Spin Currents Induced by Nonuniform Rashba-Type Spin-Orbit Field

We study the spin relaxation torque in nonmagnetic or ferromagnetic metals with nonuniform spin-orbit coupling within the Keldysh Green's function formalism. In non-magnet, the relaxation torque is shown to arise when the spin-orbit coupling is not uniform. In the absence of an external field, the spin current induced by the relaxation torque is proportional to the vector chirality of Rashba-type spin-orbit field (RSOF). In the presence of an external field, on the other hand, spin relaxation torque arises from the coupling of the external field and vector chirality of RSOF. Our result indicates that spin-sink or source effects are controlled by designing RSOF in junctions.Comment: 3 figure

Ferroelectric Nanotubes

We report the independent invention of ferroelectric nanotubes from groups in several countries. Devices have been made with three different materials: lead zirconate-titanate PbZr1-xTixO3 (PZT); barium titanate BaTiO3; and strontium bismuth tantalate SrBi2Ta2O9 (SBT). Several different deposition techniques have been used successfully, including misted CSD (chemical solution deposition) and pore wetting. Ferroelectric hysteresis and high optical nonlinearity have been demonstrated. The structures are analyzed via SEM, TEM, XRD, AFM (piezo-mode), and SHG. Applications to trenching in Si dynamic random access memories, ink-jet printers, and photonic devices are discussed. Ferroelectric filled pores as small as 20 nm in diameter have been studied

Fluorescence kinetics of flavin adenine dinucleotide in different microenvironments

Fluorescence kinetics of flavin adenine dinucleotide was measured in a wide time and spectral range in different media, affecting its intra- end extramolecular interactions, and analyzed by a new method based on compressed sensing

One-neutron knockout reaction of 17C on a hydrogen target at 70 MeV/nucleon

First experimental evidence of the population of the first 2- state in 16C above the neutron threshold is obtained by neutron knockout from 17C on a hydrogen target. The invariant mass method combined with in-beam gamma-ray detection is used to locate the state at 5.45(1) MeV. Comparison of its populating cross section and parallel momentum distribution with a Glauber model calculation utilizing the shell-model spectroscopic factor confirms the core-neutron removal nature of this state. Additionally, a previously known unbound state at 6.11 MeV and a new state at 6.28(2) MeV are observed. The position of the first 2- state, which belongs to a member of the lowest-lying p-sd cross shell transition, is reasonably well described by the shell-model calculation using the WBT interaction.Comment: 15 pages, 3 figure

Developmental differences in holistic interference of facial part recognition.

Research has shown that adults' recognition of a facial part can be disrupted if the part is learnt without a face context but tested in a whole face. This has been interpreted as the holistic interference effect. The present study investigated whether children of 6- and 9-10-year-olds would show a similar effect. Participants were asked to judge whether a probe part was the same as or different from a test part whereby the part was presented either in isolation or in a whole face. The results showed that while all the groups were susceptible to a holistic interference, the youngest group was most severely affected. Contrary to the view that piecemeal processing precedes holistic processing in the cognitive development, our findings demonstrate that holistic processing is already present at 6 years of age. It is the ability to inhibit the influence of holistic information on piecemeal processing that seems to require a longer period of development into at an older and adult age

Prevalence of depression in Parkinson's disease

CONTEXTO: O reconhecimento da prevalência da depressão em pacientes com doença de Parkinson (DP) é necessário para o desenvolvimento de práticas direcionadas ao tratamento da depressão e a melhora na qualidade de vida deles. OBJETIVO: Identificar na literatura indexada estudos relacionados à prevalência de depressão na DP, visto que normalmente há sub-reconhecimento e subdiagnóstico da comorbidade. MÉTODOS: Levantamento de artigos no PubMed, LILACS e SciELO que cumpriram com as palavras-chave: prevalence, depression e Parkinson. Critérios para inclusão: artigos nos idiomas inglês, português e espanhol, sem limite de tempo. Excluíram-se artigos relacionados ao tratamento da DP e validação de escalas. RESULTADOS: Selecionaram-se 20 artigos com taxas de prevalência de depressão de 1,8% a 68,1%. Seis estudos foram casos-controle, dois foram coortes, um, longitudinal prospectivo e 13, transversais. Quanto à técnica de avaliação, oito empregaram entrevista clínica, nove utilizaram apenas instrumentos de auto-avaliação, um empregou entrevista clínica e instrumentos de auto-avaliação e quatro consultaram bancos de dados. CONCLUSÕES: A prevalência de depressão variou de acordo com a metodologia, porém, em geral, as taxas foram bastante elevadas. Evidenciou-se a necessidade de definições mais precisas sobre depressão na DP para se estabelecer uma taxa de prevalência mais acurada.BACKGROUND: The recognition of depression prevalence in Parkinson's disease (PD) is necessary for the development of treatment techniques as well as the improvement in the patient's quality of life. OBJECTIVE: To identify in the literature studies related to the prevalence of depression in PD. METHODS: The search for articles was based on PubMed, LILACS and SciELO matching the key-words prevalence, depression and Parkinson. Inclusion criteria of articles were: papers in English, Portuguese and Spanish; without time limitation. Articles related to the treatment of PD and to the validation of scales were excluded. RESULTS: A total of 20 studies were selected, including six case-control studies, 3 longitudinal (2 cohort) studies, and 43 non-sectional studies. Prevalence rates ranged from 1.8% to 68.1%. Concerning the evaluation of techniques employed, eight studies used clinical interviews, nine used just self-report instruments, one utilized clinical interviews and self-report instruments and four consulted data bases. DISCUSSION: The prevalence of depression varied according to the methodology, however, in general, rates proved to be considerably elevated. The analysis reveals the necessity of more precise and consensual definitions regarding depression in PD so that more accurate prevalence rates can be obtained

Identification of distinct loci for de novo DNA methylation by DNMT3A and DNMT3B during mammalian development

De novo establishment of DNA methylation is accomplished by DNMT3A and DNMT3B. Here, we analyze de novo DNA methylation in mouse embryonic fibroblasts (2i-MEFs) derived from DNA-hypomethylated 2i/L ES cells with genetic ablation of Dnmt3a or Dnmt3b. We identify 355 and 333 uniquely unmethylated genes in Dnmt3a and Dnmt3b knockout (KO) 2i-MEFs, respectively. We find that Dnmt3a is exclusively required for de novo methylation at both TSS regions and gene bodies of Polycomb group (PcG) target developmental genes, while Dnmt3b has a dominant role on the X chromosome. Consistent with this, tissue-specific DNA methylation at PcG target genes is substantially reduced in Dnmt3a KO embryos. Finally, we find that human patients with DNMT3 mutations exhibit reduced DNA methylation at regions that are hypomethylated in Dnmt3 KO 2i-MEFs. In conclusion, here we report a set of unique de novo DNA methylation target sites for both DNMT3 enzymes during mammalian development that overlap with hypomethylated sites in human patients