Measurement of the energy barrier distribution in the antiferromagnetic layer of exchange-biased materials

The value of exchange field of two FeMn–NiFeCobased spin valves with varying thickness of the pinned ferromagnetic layer has been determined as a function of temperature. The complexities caused by thermal activation of the antiferromagnet during measurement have been overcome by the development of a measurement protocol. The values of the exchange field obtained provide a measure of the degree of order in the antiferromagnet. Thus it is possible to determine the distribution of energy barriers to reversal for the system. We find that for a 110-A -thick pinned NiFeCo layer a broad distribution exists, whereas for an 80-A layer, the distribution is bimodal and has a component subject to thermal activation at temperatures down to 260 K

Bu haftaki konumuz:Darüşşafaka Lisesi

Taha Toros Arşivi, Dosya No: 58-Darüşşafaka. Taha Toros Arşivi, Dosya No: 58-Darüşşafaka. Not: Gazetenin "Her Hafta Bir Sohbet" köşesinde yayımlanmıştır

Splenectomy for immune thrombocytopenia : our 11-year experience

Splenectomy has been practiced for the treatment of ITP for the past few decades. Currently it is utilised when a patient is either dependent or resistant to steroid treatment and the platelet count remains less than 30×109/L. Recently new agents have been added to the armamentarium used to treat ITP, including immune-suppressants such as rituximab and the new thrombopoetin-receptor agonists. This has brought into question the role of surgery for the treatment of ITP, and the need to compare the response and complication rates of splenectomy to these newer agents. Historic studies done on splenectomy for the treatment of ITP have been performed in the setting of low HIV prevalence. There is a relative paucity of data on the response rate in HIV-associated thrombocytopenia to splenectomy and the durability of response to splenectomy is unclear in this patient population. We retrospectively analysed 73 consecutive patients who underwent splenectomy for ITP from 2001 to 2011. The primary objective was to determine the rate of complete response, this was defined as a platelet count greater than 100×109/L at one year post splenectomy. Results were compared between HIV positive and HIV negative patients. The secondary objectives were: to evaluate the intra-operative and post†operative complications and mortality in the HIV positive and HIV negative groups, and to investigate for associations between co-morbidities, pre-operative treatment and response to splenectomy

Positive Action: Implementing a Social-Emotional and Character Development Program in Marshall County, Kentucky Schools

Approximately 8% to 10% of children less than 5 years old experience clinically significant mental health problems, and 10–20% of all children and adolescents have a mental health problem of some type. While the prevalence of mental illness is similar between rural and urban residents, the services available differ significantly. Less than half of rural counties have a mental health facility that provides outpatient treatment for children and adolescents, resulting in children and adolescents in these areas being largely underserved. Following family homes, schools are the primary locations responsible for youth development. Research shows that well- designed, well-implemented school-based prevention programs can significantly reduce health- risk behaviors among all students. In rural areas lacking mental health services, school-based mental health interventions can reach youth whose needs would otherwise go unmet. Positive Action is a school-based, social-emotional and character development program spanning Pre- Kindergarten through 12th grade. Positive Action is an evidence-based program developing healthy mental and behavioral patterns in youth using age-specific curriculum. Using a one group time series design, we propose to implement Positive Action in three public schools in rural Marshall County, Kentucky

Single top channel in association with H→bb̄ production at ATLAS : a feasible study

A degeneracy in the minima of the profile likelihood function of the Higgs boson coupling to fermions and bosons, where boson couplings are assumed to be positive, is reported by both ATLAS and CMS. Although one minimum lies in the region of positive fermionic coupling scale factors, consistent with the Standard Model, the second minimum lies in the negative region-a region which would indicate new physics. This degeneracy can potentially be resolved by studying a fermionic-bosonic interference that takes place in the single top quark production in association with a Higgs particle, in which the cross-section is significantly enhanced for anomalous coupling values. A truth level feasibility study of the tH process with H→bb̄ is conducted at 8 TeV and 21 fb-¹ of integrated luminosity. the equivalent of the 2012 run at the LHC. A sensitivity of l.7σ is found for the enhanced case of a coupling scale factor of cF = -1. This is insufficient for a detection. A projection to 14 TeV centre-of-mass energies indicates that at truth-level a 3σ significance with 15 fb-¹ of integrated luminosity can be reached for the enhanced case. However, assuming as low as 5% systematic uncertainty lowers this to below 2σ across the whole luminosity range, indicating that the upcoming run at LHC will also be insufficient to resolve the degeneracy