting complications on chest films, which may benefit from surgical fixation. The accurate study of rib fractures is paramount in the cases where legal action may be undertaken.