Reliability of the Hazelbaker Assessment Tool for Lingual Frenulum Function

BACKGROUND: About 3% of infants are born with a tongue-tie which may lead to breastfeeding problems such as ineffective latch, painful attachment or poor weight gain. The Hazelbaker Assessment Tool for Lingual Frenulum Function (HATLFF) has been developed to give a quantitative assessment of the tongue-tie and recommendation about frenotomy (release of the frenulum). The aim of this study was to assess the inter-rater reliability of the HATLFF. METHODS: Fifty-eight infants referred to the Breastfeeding Education and Support Services (BESS) at The Royal Women's Hospital for assessment of tongue-tie and 25 control infants were assessed by two clinicians independently. RESULTS: The Appearance items received kappas between about 0.4 to 0.6, which represents "moderate" reliability. The first three Function items (lateralization, lift and extension of tongue) had kappa values over 0.65 which indicates "substantial" agreement. The four Function items relating to infant sucking (spread, cupping, peristalsis and snapback) received low kappa values with insignificant p values. There was 96% agreement between the two assessors on the recommendation for frenotomy (kappa 0.92, excellent agreement). The study found that the Function Score can be more simply assessed using only the first three function items (ie not scoring the sucking items), with a cut-off of ≤4 for recommendation of frenotomy. CONCLUSION: We found that the HATLFF has a high reliability in a study of infants with tongue-tie and control infant

Violation of critical universality at the antiferromagnetic phase transition of YbRh2Si2

We report on precise low-temperature specific-heat measurements, C(T), of YbRh2Si2 in the vicinity of the antiferromagnetic phase transition on a single crystal of superior quality (RRR 150). We observe a very sharp peak at T_N=72mK with absolute values as high as C/T=8J/molK^2. A detailed analysis of the critical exponent \alpha around T_N reveals \alpha=0.38 which differs significantly from those of the conventional universality classes in the Ginzburg-Landau theory, where \alpha<0.11. Thermal-expansion measurements corroborate this large positive critical exponent. These results provide insight into the nature of the critical magnetic fluctuations at a temperature-driven phase transition close to a quantum critical point.Comment: Accepted for PR

Effect of chemical disorder on NiMnSb investigated by Appearance Potential Spectroscopy: a theoretical study

The half-Heusler alloy NiMnSb is one of the local-moment ferromagnets with unique properties for future applications. Band structure calculations predict exclusively majority bands at the Fermi level, thus indicating {100%} spin polarization there. As one thinks about applications and the design of functional materials, the influence of chemical disorder in these materials must be considered. The magnetization, spin polarization, and electronic structure are expected to be sensitive to structural and stoichiometric changes. In this contribution, we report on an investigation of the spin-dependent electronic structure of NiMnSb. We studied the influence of chemical disorder on the unoccupied electronic density of states by use of the ab-initio Coherent Potential Approximation method. The theoretical analysis is discussed along with corresponding spin-resolved Appearance Potential Spectroscopy measurements. Our theoretical approach describes the spectra as the fully-relativistic self-convolution of the matrix-element weighted, orbitally resolved density of states.Comment: JPD submitte

Evolution of Quantum Criticality in CeNi_{9-x}Cu_xGe_4

Crystal structure, specific heat, thermal expansion, magnetic susceptibility and electrical resistivity studies of the heavy fermion system CeNi_{9-x}Cu_xGe_4 (0 <= x <= 1) reveal a continuous tuning of the ground state by Ni/Cu substitution from an effectively fourfold degenerate non-magnetic Kondo ground state of CeNi_9Ge_4 (with pronounced non-Fermi-liquid features) towards a magnetically ordered, effectively twofold degenerate ground state in CeNi_8CuGe_4 with T_N = 175 +- 5 mK. Quantum critical behavior, C/T ~ \chi ~ -ln(T), is observed for x about 0.4. Hitherto, CeNi_{9-x}Cu_xGe_4 represents the first system where a substitution-driven quantum phase transition is connected not only with changes of the relative strength of Kondo effect and RKKY interaction, but also with a reduction of the effective crystal field ground state degeneracy.Comment: 15 pages, 9 figure

Ferromagnetic Kondo-Lattice Model

We present a many-body approach to the electronic and magnetic properties of the (multiband) Kondo-lattice model with ferromagnetic interband exchange. The coupling between itinerant conduction electrons and localized magnetic moments leads, on the one hand, to a distinct temperature-dependence of the electronic quasiparticle spectrum and, on the other hand, to magnetic properties, as e.~g.the Curie temperature T_C or the magnon dispersion, which are strongly influenced by the band electron selfenergy and therewith in particular by the carrier density. We present results for the single-band Kondo-lattice model in terms of quasiparticle densities of states and quasiparticle band structures and demonstrate the density-dependence of the self-consistently derived Curie temperature. The transition from weak-coupling (RKKY) to strong-coupling (double exchange) behaviour is worked out. The multiband model is combined with a tight-binding-LMTO bandstructure calculation to describe real magnetic materials. As an example we present results for the archetypal ferromagnetic local-moment systems EuO and EuS. The proposed method avoids the double counting of relevant interactions and takes into account the correct symmetry of atomic orbitals.Comment: 15 pages, 10 figure