Thermodynamic transport theory of spin waves in ferromagnetic insulators

We use the Boltzmann transport theory in the relaxation time approximation to describe the thermal transport of spin waves in a ferromagnet. By treating spin waves as magnon excitations we are able to compute analytically and numerically the coefficients of the constitutive thermo-magnetic transport equations. As a main result, we find that the absolute thermo-magnetic power coefficient $\epsilon_M$, relating the gradient of the potential of the magnetization current and the gradient of the temperature, in the limit of low temperature and low field, is a constant $\epsilon_M = -0.6419 \, k_B/\mu_B$. The theory correctly describes the low-temperature and magnetic-field dependencies of spin Seebeck experiments. Furthermore, the theory predicts that in the limit of very low temperatures the spin Peltier coefficient $\Pi_M$, relating the heat and the magnetization currents, tends to a finite value which depends on the amplitude of the magnetic field. This indicates the possibility to exploit the spin Peltier effect as an efficient cooling mechanism in cryogenics.Comment: (v1) PDFLaTeX, 10 pages, 5 figures, 1 table, submitted to Phys. Rev. B; (v2) PDFLaTeX, 12 pages, 5 figures, 1 table; Secs. I, III, IV highly improved, old-Sec. VI splitted into two new Secs. VI-VII, references added, typos corrected, revised version re-submitted to Phys. Rev. B; (v3) PDFLaTeX, 12 pages, 5 figures, 1 table; Refs. [3], [27], [36] updated, final version published in Phys. Rev.

Ab-initio based analytical evaluation of entropy in magnetocaloric materials with first order phase transitions

We combine spin polarised density functional theory and thermodynamic mean field theory to describe the phase transitions of antiperovskite manganese nitrides. We find that the inclusion of the localized spin contribution to the entropy, evaluated through mean field theory, lowers the transition temperatures. Furthermore, we show that the electronic entropy leads to first order phase transitions in agreement with experiments whereas the localized spin contribution adds second order character to the transition. We compare our predictions to available experimental data to assess the validity of the assumptions underpinning our multilevel modelling.Comment: PDFLaTeX, 10 pages, 4 figures, 2 tables, accepted for publication in Physics Procedia as ICM 2015 Conference Proceedin

Kinetics of heat flux avalanches at the first order transition in La(Fe-Mn-Si)13_{13}-H1.65_{1.65} compounds

We study heat flux avalanches occurring at the first order transition in La(Fe-Mn-Si)$_{13}$-H$_{1.65}$ magnetocaloric material. As the transition is associated to the phase boundaries motion that gives rise to the latent heat, we develop a non equilibrium thermodynamic model. By comparing the model with experimental calorimetry data available for Mn=0.18, we find the values of the intrinsic kinetic parameter $R_L$, expressing the damping for the moving boundary interface, at different magnetic fields. We conclude that by increasing field, thus approaching the critical point, the avalanches increase in number and their kinetics is slowed down.Comment: PDFLaTeX, 5 pages, 2 figures, 1 table, accepted for publication in Journal of Physics: Conference Series as Conference Proceeding of JEMS 2016 (8th Joint European Magnetic Symposia

The pure B−LB-L model and future linear colliders: the Higgs sector

We summarise the phenomenology of the Higgs sector of the minimal $B-L$ extension of the Standard Model at an $e^+e^-$ Linear Collider. Within such a scenario, we show that (in comparison with the Large Hadron Collider) several novel production and decay channels involving the two physical Higgs states could experimentally be accessed at such a machine. In particular, we present the scope of the $Z'$ strahlung process for single and double Higgs production, the only suitable mechanism for accessing an almost decoupled heavy scalar state.Comment: This proceeding of the 2011 International Workshop on Future Linear Colliders (LCWS11) is published through the SLAC Electronic Conference Proceedings Archiv

Charged-Higgs production in the Two-Higgs-Doublet Model --- the \tau\nu channel

We update the allowed parameter space of the CP-violating 2HDM with Type II Yukawa couplings, that survives the current experimental and theoretical constraints on the model. For a representative set of allowed parameter points, we study the production of charged Higgs bosons, both at the LHC at 14 TeV and at a possible future hadronic collider at 30 TeV. Two classes of production mechanisms are considered, "bosonic" (pp\to H^\pm W^\mp X) and "fermionic" (pp \to H^+ \bar t (b) X). After commenting on our previous H^\pm\to W^\pm H_1 investigation, we focus on the tauonic decay mode, H^\pm \to \tau\nu, performing a detailed signal-over-background analysis at the parton level. The increased features provided when considering CP violation, i.e., the extension of the parameter space and the mixing of the would-be CP-odd scalar boson, only marginally increase the discovery prospects, which remain very challenging both when increased luminosities and higher energies are considered.Comment: 26 pages, 13 figures. v2 Version published in JHE

Editorial: Management and Treatment of Pilonidal Disease: 189 Years After Mayo

...Pilonidal Disease (PD) was first scientifically reported 189 years ago by Herbert Mayo, back in 1833, as a sinus containing hair follicles located in the sacrococcygeal region of a female patien

Prognostic role of minimal residual disease before and after hematopoietic stem cell transplantation in childhood acute lymphoblastic leukemia

More than 80% of children with acute lymphoblastic leukemia (ALL) can be cured through intensive and risk-oriented chemotherapy protocols. Allogeneic hematopoietic stem cell transplantation (HSCT) is considered bene\ufb01cial for approximately 10% of the patients who are at veryhigh risk at frontline therapy and for the majority of patients after relapse. Consequently, it is critically important to identify prognostic factors in this group of patients in order to tailor risk-adapted therapy. In this retrospective study, we aimed to assess the prognostic role of minimal residual disease (MRD) before HSCT and at di\ufb00erent time points after transplantation in children with ALL

Prognostic Value of Plasma and Urine Glycosaminoglycan Scores in Clear Cell Renal Cell Carcinoma

The prognosis of metastatic clear cell renal cell carcinoma (ccRCC) vastly improved since the introduction of antiangiogenic targeted therapy. However, it is still unclear which biological processes underlie ccRCC aggressiveness and affect prognosis. Here, we checked whether a recently discovered systems biomarker based on plasmatic or urinary measurements of glycosaminoglycans aggregated into diagnostic scores correlated with ccRCC prognosis.Thirty-one patients with a diagnosis of ccRCC (23 metastatic) were prospectively enrolled and their urine and plasma biomarker scores were correlated to progression-free survival (PFS) and overall survival (OS) as either a dichotomous (Low vs. High) or a continuous variable in a multivariate survival analysis.The survival difference between High vs. Low-scored patients was significant in the case of urine scores (2-year PFS rate = 53.3% vs. 100%, p = 310-4 and 2-year OS rate = 73.3% vs. 100%, p = 0.0078) and in the case of OS for plasma scores (2-year PFS rate = 60% vs. 84%, p = 0.0591 and 2-year OS rate = 66.7% vs. 90%, p = 0.0206). In multivariate analysis, the urine biomarker score was an independent predictor of PFS (HR: 4.62, 95% CI: 1.66 to 12.83, p = 0.003) and OS (HR: 10.13, 95% CI: 1.80 to 57.04, p = 0.009).This is the first report on an association between plasma or urine GAG scores and the prognosis of ccRCC patients. Prospective trials validating the prognostic and predictive role of this novel systems biomarker are warranted