Chirality-dependent transmission of spin waves through domain walls

Spin-wave technology (magnonics) has the potential to further reduce the size and energy consumption of information processing devices. In the submicrometer regime (exchange spin waves), topological defects such as domain walls may constitute active elements to manipulate spin waves and perform logic operations. We predict that spin waves that pass through a domain wall in an ultrathin perpendicular-anisotropy film experience a phase shift that depends on the orientation of the domain wall (chirality). The effect, which is absent in bulk materials, originates from the interfacial Dzyaloshinskii-Moriya interaction and can be interpreted as a geometric phase. We demonstrate analytically and by means of micromagnetic simulations that the phase shift is strong enough to switch between constructive and destructive interference. The two chirality states of the domain wall may serve as a memory bit or spin-wave switch in magnonic devices.Comment: 11 pages, 10 figures (incl. supp. mat.); Phys. Rev. Lett. (accepted

Una reflexión sobre la importancia de la enseñanza de la shoá en Argentina

Este ensayo propone compartir algunos dilemas encontrados al momento de redactar un Proyecto de Ley para la incorporación de la temática Holocausto – Shoá en los contenidos de los currículos escolares de la provincia de Buenos Aires. Finalizada la tarea, se hizo necesario dar cuenta de algunos problemas que fueron surgiendo a lo largo del trabajo. Una de las cuestiones prioritarias quedó trazada cuando apareció la pregunta sobre ¿Por qué debería ser el Holocausto Judío un tema de enseñanza vigente en las sociedades presentes? Esta indagación suscitó un debate que llevó a desnaturalizar el acuerdo básico y común que había sido sostenido por los miembros de esta Comisión en una primera instancia. Si se pretendía que se reconociera la enseñanza del Holocausto como un tema de importancia para ser incorporado dentro del currículo de las escuelas, se debía considerar cuáles son los argumentos fundamentales que sostienen dicho tema. Es por ello que en este escrito proponemos dejar a un lado la cuestión del cómo llevar acabo la incorporación del Holocausto (en el que se debería trabajar rigurosamente con los contenidos de cada ciclo de la educación primaria, secundaria y superior), para dar lugar a un análisis profundo y específico de los ‘dilemas educativos a la hora de enseñar la temática del Holocausto-Shoá.Facultad de Periodismo y Comunicación Socia

Exposure to animals and risk of oligoarticular juvenile idiopathic arthritis: a multicenter case-control study

<p>Abstract</p> <p>Background</p> <p>An inverse association between early contact with microbial compounds and respiratory allergies is well established. The protective effect of infant contact with animals was also shown for inflammatory bowel disease (IBD) and systemic lupus erythematosus (SLE). We aimed to test the association between animal contact in infancy and oligoarticular juvenile idiopathic arthritis (OA JIA).</p> <p>Methods</p> <p>Parents of children with OA JIA registered at the Hospital for Pediatric Rheumatology in Garmisch-Partenkirchen were asked to complete a questionnaire. Children who underwent strabismus surgery at six referral centers for ophthalmology served as controls. Children age 6 to 18 years born in Germany without malformations were included (238 cases; response 89% and 832 controls; response 86%). Data were analyzed using logistic regression models after adjusting for potential confounders.</p> <p>Results</p> <p>Neither place of living (urban vs. rural area), living on a farm, nor regular farm animal (adjusted odds ratio 0.79; 95% confidence interval 0.42-1.47) or pet contact (0.79; 0.55-1.14) during infancy were clearly related to case status. Allergic rhinitis was inversely related to OA JIA (0.57; 0.34-0.95).</p> <p>Neither place of living (urban vs. rural area), living on a farm, nor regular farm animal (adjusted odds ratio 0.79; 95% confidence interval 0.42-1.47) or pet contact (0.79; 0.55-1.14) during infancy were related to case status. Allergic rhinitis was inversely related to OA JIA (0.57; 0.34-0.95).</p> <p>Conclusions</p> <p>Contact with farm environments in infancy might not be associated with OA JIA. This finding is consistent with previous findings for diabetes mellitus type 1 but contradicts results for IBD and SLE.</p

Polymorphisms of PTPN11 coding SHP-2 as biomarkers for ulcerative colitis susceptibility in the Japanese population.

OBJECTIVE: To identify genetic determinants of inflammatory bowel disease (IBD), we examined an association between polymorphisms of both the programmed cell death 1 gene (PDCD1) and the src homology 2 domain-containing tyrosine phosphatase 2 gene (PTPN11) and susceptibility to IBD. METHODS: Study subjects comprised 114 patients with ulcerative colitis (UC), 83 patients with Crohn\u27s disease, and 200 healthy control subjects. Five single nucleotide polymorphisms (SNPs) in PDCD1 and PTPN11 were detected by polymerase chain reaction restriction fragment length polymorphism. Subsequently, haplotypes composed of the two SNPs in PTPN11 were constructed. RESULTS: The frequencies of the Hap 1 haplotype and its homozygous Hap 1/Hap 1 diplotype of PTPN11 were significantly increased in UC patients compared to control subjects (P = 0.011 and P = 0.030, respectively). While no association was found for PDCD1 for UC or CD and none for PTPN11 for CD. CONCLUSION: PTPN11 is a genetic determinant for the pathogenesis of UC, and haplotyping of PTPN11 may be useful as a genetic biomarker to identify high-risk individuals susceptible to UC