Influence Of The Strong Magnetocrystalline Anisotropy On The Magnetocaloric Properties Of Mnp Single Crystal

Manganese monophosphate MnP single crystal deserves attention due to its rich magnetic phase diagram, which is quite different depending on the direction of the applied magnetic field. Generally speaking, it has a Curie temperature around 291 K and several other magnetic arrangements at low temperatures (cone-, screw-, fan-, and ferromagnetic-type structures). This richness is due to the strong magnetocrystalline anisotropy. In this sense, the present paper makes a thorough description of the influence of this anisotropy on the magnetocaloric properties of this material. From a fundamental view we could point out, among those several magnetic arrangements, the most stable one. On the other hand, from an applied view, we could show that the magnetic entropy change around room temperature ranges from -4.7 to -3.2 J kg K, when the magnetic field (5 T) is applied along the easy and hard magnetization directions, respectively. 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Incidence of factor VIII inhibitors throughout life in severe hemophilia A in the United Kingdom

The age-adjusted incidence of new factor VIII inhibitors was analyzed in all United Kingdom patients with severe hemophilia A between 1990 and 2009. Three hundred fifteen new inhibitors were reported to the National Hemophilia Database in 2528 patients with severe hemophilia who were followed up for a median (interquartile range) of 12 (4-19) years. One hundred sixty (51%) of these arose in patients ≥ 5 years of age after a median (interquartile range) of 6 (4-11) years' follow-up. The incidence of new inhibitors was 64.29 per 1000 treatment-years in patients < 5 years of age and 5.31 per 1000 treatment-years at age 10-49 years, rising significantly (P = .01) to 10.49 per 1000 treatment-years in patients more than 60 years of age. Factor VIII inhibitors arise in patients with hemophilia A throughout life with a bimodal risk, being greatest in early childhood and in old age. HIV was associated with significantly fewer new inhibitors. The inhibitor incidence rate ratio in HIV-seropositive patients was 0.32 times that observed in HIV-seronegative patients (P < .001). Further study is required to explore the natural history of later-onset factor VIII inhibitors and to investigate other potential risk factors for inhibitor development in previously treated patients